Latest / Saving the World From Bad Ideas / Bad Idea #33 "Ultra Processed Foods are killing us’" with Sarah Berry

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Bad Idea #33 "Ultra Processed Foods are killing us’" with Sarah Berry · Saving the World From Bad Ideas

0:00
The term ultra processed food, we're hearing everyday, every
0:04
week there's a new headline in the paper.
0:06
Ultra processed food is linked with increased risk of this
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cancer, of Alzheimer's, of heart disease, of anxiety, of
0:13
depression, etcetera. We see something every week
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coming out that's quite scary and quite alarms.
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And alongside that we see scary figures like ultra processed
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food intake accounts for 60% of energy intake in the UK, in the
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US, in all these other countries.
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But it's really oversimplistic. It's oversimplistic because food
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is so complex and to just classify food into one category,
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ultra processed or not ultra processed, in my opinion, is
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very, very flawed. I think it comes from the
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explosion of what I call Med influencers.
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So people who have doctored before their name because they
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they might be medical professionals or or have worked
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in another area, but have never were hooked in scientific
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nutrition research. And part of it comes from this
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narrative that anything natural is obviously healthy.
1:02
We do have a problem. We do have a broken food
1:05
landscape. We are consuming too much
1:07
unhealthy processed foods. Absolutely yes, we are.
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But let's not demonise everything.
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Welcome to saving the world from bad ideas.
1:16
I'm Mark Linus and I've had a few bad ideas in my time.
1:20
I used to go out in the night time to destroy GMO crops and I
1:23
also posed nuclear power. But then when I looked at the
1:26
science I found I got it wrong. Oops.
1:28
I've learned the hard way that none of us are right all the
1:30
time. So now I'm here to challenge the
1:32
assumptions that we all too often take for granted because
1:35
the future depends on us getting it right.
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My guest today is Doctor Sarah Berry, who's a professor at
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King's College London and chief scientist at Zoe, the nutrition
1:45
health company leading the gut health revolution, as they put
1:47
it. She's an academic leader in
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nutrition science and has run more than 35 human nutrition
1:53
studies, including exploring recent topics such as menopause,
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snacking and cardio metabolic health.
1:59
She's often an expert on Zoe's own podcast, which is called Zoe
2:02
Science and Nutrition, and I highly recommend it for
2:06
everything from discussing ultra processed foods to what's the
2:09
best kind of breakfast. So, Sarah, welcome to saving the
2:11
world from bad ideas. Great.
2:12
Thanks for having me, Mark. I hope that I will be able to
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save the world today from at least one bad idea related to
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nutrition. Let's see.
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Well, I'm sure you will. And there's literally dozens,
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hundreds probably of bad ideas that people have.
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In particular, we like to bust myths.
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So let's go through a whole load of topics and see how we end up
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and whether there's a particular bad idea that you think stands
2:34
out above all of the rest of them in terms of things that
2:37
people largely believe, but actually which are completely
2:41
wrong. I did want to start start
2:42
though, just to place you a bit more and give some context to to
2:45
listeners. What is Zoe?
2:46
What's this apparently commercial company, but which
2:49
also seems to be very science based in terms of the products
2:52
it sells? Yeah.
2:53
So Zoe is a science and nutrition company and it really
2:57
evolved out of this idea eight years ago that we all respond so
3:01
differently to diet and lifestyle interventions and that
3:04
the one-size-fits-all approach, which is what population based
3:08
guidance is based on, might not be right for everyone.
3:12
So for example, we know that some people are really sensitive
3:15
to salt in terms of their blood pressure, but other people can
3:18
have their salt, eat it and not have an increase in blood
3:20
pressure. And so we designed a whole
3:24
series of quite in depth research programmes to be able
3:30
to collect data at a breadth, depth and scale.
3:32
It's never been done before. This was our PREDICT programme
3:34
of research that's still running.
3:36
We now have data on 300,000 people.
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And what this has done is enabled us to collect this
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breadth of data to tease apart what matters for whom and where.
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There are places where personalized approach would
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actually benefit someone's health.
3:51
It's very much based around gut health and around the microbiome
3:54
and our growing knowledge that the microbiome, which is that
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the trillions of species that live in our gut, actually play a
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role in terms of mediating, in part, how diet impacts our
4:05
health. And so there's this whole idea
4:07
that we can deliver personalized advice based on various metrics,
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simple metrics based on age and sex, but more complex metrics
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like that unique makeup of someone's gut microbiome as
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well. Yeah, we'll get into the
4:19
microbiome because it's actually a fairly new era of, of, of
4:23
nutrition science, isn't it? I mean, when I grew up, we just
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thought of food as something you put in and it came out on the
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other end, you know, what was left and so on.
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We didn't really think that we were in symbiosis with trillions
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of other microorganisms, which actually really, really matter
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in all sorts of ways. But before we do that, tell us
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about some of the products that you sell because, you know, I
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can't quite get beyond. There might be a bit of a
4:43
conflict of interest here between selling something
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commercially and actually running, you know, scientific
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studies which are publishing in journals.
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So how do you how do you resolve that?
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So my primary role is ASA academic at King's College
4:55
London. So that's where I run research
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groups where we have lots of independent research funding
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coming from research councils, For example, really focusing on
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how food structure impacts our health responses, which is
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particularly timely and relevant to today where 60% of the food
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that we has undergone some for to sort of processing impacts
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the food structure. I'm in a really lucky position,
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I think, to have this role at Zoe, where I lead the science
5:23
that we're doing at Zoe because despite working nutrition
5:26
sciences at a university for 25 years, I feel that very much
5:32
often we do science for the sake of science, that it doesn't
5:34
actually lead to something that ultimately provides actionable
5:39
insights and change to an individual.
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And So what I'm doing at Zowe is leading research that's trying
5:47
to unravel the complexity of who we are, how we live our lives
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and how that intersects with our diet and deliver advice to
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people through the app that we have.
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In the US, it's available as a free app at the moment.
6:00
Here in the UK it's available as a paid membership and there's
6:05
different tiers to it. So yes, it's commercial.
6:08
I've also received other commercial funding in the past
6:11
at Kings. And I do think that there is
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this idea or this narrative very much fuelled actually by this
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whole UPF argument as well by some of the some of the key
6:22
players in the discourse around UPS.
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There's this narrative that if there's funding by the industry,
6:27
it can't be trusted. Well, I think it's really
6:30
important to say there's very little independent funding
6:34
coming into universities. As academics, we spend so much
6:38
time applying for funding from research councils, for example,
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which is funded ultimately from from government.
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And if we don't work with the food industry or other
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companies, whether it be Zoe, whether it be the big food
6:52
industries like Nestle, for example, we're actually never
6:56
going to make change that actually ultimately helps
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people's health. So I do think there's the bigger
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picture here, that there's this distrust that if you're working
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with industry, obviously your science is not to be trusted.
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I don't believe that based on my own experience.
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Everything goes through very rigorous approval processes pre
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registration of clinical trials. Industry can have very limited
7:18
input on that. In terms of me having this dual
7:21
role as Zoe, I think it's actually really fortunate
7:23
because it means that I can build on my 25 years experience
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as a nutrition scientist and actually put something out there
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that will have meaningful impact.
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Yes, there's a paid product, which is our app.
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But also like you said at the beginning, we also have our
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podcast. We have lots of other
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educational materials we put out there.
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So there's lots of ways that people can benefit from all of
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this research without having to open their purse.
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You also have a supplement which is available daily, 30 I think
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it's called and apparently I'm being sent a free sample but it
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hasn't arrived yet. Just tell me any more about it.
7:58
Yeah. So about a year ago we released
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our first whole food supplement and it is called Daily 30.
8:06
It has a diversity of different plants, so 30 different plants
8:10
that then give a diversity of different fibres, which we know
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is really important. We know in nationally and
8:16
internationally people aren't getting enough fibre.
8:19
On average, only about 5% of people are actually meeting
8:22
their fibre targets. So it's quite high fibre.
8:24
But really importantly the fibre is coming in the form of whole
8:27
food and so it's coming in the form of nuts and seeds and
8:32
mushrooms, for example. We've made sure that we retain
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the what we call the matrix or the structure of the food
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because we believe this is really important.
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And again, this is based on the research that I've been doing at
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King's for the last 2025 years. And it also gives a diversity of
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lots of different bioactives. We know that food is so much
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more than a simple list of nutrients.
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We know that on average food contains about 54,000 chemicals.
8:55
And so traditionally we've thought about food in the
8:58
context of the macro nutrients, the fibre, the fat, the protein,
9:01
the carbohydrate, but actually it's all of these other
9:04
chemicals that we know play a really important role in terms
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of our health. And so by giving in, you know, a
9:10
very simple scoop each day, not only a nice fibre dose, but also
9:16
giving us diversity of different plants, we're really leveraging
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the power of these different bioactives.
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So you might have heard of words like polyphenols which have
9:25
these wonderful antioxidant like activities and act on
9:29
anti-inflammatory pathways. And so it's intended to be used
9:33
daily to be on top of your food. So for example, you could add it
9:37
to yoghurt in the morning. You could add it as a kind of
9:40
crunchy Topper to, you know, roasted vegetables or whatever.
9:43
So it's intended not to replace anything, but as a kind of added
9:48
bonus each day to your food. What we've also conducted which
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I LED is a randomised control trial to look at the
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effectiveness of the daily 30 versus a standard probiotic
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versus another kind of food Topper that you would sprinkle
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on top of your food as well. And this was a clinical trial
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that again was conducted according to good clinical
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practice, pre registered etcetera.
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And we found that it significantly improved
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microbiome composition compared to a probiotic and compared to
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the control. And it also significantly
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improved other health outcomes, but really importantly improved
10:26
how people felt, which is something that we don't measure
10:29
enough in nutrition science. So improved factors like how
10:31
well people slept, their energy levels, their mood as well.
10:35
I did want to talk a bit more about the RCTs, the randomised
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control trials, because obviously that's sort of a gold
10:40
standard in science and it's in medicine as well.
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And in medicine, of course, you have, you know, double blinded
10:45
so that neither side, the participants nor the researchers
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know when they're getting the placebo or the, you know, the
10:52
real intervention. I mean, it seems that not, not
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very much of this is done in, in, in nutrition, is it?
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And also like, how do you tell, you know, how do you actually
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get different groups when you're talking about real people?
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And it's one thing with rats where you can, you know, feed
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them, feed them like all or something like, how do you, how
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do you get real people to, to make dietary changes which can
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actually identify and avoid all of the different confounders?
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Because diets, of course, are complicated other people's
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lives. Yeah, it's really, really hard
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running randomised controlled trials.
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Designing randomised controlled trial protocols are set with
11:27
many challenges. It's not as simple as a drug
11:29
trial. You can't have a placebo in many
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cases. So there's lots of different
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factors that we need to consider.
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Firstly is how much can we blind it?
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So it might be that we're looking at a very simple
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ingredient. So I do lots of work looking at
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dietary fat, so looking at seed oils for example, and so I could
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compare that to butter by incorporating it into a food.
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So I've done lots of trials where I might feed people
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different spreads, different breads, different cakes, for
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example, where on some occasions they're having it with the seed
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oils in and on other occasions they're having with the butter.
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In that case, there is an element of blinding.
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But even when you can blind it in that way, you then have the
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challenge of, well, hold on, what else is changing in their
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diet? And so whenever you add
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something kin as part of a nutrition trial, often you're
12:19
replacing something else. And that's why you've got to be
12:21
really, really mindful about what it is that you're
12:24
replacing, how you're introducing that that food or
12:27
that nutrient or that ingredient into the diet.
12:31
And so that's a real skill and something that I've spent a lot
12:35
of time perfecting over the years is these kind of dietary
12:38
interventions. I've now run 35 randomised
12:40
control trials. And it's the hardest part of the
12:43
trial is how am I going to make that dietary modification and be
12:48
able to be sure that the outcome that I'm seeing that's changing
12:51
is due to that dietary modification rather than
12:53
something else has changed. And you actually care, right?
12:56
Because you're not just doing this for marketing purposes.
12:58
You actually do want it to work in almost like a medical way,
13:01
right. So because I'm imagine a lot of
13:04
what's on on the packets of things, you know, probiotic good
13:06
for gut health, whatever. I mean, it's not, it's not like
13:08
that's tested in gold standard RCTs is.
13:10
It absolutely that the Biome study that we did to test the
13:14
daily 30 was tested in a randomised control trial and all
13:19
of the other trials that I've conducted at King's have been to
13:23
answer hypothesis, have been to answer a question.
13:26
Are seed ores better than butter?
13:28
For us, most of the time this funding has come from
13:32
independent funding bodies like research councils.
13:35
So we have the BBSRC for example, or they might come from
13:38
charities, sometimes they come from organisations.
13:41
But it's driven by a desire to answer a really important
13:45
question related to how diet impacts our health.
13:48
It's as an academic, we're not there to drive sales to any
13:51
products. We're there to understand
13:53
underpinning mechanisms, how we can improve the food landscape,
13:56
what changes we can make to improve people's health.
14:01
And yes, it's really challenging.
14:02
The other big challenge that you alluded to as well is who do we
14:06
recruit? And again, that's really, really
14:08
important when you're thinking about running a clinical trial
14:11
related to diet. Who you recruit is is one of the
14:15
most important factors as well. Are you going to recruit males
14:18
or females? Are you going to recruit people
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that are slightly metabolically unhealthy so you've got a better
14:23
chance of detecting a difference?
14:26
What's your main outcome? If you're interested in blood
14:28
pressure, do you want to recruit people that have slightly
14:30
elevated blood pressure or do you want people with normal
14:32
blood pressure? How will you recruit enough
14:35
people that are representative of the population?
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And this is really challenging because research funding is very
14:42
limited. You cannot run a very tightly
14:45
controlled dietary study in thousands of people.
14:48
It's just not possible. Well, not possible within the
14:51
kind of funding that most people get.
14:54
And so quite often we have to make very hard decisions about,
14:59
OK, are we going to recruit a population group that we know
15:03
that we're likely to see a difference so that we can show
15:05
proof of principle. And then after that we can go
15:08
and look at the wider population, how it actually
15:11
plays out. And so we work very hard at
15:14
deciding who we're going to recruit, but also how we're
15:17
going to recruit. And it's one of the really soul
15:19
destroying parts of research often is trying to recruit
15:22
people, trying to recruit that right demographic and also
15:25
trying to keep them motivated to make the dietary change or eat
15:29
the food or ingredient that you've asked them to consume for
15:32
whatever period of time. So RCT said one thing, what
15:35
about how, how else do you see measure scientifically trends or
15:39
relationships between diet and health?
15:41
I mean in in the wider population and and do that in a
15:44
rigorous way. So our gold standard is the
15:46
randomized controlled trials. There's also other ways that we
15:49
can monitor people. So we call these epidemiological
15:54
or population based studies. So we can very simply just look
15:57
at a point in time at a large proportion of the population and
16:01
say, OK, what are they eating? What is their health outcomes or
16:06
their blood pressure or their cholesterol levels that gives us
16:10
a first indication or a first hint that there's some sort of
16:13
relationship there. We can also do epidemiological
16:17
style studies or we call these often population style studies
16:20
as well. And this is enables us really to
16:23
get a first hint that there's something going on.
16:26
And So what we can do at the kind of lowest level is look
16:28
what we call cross sectionally. So we can look at a given point
16:31
in time at a rate of a disease and a certain exposure.
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So in my case, it'll be looking at a dietary exposure.
16:38
So I might be interested in looking at how much seed oils
16:42
people are eating or how much butter they're eating and what's
16:45
their cholesterol levels or what's their rates of heart
16:47
disease. Now that gives us an indication
16:50
if there's a relationship. The problem is, is that there's
16:53
loads of other things that are going on at the same time.
16:56
Yes, we can use statistical approaches to try and somewhat
16:59
account for that, but you can't fully account for everything
17:02
else that might be going on at the same time.
17:06
And what we can do is what we call longitudinal studies.
17:09
And these are studies that where we follow people over a period
17:12
of time. And there's big cohorts out
17:14
there. So you may have heard of some of
17:16
the Harvard cohorts, like the Nurses Health study, for
17:19
example. And these are studies where we
17:21
follow people over a number of years and at regular time points
17:25
we ask some questions. We might do measurements of
17:27
things like blood pressure, cholesterol, you know, and other
17:30
kind of biospecimens that tell us lots about their health.
17:34
And by monitoring them longitudinally over that period
17:37
of time enables us to go to the next step where it's not just
17:41
this clue of an association, but that actually there is something
17:46
going on a bit more here that actually as we see people's
17:49
levels of seed oil increase, for example, we're seeing a lowering
17:54
in those people of their cholesterol.
17:56
Yet as people over 1020 years are having more butter, those
17:59
people are tending to have an increase in cholesterol.
18:02
Again, there's lots of other confounders.
18:04
What else is changing in that 20 years?
18:06
Not only their age, not only their body weight, potentially
18:09
there could be loads of other things that they're exposed to.
18:12
And so that's why we try and go to that final level of
18:14
randomized control trials where we have an idea there's
18:18
something happening here. Again, let's use butter and seed
18:22
oils as an example that hey, there's something going on where
18:25
seed oils might be protected, butter might be unhealthy for
18:28
us. Let's test this in a randomized
18:30
control trial. Let's recruit a proportion of
18:34
people. Let's get them to consume for
18:37
certain period of time, a diet high in butter, for another
18:40
period of time, a diet high in seed oils.
18:42
Let's take measurements pre and post.
18:44
We've exposed them to these different interventions.
18:47
And let's look what's changing, and also let's look at the
18:49
mechanisms, because that's really important as well, not
18:52
just to see the change, but to understand if there's a
18:54
plausible underlying mechanism as well.
18:57
Thank you for that, that details and very useful explanation.
18:59
I think people will be interested actually about what
19:01
you've found, particularly with butter and seed oils.
19:04
I remember this there being some kind of controversy about seed
19:06
oils, particularly in the US where the, the crazy clowns at
19:10
Maha, you know, Robert Kennedy Junior and all of those anti vax
19:14
lunatics were trying to get, you know, McDonald's switched back
19:18
to beef tallow or something like that because they said that
19:20
vegetable oil was poisonous. I mean, what does the science
19:22
say that you you found on seed oils versus animal fats?
19:25
So I'd love to summarise the totality of the evidence and I
19:28
think this is really, really important because one thing that
19:31
we haven't touched on is the final kind of icing on the cake,
19:34
so to say, above. Randomised control trials are
19:37
what are called meta analysis, where you can look at all of the
19:41
different randomised control trials that are out there.
19:44
So I would be remiss to only talk about what my studies have
19:47
found, given that my study might find something different to
19:51
other studies if I studied a very specific population or a
19:54
very specific type of seed oil. I also probably need a bodyguard
19:58
after talking about this. The last time I spoke out about
20:01
seed oils, I got 4000 hate messages.
20:05
And I even got an e-mail from someone asking how does it feel
20:08
to be the most hated scientist in America right now?
20:11
Because I dared to question the narrative that Sea Doors are
20:14
toxic because the totality of the evidence very clearly shows
20:18
that they're not toxic. Wow.
20:19
And producer Rob told me about this, that you were on some big
20:21
podcast in the US. Just give us give us the the
20:25
details of that because I think it's fascinating.
20:27
So I went on to the Diary of a CEO Stephen Butler podcast and
20:31
we did some myth busting. And I love myth busting testing
20:35
around seed oils. Partly because I've researched
20:37
in this area, partly because there is a wealth of
20:40
misinformation unfortunately around seed oils and having
20:44
broken down all of the arguments as to what the seed oils, the
20:48
toxic people say versus what the evidence shows, there was a
20:52
massive backlash and I was inundated with quite mean
20:58
comments. I was called an industry shill.
21:01
And for the record, I've actually never taken a penny
21:03
from the seed oil industry or the fats and oils industry I was
21:07
asked for. What do I know?
21:09
Because they've read a book by some ex TV star who has written
21:13
all about how seed oils are toxic.
21:15
But my 25 years in nutrition sciences, irrelevant.
21:19
And yeah, I got lots of hate emails to swell around this.
21:23
But what it's done is it's actually motivated me to speak
21:26
out more about the misinformation because there is
21:28
so much misinformation, not just on seed oils, but lots of other
21:31
areas as well. Maybe that's a good candidate
21:33
for our bad idea that you're that you're busting.
21:35
But I wonder whether where the narrative comes from.
21:38
Do you think it's naturalistic fallacy that animal fats are
21:41
something our grandparents ate and it's all fine, whereas seed
21:43
oils are sort of processed and, you know, refined from modern
21:46
agriculture? I mean, there's always a
21:48
narrative which underpins why people are much more likely to
21:51
believe a certain thing, isn't there?
21:53
Yeah. So I think it comes from a
21:54
number of areas. I think it comes from the
21:57
explosion of what I call Med influencers.
22:00
So people who have doctor before their name because they they
22:03
might be medical professionals or or have worked in another
22:06
area, but have never were hooked in scientific nutrition
22:09
research. And part of it comes from this
22:12
narrative that anything natural is obviously healthy.
22:16
And this narrative that butter with the cows grazing in these
22:19
beautiful fields with butter cups is natural for us.
22:23
And yet seed oils have gone through this terrible processing
22:27
by the food industry, are evil and out there to kill us.
22:30
And you know, you see terms like bleaching and deodorisation,
22:34
etcetera, which are processes used in order to refine, clean
22:40
and make stable the seed oils, but that they do not do any harm
22:45
to our health. So that's one of the the
22:47
narratives that are is out there.
22:50
There's also the narrative that seed oils are inflammatory.
22:54
So seed oils contain a particular fatty acid in them,
22:58
which is called linoleic acid. It's called also known as an
23:01
Omega 6 fatty acid. So it's a polyunsaturated fatty
23:04
acid and what we know is if you look at the theoretical
23:08
biochemical pathway, this particular fatty acid can be
23:12
converted to another one which is called arachadonic acid.
23:15
Sorry to get technical but it's quite important here.
23:18
And upon certain stimuli, arachadonic acid can release
23:22
mediators that act on pro inflammatory pathways.
23:26
So when you look at it written down on paper, it's then quite
23:29
plausible that you increase your intake of seed doors, therefore
23:32
you increase your intake of this Omega 6 polyunsaturated fat
23:36
called linoleic acid. And while you're going to
23:38
suddenly get more of this other fatty acid and all of these
23:41
inflammatory mediators that can happen in a Petri dish, it can
23:46
happen in a mouse at super physiological doses under
23:50
certain stimuli. It does not happen in humans.
23:54
There are meta analysis and remember, these analysis have
23:56
many randomized control trials. There are meta analysis of more
23:59
than 35 randomized control trials looking at either seed
24:04
oils or this particular polyunsaturated fatty acids that
24:07
show that when fed to humans, they do not increase circulating
24:10
inflammatory markers. They are not inflammatory.
24:13
But it's all very well to put on your Instagram page a picture of
24:17
this bare chested man in a supermarket munching away at
24:21
this, you know, big bit of butter or, and then show this
24:25
like scary biochemical pathway with all of these inflammatory
24:29
mediators. Yes, fine, it's a correct
24:32
pathway. But it does not happen in
24:33
humans. And the totality of the evidence
24:36
consistently shows people who consume more seed oils are
24:40
healthier. They have lower cases of all
24:42
'cause mortality, meaning death, they have lower rates of
24:45
cardiovascular disease and so forth.
24:48
But again, it's this narrative as well around food processing
24:52
being evil. And again, these kind of scary
24:55
terms are put out there. The other big problem that we
24:57
have, and this takes us back to what we were talking about
25:00
around scientific evidence and different types of scientific
25:03
evidence. You often see these beautiful
25:07
figures where you see this line chart showing that as our intake
25:13
of Sea Doors has increased, so is our our rates of all of these
25:16
scary diseases, cardiovascular disease, type 2 diabetes,
25:19
obesity, cancer and so forth. And they showed that over the
25:23
last 50 years, look, seed oils have increased So has all of
25:26
these scary diseases. Yes, that's correct.
25:29
But what else has changed in those last 50 years?
25:33
You know, our food landscape is beyond recognition.
25:35
Plus about 60% of the seed oils that we consume are in these
25:40
heavily processed unhealthy foods that have got loads of
25:43
other nasties in that it's not the seed oils themselves that's
25:46
the problem. And so it's, it's a great
25:49
example, I think, and I often use this for the students I
25:52
teach at King's to show how on social media you can present a
25:56
very plausible argument around the food and nutrient and
26:00
ingredient and its relationship with health, which is actually
26:04
totally and utterly wrong if you take that little bit deeper dive
26:08
into the evidence. Absolutely.
26:10
And you've mentioned Processing and Ultra processing a few times
26:12
and having watched a few Zoe podcasts, there's a lot of talk
26:16
about processing as if it's always don't mean to be
26:20
oversimplifying, but as if it seems it's a bad thing, right?
26:23
You ultra processed foods are bad.
26:25
Now, that's clearly has to be simplistic.
26:27
It can't, that can't be true in and of itself.
26:30
But how do you navigate this whole conversation and debate
26:33
about ultra processed foods and tell us where the concept
26:36
originated from and how they're generally classified?
26:39
Yeah, So this is a big topic and the term ultra processed food,
26:45
we're hearing every day, every week there's a new headline in
26:48
the paper. Ultra processed food is linked
26:50
with increased risk of this cancer, of Alzheimer's, of heart
26:55
disease, of anxiety, of depression, etcetera.
26:58
We see something every week coming out that's quite scary
27:01
and quite alarmist. And alongside that we see scary
27:04
figures like ultra processed food intake accounts for 60% of
27:08
energy intake in the UK, in the US, in all these other
27:11
countries. But it's really oversimplistic.
27:14
It's oversimplistic because food is so complex and to just
27:17
classify food into one category, ultra processed or not ultra
27:22
processed, in my opinion, is very, very flawed.
27:25
Now the term ultra processed came out from a classification
27:29
system that was created in Brazil.
27:31
It's called the Nova classification system and it
27:34
categorises food into four categories.
27:37
So you've got your your unprocessed, your processed
27:41
culinary ingredients, and then you've got this worst category
27:44
which is called Nova 4, which is your ultra processed food.
27:47
We call it UPF for short and this classification is based on
27:53
the extent and the purpose of processing.
27:56
And so if it falls into Nova 4 or if it's classed as UPF Ultra
28:00
processed food, it is decided upon based on how much it's
28:04
processed and the purpose of that processing.
28:08
It was never designed to look at how the processing itself
28:12
impacts our health. And that's the biggest flaw to
28:14
this. And it's so over simplistic and
28:17
it's really difficult to know what is that food ultra
28:19
processed, isn't it? And not all ultra processed food
28:22
is bad for us. And I think this whole narrative
28:25
that 60% of our energy is coming from ultra processed food I
28:29
think is really unhelpful. And I think it's unhelpful for a
28:31
number of reasons. Firstly, because we know that
28:34
food processing serves a really important function.
28:37
It makes the food the shelf stable.
28:40
It makes it safe to eat. It also can significantly reduce
28:46
the cost of food. So analysis has shown that a
28:49
processed version versus a least processed version of a food
28:53
within a food group. So let's take breads for
28:55
example. There is on average 50%
28:58
difference in the price. So if you take a heavily
29:01
processed yoghurt versus a minimally processed yoghurt, on
29:04
average, the heavily processed will be 50% cheaper.
29:08
And so we also need to make sure that when we talk about auto
29:11
processed food, we're not demonising it all in such a way
29:15
that, you know, for those people who can only afford the
29:18
processed version, we're therefore creating more of a
29:22
disparity in health as well. And I think the biggest problem
29:27
is, is that not all processing is bad for us.
29:30
And I think this is where the term UPF is really unhelpful.
29:34
So you could have, for example, peanut butter and you could have
29:38
three different types of peanut butter.
29:39
You could have a minimally processed, so in the UK,
29:43
something like pip and nut, which is basically ground
29:46
peanuts. And then you've got a little bit
29:47
of salt. You could have something that's
29:50
in there kind of middle ground like a sun pat peanut butter
29:53
that we have here in the UK that's got a few emulsifiers and
29:56
a couple of other things in it still, I think quite reasonably
29:59
healthy to have. Then you could have on the other
30:02
extreme, something like the Reese's peanut butter that you
30:04
can get here in the UK and the US and many other countries that
30:08
if you look at the list of ingredients, it's excessive.
30:10
There's so many ingredients, additives, emulsifiers, it
30:13
doesn't resemble the food it's it's come from at all.
30:17
Now that's some part, the one in the middle and the Reese's would
30:20
both be classed as ultra process because they happen to both have
30:23
some sort of additive in, but their health effects are hugely
30:27
different. And the reason I wanted to use
30:29
this as an example is because much of the evidence that's out
30:32
there that we see these scary headlines saying ultra processed
30:36
food are killing us, accounting for all of these deaths are
30:39
based on evidence that uses very crude dietary assessment tools.
30:46
So typically in nutrition research, what we will use when
30:49
we're doing these big population studies is food frequency
30:52
questionnaires. So we might ask someone as part
30:55
of those food frequency questionnaires, do you consume
30:58
nut butter? That's about as detailed as it
31:01
would ever get. That's not going to tell us.
31:03
Is it the Pippa nut that's really healthy for us, or the
31:06
recess that's really unhealthy. It might ask, do you consume
31:09
bread again? You could have this really
31:12
healthy rye bread or you could have a terribly unhealthy white
31:14
bread. And so a lot of the evidence
31:18
that's out there, when you actually break it down to food
31:20
groups, we actually see that it's mainly food groups like
31:25
sugar sweetened beverages or processed red meat that's
31:28
driving a lot of this association.
31:31
And so we need to therefore take some of these scary headlines
31:34
with a bit of caution. However, Mark, I do think it's
31:37
really important to caveat that we do have a problem.
31:40
We do have a broken food landscape.
31:41
We are consuming too much unhealthy processed foods.
31:45
Absolutely, yes, we are. But let's not demonize
31:48
everything. And I think the way to stop
31:51
demonizing everything because by understanding what it is about
31:55
food processing that makes the food less healthy or more
31:58
healthy. And that's what I've spent much
32:00
of my 25 years looking at, looking at dietary fats and seed
32:04
oils, but also looking how processing can impact the
32:08
helpfulness of the food. Fascinating.
32:10
Probably the removal of most of the fibre as well in most ultra
32:13
processed foods. I wanted to ask particularly
32:15
about, you know, vegetarian and vegan alternatives to so-called,
32:18
you know, natural meat as in defined as edible parts of an
32:22
animal according to the latest EU thing where they're trying to
32:24
ban the use of burger and sausage on alternative plant
32:27
based packaging. And of course, they also get
32:30
demonized in particular by the meat industry for being ultra
32:34
processed. And it's the most obvious thing
32:36
to slap on them. You see a lot of this in the US
32:39
now in terms of the pushback against alternative proteins.
32:42
And you know, and of course, I'm going to ask you whether you
32:45
agree on this. You know, we need to move people
32:47
away from having such meat, meat heavy diets towards more plants,
32:51
plant based alternatives. And of course, that's
32:53
environmentally crucial to free up large areas of land for
32:56
rewilding and ecological restoration, which is currently
32:59
used to feed livestock. So what's your what's your take
33:02
on on that whole issue? So I think putting aside animal
33:06
welfare and the environmental side of things and thinking from
33:10
a health perspective, I think again, it's quite new and I
33:13
think that meat alternatives are a fantastic option for people
33:17
who have been reliant on meat and would struggle, struggle to
33:21
transition straight to a vegetarian diet.
33:24
And so I think it's a great stepping stone for many
33:26
individuals. And there's been some nice
33:29
research showing that by having that as a stepping stone enables
33:32
people to reduce their meat intake and transition more to a
33:35
vegetarian diet. So I think that's one element,
33:37
the behavioural side of things, because we have to remember that
33:40
what we eat is so much part of our upbringing, our culture, you
33:45
know, our social setting. It's really difficult to change
33:48
that behaviour. And if you've been brought up
33:50
where you're kind of that two veg, potatoes and meat kind of
33:54
household, just changing overnight to beans is not going
33:57
to happen. So I think for that kind of
33:59
setting, it's a fantastic option.
34:02
The meat alternatives is such a huge area in terms of they are
34:08
so, so different. So one meat alternative burger
34:13
versus another meat alternative burger could be hugely
34:16
different. You have ones that are based
34:18
more, for example, on mushrooms, so kind of fungal fungi, for
34:23
example. You have other ones that might
34:26
have some soya protein and might just be full of terrible things
34:31
or, you know, in them. So I think it's very difficult
34:34
to say. OK, absolutely.
34:36
Meat alternatives are better or worse than meat itself because
34:39
it depends on the type of meat alternative.
34:41
On average, meat alternatives do tend to be quite slightly higher
34:44
in salt, but they tend to be slightly lower in saturated fat.
34:48
But it's so dependent on the individual meat alternatives in
34:53
terms of health outcomes. But we do have a problem that we
34:56
cannot continue to feed our growing nation in the way that
35:00
we currently eat if we continue to be reliant on meat.
35:04
And so I think it's a great stepping stone in the right
35:06
direction. Yes, if we can make them in a
35:09
way that preserves either the original food matrix or that
35:14
ensures that they don't have too many additives and multifiers or
35:18
or too many any too much salt, for example in them, then you
35:22
know, obviously that's going to be better for us.
35:24
Yeah, I ask also because, you know, there's a lot of debate
35:30
about whether vegan diets are, you know, fully healthy or not.
35:34
I see it, Zoe, you you promote cheese and full fat yogurts and
35:38
oily fish and things like that. I mean, that sort of tends to
35:41
the conclusion that actually you can't get all of these nutrients
35:44
from a, from a fully vegan diet. So what's your what's, what's
35:47
the sort of what's the science say on that?
35:49
So this isn't my area of expertise of vegan diets.
35:52
I can give you kind of my top line opinion having worked in
35:55
nutrition science for so long. So if planned appropriately, I
35:59
believe you can get all of the nutrients you need from a vegan
36:03
diet. But the the nuance here is that
36:06
if planned appropriately, so I believe to get preformed very
36:11
long chain omega-3 fats that you would get typically an oily fish
36:14
is really important. Your body can convert some of
36:17
the shorter chain versions. People often talk about a fat
36:20
called alpha linolenic acid that's in flaxseed, for example,
36:24
but you convert that at very limited rates.
36:26
So this is an example where actually if you can get the
36:29
preformed version, which you can get from fish, then you know,
36:33
that's a real advantage to not having a vegan diet.
36:36
But this is where the if planned appropriately.
36:39
There are algal supplements that have that preformed version, but
36:42
they're expensive. They're not accessible to
36:44
everyone. And so I do think it's quite
36:46
difficult sometimes because I think there's a lot more thought
36:49
that needs to go into it and there might be an added cost.
36:53
There is a current obsession with protein and there's a
36:55
current obsession particularly in the US about protein and
36:58
getting your protein from animal based foods.
37:01
We know that protein from animal based foods is what we call a
37:05
complete protein. It contains all the essential
37:07
amino acids that you need. We know in plant based foods, so
37:11
pulse of seeds, for example, we know that yes, they do contain
37:15
protein, but they don't contain the amino acids in the same
37:20
ratio that they are there is in meat.
37:23
And so again, this is where you just need to make sure you're
37:25
planning a bit better. You can get all of your protein
37:28
needs. You can get all of your
37:29
essential amino acids. You can get the right amount of
37:31
essential amino acids from plant based foods as long as you're
37:34
getting a diversity. So you need to make sure you're
37:37
having whole grain sources of protein, nut sources of protein,
37:42
pulses and bean sources of proteins.
37:44
If you're mixing those different sources then you will still get
37:47
all the nutrients that you need from a plant based diet in my
37:50
opinion. Maybe that's another bad idea.
37:52
We need more protein because protein is, as you say, it's,
37:55
it's like it is the big obsession, isn't it?
37:57
And it's not just for people who are going to the gym and for
37:59
young guys who are trying to bulk up.
38:01
I mean you see protein on everything now, however
38:04
unhealthy in order to. Well, I guess there's a
38:07
marketing scam. So two things that shock me when
38:10
I go to the states that I think are a bad idea are restaurants
38:15
that now have signs outside saying seed or free because
38:19
there is this obsession with seed oils.
38:21
And when you go into the restaurant, you have different
38:25
areas. And there is an area, if it's
38:27
like a sandwich bar star restaurant for your protein
38:30
source, high in protein, you go to the supermarket high protein
38:34
bars. Now, yes, we need protein just
38:36
like we need fat in our diet. But actually, nearly all of us
38:40
get enough protein. Very few people are deficient in
38:44
protein. Just following a normal diet
38:46
means that we get enough protein, most of us actually
38:48
getting more protein than we need.
38:50
Not that there's a. Even if you're going to the gym
38:52
and even if you want to bulk up. So if you're going to the gym,
38:56
you want to bulk out. If you're post menopausal
38:58
slightly older people, yes, you need slightly more protein, but
39:02
not to the extent that some of these influencers are saying, in
39:06
my opinion. And whilst there isn't a risk of
39:10
going moderately high protein to your health, there is a real
39:13
risk that by adding that protein into your diet, you're
39:16
displacing something you need more.
39:18
And that's what we've always got to think about when you add
39:21
something in, what are you taking away?
39:23
And a lot of protein sources, unless you're getting them from
39:27
the nuts, the seeds that the pulses and whole grains, a lot
39:31
of protein sources come from sources that are very low in
39:35
fibre. What are we deficient in?
39:37
In most countries, fibre. So only 5% of people are meeting
39:40
fibre requirements. This is what we need to be
39:43
doing. So another bad idea is that
39:46
we're not focusing on fibre enough.
39:48
If we could increase our fibre intake, we would significantly
39:51
reduce our risk of many chronic diseases, from cancer to
39:55
cardiovascular disease and so much more.
39:57
I mean, fibre doesn't taste like taste nice like a steak to us or
40:01
have the mouth thrill of fast, does it?
40:02
So like, how do we how do we answer that question?
40:06
That's a really good point and it's something that I'm working
40:09
on with my kids to make sure they increase their fibre and
40:12
find it tasty. There are lots of fibre sources
40:15
that can be tasty. So nuts, seeds, pulses that I
40:19
I've mentioned, but just incorporating them into your
40:22
everyday foods. My kids love spaghetti
40:24
Bolognese. I sneak in pulses that I just
40:27
blend up and put it in so that it's snuck in some extra.
40:30
A few lentils or something, right?
40:32
A few. Like some lentils, Yeah.
40:34
Just like lentils. Sneaking those in, for example.
40:37
There's lots of ways that you can sneak things in.
40:39
But, you know, just encouraging our kids to eat food, eat
40:42
vegetables, you know, going back to the basics.
40:46
Yeah, I made some whole wheat spaghetti yesterday and it just
40:50
isn't as nice. It has this kind of bitter taste
40:52
to it. And I saw that and you know, I'd
40:54
take your point about fibre, but it is, it is just probably one
40:57
of the hardest things. Listen, I want to talk about the
40:59
microbiome because I know that's a real central part of the work
41:02
that you're doing. I'm not sure how first how how
41:05
to get get to this, but like it didn't used to be a thing.
41:09
For how long has it been a thing?
41:10
And how did it become such a big thing?
41:13
So I would say microbiome became a thing in the last 10 years or
41:17
or so. There are many new areas of
41:20
nutrition that have become a thing in the last 30 years.
41:23
So 30 years ago, we were very much at a point in time where we
41:27
thought that our responses to diet, lifestyle, everything was
41:31
in our genes, that we were predestined to be as we are due
41:35
to our genes. We actually know now that only
41:37
about 20% of how we evolve in terms of our health is due to
41:42
our genes. So our risk of cancer,
41:45
cardiovascular disease and so forth, most of that is only
41:48
accounted about 20% due to genes, which is really
41:51
empowering. I'm a child brought up in the
41:53
70s where I was told, well, it's all down to your genetics.
41:56
Actually it's not. It is largely under our control.
41:59
So 80% on average. Obviously it's different for
42:02
different people. Some people might have a very
42:04
particular unusual genetic, you know, make up.
42:08
But for most of us, 80% of us in terms of our disease risk, in
42:13
terms of, you know, how we will go on to age develop is down to
42:16
modifiable factors. And these modifiable factors are
42:20
our diet and our lifestyle and how they impact our body we now
42:24
starting to understand is partly mediated through the microbiome.
42:29
And this is an area that I think, you know, has exploded,
42:33
particularly in the last 10 years.
42:35
We still are learning so much more.
42:37
So the microbomes are trillions of bacteria that live in our
42:41
gut. And what we know is that the
42:43
bacteria can impact how a food impacts our health.
42:49
And so it's an area that we're focusing on a lot as Zoe.
42:54
So we know that there are certain species that are
42:57
associated with certain health outcomes.
43:00
We know that some people might have certain species that are
43:03
linked with low blood cholesterol or.
43:06
These these are species of microbial organisms living in
43:09
the gut, right? Yes, yes, correct.
43:12
Because I've seen, I've seen you market something called the Zoe
43:15
gut shot. And I thought, how does this,
43:19
how does this presume it's got live microorganisms in it?
43:22
Like how does it get through the stomach without being fried by
43:24
stomach acid? Yes, that's a really good
43:26
question because what we know is that when you consume what's
43:30
called a probiotic, which is live bacteria, a lot of it is
43:33
destroyed. But there's this whole area
43:35
called post biotics, which is like the dead material that
43:39
these bacteria produce seems to also have of an impact in terms
43:43
of our health. And so we can see this from
43:46
evidence from supplement trials. So this is where people are
43:50
given either a placebo or particular probiotic in a
43:52
capsule form, where you then see a change in their gut microbiome
43:56
and also a change in certain health outcomes.
43:59
Tell us a bit more about how the gut works and how the microbiome
44:02
actually effects overall body functioning, right?
44:05
Because I even my dad has Parkinson's and I think I read
44:08
somewhere that dopamine is actually produced in the
44:10
microbiome. So there may even be a link with
44:11
the microbiome and some of these some of these chronic diseases
44:14
too. There's so much we don't know
44:16
about the gut microbiome because we're only just really
44:18
understanding how important it is.
44:20
We know that the gut microbiome can produce certain chemicals,
44:24
and it can produce chemicals locally that acts locally in the
44:28
gut, but chemicals that also can have effects everywhere else in
44:32
our body. We know that food modulates
44:34
partly what chemicals the microbiome might produce, and we
44:38
know that many of these chemicals dependent on the type
44:42
of bacteria there, can have favourable impacts.
44:44
So one of the most important chemicals that these bacteria
44:48
produce is something called short chain fatty acids.
44:50
And short chain fatty acids can have a really important effect
44:53
in terms of maintaining the helpfulness of our guts.
44:57
So they're very protective against, for example, colorectal
45:00
cancer. They might also act on
45:02
inflammatory pathways in a beneficial way and so forth.
45:06
It's actually really complicated how the bacteria act in terms of
45:12
diet. And I think a really nice
45:14
example I could give you is related to menopause, because
45:17
this is something we have done some research on.
45:19
So what we know is that if you supplement people with soy
45:23
isoflavones, and so this is a particular chemical that's found
45:27
in soy that acts like an estrogen chemical.
45:31
So they're also called phytoestrogens.
45:34
When you supplement someone with soy isoflavones, what happens
45:38
is, is the soy isoflavones bind to the estrogen receptor and
45:42
they can reduce your menopausal symptoms.
45:45
But we know that it's really variable between individuals.
45:48
And we now know that some people contain particular bacterial
45:52
species in their microbiome that can convert the soy isoflavones
45:57
to a really active form that binds really tightly to the
46:02
estrogen receptors. And what it does is it produces
46:06
this particular chemical called equal that binds really tightly.
46:10
And so people that have these species that are able to convert
46:14
soy isoflavones into this really active form called equal, have a
46:19
75% greater reduction in menopause symptoms when they're
46:23
supplemented with soy isoflavones versus someone that
46:26
doesn't have that particular species.
46:29
And so I think that's a really great example of the power of
46:31
the microbiome, but also to show how variable our responses are.
46:35
So just because my friend who's perimenopausal might say, wow, I
46:38
have this new isoflavone supplement and look, my symptoms
46:41
have gone. They might have that species
46:44
that enables them to create this particular potent chemical.
46:48
And yet I might try the same supplement, have no improvement
46:51
in my menopausal symptoms. And it's down to our gut
46:54
microbiome. And we're starting to see this
46:56
in so many different areas now. And I think that's what's quite
47:01
exciting. I would say not everything is
47:03
due to our microbiome because I know that, you know, we do have
47:07
to be mindful that food, diet, lifestyle, you know, acts in
47:12
ways that it's also independent to our microbiome.
47:15
But it seems to be playing quite a fundamental role, which I
47:18
think is exciting. And I think the future holds a
47:21
lot of potential here. And how do you measure your
47:23
microbiome? Does it mean a poo sample?
47:26
It means a poo sample and you can measure it lots of different
47:29
ways. At Zoe You, we use something
47:32
called metagenomic sequencing and this is conducted by a
47:35
professor who heads up a big team in Italy at Trento
47:38
University who undertakes this. How it's done, the readouts they
47:42
get blow my mind. It's beyond my Gray matter to
47:46
fully understand it, which is why you need people who have
47:49
expertise just in that area to then interpret it.
47:53
I also wanted to ask about organic foods, which were a big
47:55
thing maybe 10 or 15 years ago and I think have receded
47:59
somewhat. But obviously, the environmental
48:00
movement was always busily promoting organic.
48:03
And the supposed reason for this was, you know, that they weren't
48:07
using artificial pesticides, and obviously that meant that
48:10
they're getting lower yields. And, you know, there's all
48:12
sorts. I don't want to get into the
48:13
whole organic versus conventional debate, but in
48:16
terms of diet, was there ever any evidence that organic foods
48:19
were better for you in terms of dietary health?
48:21
So this is another that isn't my main expertise, top line.
48:26
And I'm sorry Mark, I know I'm quite often saying it's not my
48:28
expertise, but I think any good scientists will put their hands
48:32
up to say when it's not something that an active
48:35
researcher in my top line view on organic is that it doesn't
48:40
mean it's healthier for you, that yes, it might have lower
48:43
levels of pesticides. So for example, if you take
48:47
oats, organic oats will have lower levels of glyphosates, but
48:51
the level of glyphosates in non organic oats is still very low.
48:55
And unless you're having kilos and kilos of oats every day, I
48:59
don't think it's enough to warrant any concern.
49:02
I think in terms of the nutrient profile, there's very limited
49:06
evidence to show that organic or non organic it is different or
49:11
one is superior than the other. In some instances non organic
49:15
might be superior because of preservation of certain parts of
49:20
plant for example. In other instances organic might
49:22
be better. So I would say the juries do out
49:25
in terms of what is better health wise nutritionally
49:28
between the two. If you are worried about
49:30
pesticides then yes the levels will will be lower, but I
49:33
believe that the levels within most foods are not are of
49:39
concern. Thank you.
49:40
And every time you caveat your response by saying it's not your
49:43
over expertise, you, you, you rise in my level of scientific
49:46
credibility because that's, that's exactly the sort of thing
49:49
you should say if you're a proper science scientist.
49:51
So thank, thank you for that. It doesn't it doesn't detract at
49:54
all. I'd quite like to go back just
49:56
to how science works on this because I think there's one, one
50:00
of the other myths is that they keep changing their minds.
50:03
Like, first margarine was good for us, then it was butter.
50:05
And, you know, coffee was, you know, stopped cancer and now
50:09
coffee gives you cancer. Or or was it the reverse, you
50:11
know, and people just get kind of very cynical about, about
50:15
diet and health because it just always seems to be changing.
50:17
And it is obviously it's very complicated.
50:19
But I mean, there are, there are certain things out there which
50:21
we can say with a fair, fair degree of confidence, it seems.
50:25
So like, how do you how do you address this this issue?
50:28
I think it's a really important problem in terms of public
50:33
trust. It's a problem because also
50:35
we're very cautious as scientists.
50:38
And as you've seen, even for me to say today, we often talk in
50:41
very cautious tones. It might be maybe association.
50:45
We don't talk in bold tones that you see a lot of people on
50:48
social media talk about. Also, our food landscape is
50:51
changing. Food is changing.
50:53
So margarine 50 years ago was packed full of trans fats, which
50:58
was created using a process that the food industry used called
51:01
partial hydrogenation. Trans fats are really bad for
51:04
us. So yes, 50 years ago margarine
51:07
was really bad for us. The food industry no longer uses
51:10
the process of partial hydrogenation.
51:12
Margarines, or spreads as we call them now, do not contain
51:16
trans fats. They contain healthy seed oils
51:19
that are processed in such a way that I believe they're healthy
51:21
for us. And so you could have a headline
51:24
in a newspaper saying, oh, the scientists have changed their
51:27
mind again, margarines are healthy for us.
51:29
They told us in the past they were unhealthy.
51:31
Yes, they were unhealthy in the past because they have trans
51:34
fats. Now they don't.
51:36
The other issue we have is there's lots of different ways
51:38
of interpreting the evidence. And there was a study that came
51:41
out, gosh, it was probably about 10 years ago, and they'd looked
51:45
at saturated fat compared to other fats.
51:48
And the next day there was on the front cover of one newspaper
51:52
in the UK and on the front cover of another, a newspaper in the
51:57
UK, two headlines related to this study.
52:00
One of them was saying saturated fats found to be healthy, the
52:05
other one saying saturated fats found to be unhealthy.
52:08
I mean not word for by word. No one's both right, were they?
52:12
That would be typical science if they were both right and.
52:15
Just they were both right and the reason they were both right
52:19
because it's instead of what? And it was a study that had
52:23
looked at saturated fat replacing trans fats, which we
52:27
know is really bad, or replacing polyunsaturated fats or
52:31
monounsaturated fats that we know are really good.
52:34
Now, when you compared saturated fat to trans fats, saturated
52:38
fats came out better for us because trans fats are just so
52:42
bad. When you compared saturated fat
52:44
to the mono or polyunsaturated fats, saturated fats came out
52:48
worse for us. So actually they were correct
52:51
headlines from the same study. But it's confusing people and
52:56
this is where it becomes really difficult.
52:58
And this is what create creates that mistrust as well.
53:02
I don't have the answer to how we get round that as academics,
53:05
as scientists, we need to communicate with the media a lot
53:09
more. We need to communicate on social
53:11
media as well. We need to put ourselves out
53:13
there. It comes at a risk.
53:14
It comes at a risk to the fact that also we are very cautious.
53:18
And I think it's so important and I think in the world of the
53:21
discourses happening around ultra processed food, it's
53:24
becoming more and more important because the arguments around
53:27
ultra processed food is so polarized.
53:30
You have certain personalities like Chris Van Tolken, for
53:33
example, who's fighting a really good fight, but unfortunately I
53:36
think it's demonizing far too much food.
53:39
And then you have certain scientists, nutrition
53:41
scientists, who are so anti the term UPF that are therefore
53:47
creating confusion. Are they good for us?
53:49
Aren't they good for us? And This is why I think it's
53:52
really important. As scientists we say to people,
53:54
OK, here's what the problem is. When you process a food, this is
53:58
what happens. You change the nutrients.
53:59
Heavily processed foods tend to be higher in salt, sugar,
54:02
saturated fat. They tend to be lower in
54:04
polyphenols, they tend to be lower in fibre.
54:07
They tend to have additives and emulsifies, but also what else
54:11
changes. When you process a food, you
54:13
change the food structure, you change the way therefore that
54:17
your body metabolises it. You change the way you absorb
54:21
it, you change your hunger signals, you change the pace at
54:24
which you eat it. And I think this is where it
54:28
becomes complex, but it's actually really important that
54:32
we try and find a way to kind of cut through some of the
54:35
miscommunication and educate people.
54:38
And, and I mean, this is something that I'm very
54:40
passionate about because I spent a lot of time researching how
54:43
food structure is changed via processing and can have a
54:47
subsequent impact on our health. Yeah, because structures,
54:51
structure is really important, right.
54:52
I mean, it's not like, because I'm, there's various supplements
54:55
out there like fuel and I won't ask you to comment on particular
54:57
commercial products, but like they just, they just add
55:00
together all of the chemicals and all of the different
55:02
ingredients that might have been in a meal in powdered form and
55:05
you mix it up with hot water and that's supposedly a meal, right?
55:08
But this I think I was thinking, well, you know, I'm not
55:11
chemophobic. I believe in science.
55:13
So surely that is the same as a meal.
55:14
It's nutritionally, you know, 100% equivalent.
55:17
But something is lost though, and that's the structure, is it?
55:20
Absolutely. So when I think about what
55:22
impacts the helpfulness of a food, so how a food impacts our
55:25
health, I think about three factors.
55:27
I think about the nutrients, so fat, protein, fibre,
55:30
carbohydrate. I think about what are those
55:32
other 54,000 chemicals that are in the food.
55:35
But I think lastly and mostly, what about the structure of that
55:38
food, because the structure and we call this the food matrix,
55:42
modulates how those chemicals and how those nutrients will
55:45
impact our health. And so I can give you a couple
55:48
of examples from my own randomized control trials that
55:50
I've run. So I've run trials, for example,
55:53
where we feed people whole almonds or we feed them ground
55:56
almonds. So these are two foods that have
55:59
identical backer pack labelling. These two foods have identical
56:05
ingredients. All you've done is change the
56:08
structure. So with the ground ones, you
56:10
finely ground them so you burst all of the cells.
56:14
So all of the cell walls are broken, so all of the fat and
56:17
nutrients inside those cells is released.
56:20
And by the way, cell walls is what fibre is, which is why
56:23
fibre has a really important structural role, not just as a
56:26
powder to add into your diet, but actually the structural role
56:29
it plays within a plant. So then and then you've got your
56:32
whole almonds and what we did is we fed to people on one occasion
56:36
whole almonds, on another occasion the ground almonds and
56:39
we looked at various factors. We also fed them over a period
56:42
of time to look at how much of the calories are absorbed from
56:45
them both. When you consume whole almonds,
56:48
about 30% of the calories are excreted compared to alma flour
56:52
where it's all absorbed. And this is because the fibre
56:56
which is the cell walls remains largely intact.
57:00
So when you eat of those nuts, and this applies to many foods,
57:04
you break up some of the cell walls.
57:07
But the cells of almonds are tiny.
57:09
They're about 10 microns. They're smaller than a grain of
57:11
sand. The point at which you swallow
57:14
most foods is a particle size of about 1 millimetre.
57:18
And we've done this. We do lots of these chew and
57:20
spit studies. So I get people at the point at
57:22
which they're about to swallow, they spit out what's in their
57:26
mouth. I love.
57:27
It. Wow, they honestly mark, they're
57:29
disgusting. I've looked at people's poo,
57:31
people's wee, people's blood. I want.
57:33
I want your job, it's so nice. Fortunately I have wonderful
57:37
researchers that do it now, but I've done my time in the lab
57:40
doing this, I tell you, and there's something very intimate
57:42
actually when someone's spitting.
57:45
Anyway, we've analysed these two and spit samples and they're
57:48
about 1 millimetre. So you're swallowing particles
57:50
about 1 millimetre size. So within that you've got
57:53
hundreds and hundreds of intact cells where the fibre wall is
57:58
protecting them from digestion. So what's happening is, yes, you
58:01
do get some more digestion, the gastrointestinal tract, but
58:05
they're absorbed really slowly. They're absorbed slower down the
58:08
gastrointestinal tract, which has more of your fullness
58:11
receptors. So it's more got more GLP
58:14
receptors lower down the gastrointestinal tract.
58:16
So it's feeding back saying well I'm fuller because it's being
58:19
absorbed lower down and you're getting a lot of calories
58:22
excreted. Yet on the back of pack
58:24
labelling, it's just it's 100% almonds, it's the same fat, the
58:29
same protein, the same 5, the same carbohydrate.
58:32
We see the same with porridge. I'd done a study where we fed
58:35
people large porridge and then we just literally ground it down
58:38
to smaller particles. You see 100% difference in some
58:42
of the gut hormone responses between the large porridge and
58:45
the small porridge. You see a 50% difference in the
58:48
post meal glucose response to that blood sugar response with
58:52
the smaller particles giving a bigger peak, which we know is
58:55
less favourable because then you feel less full for longer
58:58
etcetera. Compared to the big particles.
59:00
We see a difference again and where it's absorbed in the gut,
59:03
but again, and these two foods would say they are identical in
59:07
terms of their composition. And This is why structure is
59:10
really important. And one of my favourite
59:13
nutrition studies of all time was actually one that looked at
59:17
this and looked at this in relation to the structure of the
59:20
food, how full people felt and how fast they ate the food.
59:25
And this was a study that was done in 1977.
59:27
It was published in The Lancet. It was one of the first
59:30
nutrition studies to be published in The Lancet because
59:33
nutrition science back then was considered the poor man science.
59:35
Unfortunately it still is somewhat.
59:38
And they fed people 50 grams of carbohydrate either from a whole
59:42
apples or apple puree where they literally just pureed the apple,
59:47
or from apple juice. The whole apples and the apple
59:50
puree had identical nutrient composition.
59:54
The apple juice had the same amount of carbohydrate but had
59:57
the fibre taken out. So you've got the whole apples
1:00:01
that's got the intact fibre. You've got the apple puree
1:00:04
that's got that fibre kind of cell wall element broken down.
1:00:07
Then you've got the apple juice that's had the fibre taken away,
1:00:09
but they've all got 50 grams carbohydrate.
1:00:12
And so you've got these three foods that are all with the same
1:00:15
amount of carbohydrate. But what happens is is that you
1:00:19
consume the whole apple. Lots more slowly.
1:00:24
So they looked at how fast people consumed it, and what
1:00:26
they saw was that the whole apple people are consuming about
1:00:30
three times more slowly than the apple puree.
1:00:34
And then the apple puree. They're consuming more slowly
1:00:36
than the apple juice. They're rapidly drinking the
1:00:38
apple juice. They're then consuming the apple
1:00:42
puree and then the whole apples. What this results in is
1:00:47
differences in feeling of fullness later on, as well as
1:00:50
differences in the circulating blood glucose response.
1:00:52
So in this study, what they did is they asked people come back
1:00:55
the next day and I want you to consume these in exactly the
1:00:58
same time. And so when they asked people to
1:01:01
consume them during the same time, so consume the apple
1:01:04
juice, the apple puree, and the whole apples in 15 minutes, they
1:01:07
still saw this big difference in people's feeling of fullness,
1:01:11
that people having the whole apple felt twice as full as
1:01:15
those people consuming the apple puree, even though essentially
1:01:19
it's the same food. And the reason that this is
1:01:22
important and relevant to what we're eating today is because it
1:01:26
is the texture of the food that is modulating the speed at which
1:01:30
we're eating it. But even independent of the
1:01:33
speed, how we metabolize it and our feelings of fullness.
1:01:37
And this is really important because a lot of processed food
1:01:41
is changed in such a way that the texture is changed.
1:01:44
So a lot of processed foods tends to be soft.
1:01:47
Soft food we eat a lot more quickly than hard food.
1:01:51
And we know again from clinical trials that the faster you eat
1:01:54
your food, the more calories you consume, the greater your
1:01:58
chances are of obesity and metabolic ill health.
1:02:02
And there's some lovely trials that have shown that if you can
1:02:05
reduce the speed at which you eat your food by just 20%, so
1:02:09
slow down your breakfast from 10 minutes to 12 minutes, for
1:02:12
example, subconsciously without even thinking about it, you
1:02:15
would reduce your energy intake by about 15%.
1:02:19
And I love this because it shows the power of how you eat rather
1:02:23
than just what you eat. But it also shows the subtleties
1:02:27
that we need to be thinking about when we think about food
1:02:29
processing. That it's not all about that
1:02:31
evil additive or emulsifier, that the structure and the
1:02:35
texture of the food that's been changed through processing has a
1:02:38
big impact. It has an impact because it
1:02:40
changes how much of the nutrient you absorb, which we know from
1:02:43
the almond work, how quickly it's absorbed, which we know
1:02:46
from our porridge work, and it also changes the speed at which
1:02:51
we're eating and our metabolic responses and so much more.
1:02:55
Wow that is amazing and what a Tour de force.
1:02:57
Thank you. Unclear though whether we should
1:02:59
have the bad idea of food processing, food processing
1:03:02
being bad, or food processing being good, because the answer
1:03:04
seems to be it's complicated. The answer, it's a double edged
1:03:08
sword is what I would say that food processing in my opinion is
1:03:13
not bad as a whole, but that we have to be very mindful of how
1:03:18
much the food is processed in a way that might negatively impact
1:03:22
our health. And that if the food structure
1:03:24
has been destroyed, if it does have additives and emulsifiers
1:03:27
that we believe are harmful to us, then yes, that's been
1:03:31
processed in a way that is unfavourable.
1:03:33
But that not all processed food is bad.
1:03:35
And actually, we've done a body of research at Zowe where we've
1:03:39
looked at how much of the food that we're eating is processed
1:03:42
in such a way that we do think it's harmful.
1:03:45
And instead of seeing seeing that 60% of our food is harmful,
1:03:48
we see that it's about 20% of the food that's processed would
1:03:53
fall into what we call a high risk category.
1:03:56
And this is using this new Zowe processing score that we've
1:03:58
developed that incorporates all the features that I believe are
1:04:02
important in terms of how processing impacts our help.
1:04:05
So features like what kinds of additives are in there, not just
1:04:09
does it have an additive, but what types of additives, how the
1:04:12
food structure has been changed to impact the rate at which we
1:04:15
eat the food food. And also is that food hyper
1:04:17
palatable? Does it have a mix of nutrients
1:04:19
that we know encourage us to over consume that food?
1:04:24
So you're you're replacing the Nova classification score with
1:04:26
this. Well, I'd love, we'd love to.
1:04:28
In our app, we're using the Zoe processing food score.
1:04:32
We spent the last year developing this and it's based
1:04:35
on what I believe is most important when we think about
1:04:38
food processing, how it relates to health.
1:04:40
We've just finished validating this from our Zoe predict
1:04:43
cohort. So in thousands of people
1:04:45
looking at the relationship between how much of the food
1:04:48
they consume that would fall into this high risk category
1:04:51
using our definition and how that relates to health outcomes
1:04:55
versus Nova. So yes, that would I would love
1:04:59
that. OK, well, maybe we'll have the
1:05:01
producer, Rob, you're not allowed to talk.
1:05:02
But can you not say, well is, is the bad idea of ultra processed
1:05:06
foods being bad? Is that, is that, is that
1:05:08
sufficient? He's given us a nod.
1:05:11
So I think I think we're good to go.
1:05:13
So thank you again, Sarah Berry for joining us on saving the
1:05:16
world from bad ideas. As I say, it's been it's been a
1:05:18
Tour de force and we'd love to have you back some some points,
1:05:21
but for now, thank you very much.
1:05:23
Pleasure. Thank you for having me.
1:05:28
Thanks so much for listening to Saving the World from Bad Ideas,
1:05:30
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1:05:35
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