Latest / Hardiness with Dr Paul Taylor / Your water bottle is influencing your response to stress: Wisdom Wednesdays

Transcript

Your water bottle is influencing your response to stress: Wisdom Wednesdays · Hardiness with Dr Paul Taylor

• 0:05
  Speaker 1: Everyone, Welcome to another edition of Wisdom Wednesdays. Picture two
• 0:11
  Speaker 1: versions of you. Both have the same job, the same sleep,
• 0:14
  Speaker 1: the same fitness, same everything, except one of you drinks
• 0:18
  Speaker 1: about a leader of water a day and the other
• 0:21
  Speaker 1: one next close to four leaters just to have it.
• 0:26
  Speaker 1: That's the only difference. Now you get a curveball, a
• 0:29
  Speaker 1: stressful curveball, whether it's a tough conversation, maybe a public
• 0:34
  Speaker 1: presentation if you don't like it, or you know something
• 0:36
  Speaker 1: thinks something stressful. Same stressors, same anxiety, same sweaty pans,
• 0:43
  Speaker 1: same heartbeat in your chest. But underneath, one version of
• 0:47
  Speaker 1: you is dumping about fifty five percent more cortisol into
• 0:52
  Speaker 1: the bloodstream than the other, and you can't feel anything different. Now,
• 0:58
  Speaker 1: this is not a thought experiment. It's a study that
• 1:00
  Speaker 1: came out this year and it's super, super interesting, So
• 1:04
  Speaker 1: let's dive into it. So I've talked a lot about cortisol.
• 1:08
  Speaker 1: You know, if you've listened to this podcast, it's the
• 1:11
  Speaker 1: main hormone of your stress response. It's released from your
• 1:14
  Speaker 1: drenal glands whenever your brain decides that something is a threat.
• 1:19
  Speaker 1: But it is also the hormone that gets you to
• 1:22
  Speaker 1: wake up and gives your energy for the day. So
• 1:25
  Speaker 1: in a healthy system, cortisol spikes when you need it.
• 1:28
  Speaker 1: That's why it tends to peak whenever you're just waking up.
• 1:32
  Speaker 1: But when there's stressful events, you get a spike. It
• 1:35
  Speaker 1: sharpens you up, and then it comes back down once
• 1:38
  Speaker 1: the threat has passed. Now that rise and fall, that's normal,
• 1:42
  Speaker 1: it's adaptive. It's the whole story that I bang on
• 1:46
  Speaker 1: about about hormesis and that normal stress response. But here's
• 1:51
  Speaker 1: the thing that this new study zeros in on the
• 1:53
  Speaker 1: size of the cortisol spike. Isn't about how it's threatening,
• 1:57
  Speaker 1: or isn't just about how threatening the situation is. It
• 2:00
  Speaker 1: turns out that your water intake can significantly turn that
• 2:05
  Speaker 1: dial up or down, and you don't really feel it
• 2:09
  Speaker 1: happening because the feeling of stress and the hormone driving
• 2:12
  Speaker 1: it can actually come apart the feeling and the hormone.
• 2:16
  Speaker 1: So why would that even be biologically plausible. Well, it's
• 2:20
  Speaker 1: because the system that manages your body water and the
• 2:24
  Speaker 1: system that manages cortisol shure the same wiring in the brain. Now,
• 2:28
  Speaker 1: the hormone that regulates body fluid is called vasopressing. You
• 2:31
  Speaker 1: may have heard of it. It's the one that tells
• 2:33
  Speaker 1: your kidneys to hold onto water when you're running low,
• 2:36
  Speaker 1: and it also nudges your proputary gland to kick off
• 2:39
  Speaker 1: the cortizole cascade. So it's the same messenger, but it
• 2:43
  Speaker 1: has two different jobs. So if you're chronically dehydrated, that
• 2:49
  Speaker 1: pathway for stress hormones is already a bit more switched on,
• 2:53
  Speaker 1: and that's even before stress shows up. So this study
• 2:57
  Speaker 1: came out of Liverpool, John Moore's Universe. It's published in
• 3:01
  Speaker 1: the Journal of Applied Physiology, and it was a really
• 3:04
  Speaker 1: cool piece of work, so let's dive into it. What
• 3:06
  Speaker 1: they did is they screened over sixty healthy adults and
• 3:10
  Speaker 1: they pulled out two groups from the extreme end of
• 3:13
  Speaker 1: a national hydration database. Sixteen people who habitually drank low
• 3:17
  Speaker 1: amounts of fluid, averaging just over a leader a day,
• 3:21
  Speaker 1: and sixteen people who were super water drinkers. They averaged
• 3:25
  Speaker 1: about just over four leaders a day. And they matched
• 3:28
  Speaker 1: them for aids, for sex, for anxiety, for sleep quality,
• 3:32
  Speaker 1: for stress levels, all of these things. So they looked
• 3:35
  Speaker 1: very very similar on paper apart from their habitual fluid intake,
• 3:40
  Speaker 1: and for a week, everyone wanted, did their intake with
• 3:42
  Speaker 1: a smart bottle, and the researchers confirmed using their urine
• 3:46
  Speaker 1: concentration that the low water group really were under hydrated
• 3:51
  Speaker 1: and that the high water group were what we call hyperhydrated. Now,
• 3:55
  Speaker 1: fifteen out of sixteen in the low group showed suboptimal
• 4:00
  Speaker 1: in the morning and testing and fourteen out of sixteen
• 4:03
  Speaker 1: and the high group didn't. Right, then everybody went through
• 4:07
  Speaker 1: what's known as the Trier social stress test. If you've
• 4:11
  Speaker 1: never heard of it, this is a gold standard laboratory
• 4:15
  Speaker 1: stressor a bunch of psychological stressors that psychologists use, right,
• 4:19
  Speaker 1: and it involves things such as you go into a room,
• 4:23
  Speaker 1: you're standing in front of two strangers who just don't
• 4:26
  Speaker 1: react to anything that you say. You do a mock
• 4:29
  Speaker 1: job interviewed, followed by counting backwards in seven out loud
• 4:33
  Speaker 1: on their time pressure. We're really getting hassled. So there's
• 4:36
  Speaker 1: a number of different things that go on that reliably
• 4:39
  Speaker 1: makes people's cortisol rise in the lab, and it's about
• 4:43
  Speaker 1: as close as you can get to a really threatening
• 4:46
  Speaker 1: social moment. Right. They then took the live of samples before, during,
• 4:51
  Speaker 1: and after and the event, and they tracked their cortisol,
• 4:54
  Speaker 1: the heart rate, and self reported anxiety the whole way through.
• 4:58
  Speaker 1: And here's where it gets into on everything that participants
• 5:02
  Speaker 1: could consciously report. The two groups were identical and reported
• 5:07
  Speaker 1: anxiety went up by about the same amount in both groups.
• 5:10
  Speaker 1: Heart rate went up by about the same amount in
• 5:12
  Speaker 1: both groups. So if you were just starting watching both
• 5:15
  Speaker 1: groups go through this, you would not have been able
• 5:17
  Speaker 1: to tell the low or the under hydrated people from
• 5:22
  Speaker 1: the well hydrated one. The only thing that was different
• 5:25
  Speaker 1: was the cortisol levels. In the low hydration group, cordisole
• 5:30
  Speaker 1: rose significantly after the test, and in the high water
• 5:34
  Speaker 1: group it barely moved. And when they measured the actual
• 5:37
  Speaker 1: size of the rise the pre test to the peak afterwards,
• 5:42
  Speaker 1: the low drinkers average about six point two animals per
• 5:45
  Speaker 1: leader of cortisol and the high drinkers about four. Now
• 5:49
  Speaker 1: that's a fifty five percent difference, and it wasn't just
• 5:53
  Speaker 1: a two group average. The more concentrated someone's urine was,
• 5:57
  Speaker 1: the bigger their cortisol spike. So what we call is
• 6:00
  Speaker 1: that that dose response was I've talked about before, and
• 6:03
  Speaker 1: that was right across the whole sample, and it was
• 6:06
  Speaker 1: a fairly strong correlation. And I think the other thing
• 6:09
  Speaker 1: that I picked up when looking at the graphs is
• 6:12
  Speaker 1: that even the baseline cortisol was higher in the low drinkers,
• 6:17
  Speaker 1: So being dehydrated actually is a signal for your body
• 6:22
  Speaker 1: to release stress hormones, right. And what they also did
• 6:27
  Speaker 1: was they measured the urine using a simple urine color chart.
• 6:30
  Speaker 1: It's the one that athletes choose all the time. You
• 6:33
  Speaker 1: may have seen it. It goes from very peel to
• 6:35
  Speaker 1: kind of a darker orange or almost a brownie orange.
• 6:39
  Speaker 1: And the people who showed up with darker urine in
• 6:41
  Speaker 1: the morning the test had meaningfully bigger cortisol spikes than
• 6:44
  Speaker 1: the people who showed up clear, right. So you don't
• 6:48
  Speaker 1: need really sensitive equipment to this. This is just something
• 6:52
  Speaker 1: that you can eyeball and the toilet bowl every single morning. Right.
• 6:57
  Speaker 1: We do need to acknowledge that the study was pretty
• 6:59
  Speaker 1: small thirty two people, not not a couple of thousand people.
• 7:04
  Speaker 1: But I think that the design of the study was really,
• 7:09
  Speaker 1: really robust, and there was also a plausible biological mechanism
• 7:15
  Speaker 1: because vasopressin actually not only does it is involved in
• 7:22
  Speaker 1: hydration status, but it is also a part of the
• 7:25
  Speaker 1: stress response, and we know that vasopressin, as well as
• 7:29
  Speaker 1: acting on the peture tary, can also directly act on
• 7:33
  Speaker 1: the adrenal cortex, which is the part of the adrenal
• 7:36
  Speaker 1: glands that actually produces cortisol. So this for me is
• 7:41
  Speaker 1: a real, very clear take home in this study is
• 7:46
  Speaker 1: that we need to be hydrated. We need to pay
• 7:49
  Speaker 1: attention to our hydration levels, because dehydration actually is a
• 7:56
  Speaker 1: stressor on the body and it will amplify psychological stress
• 8:01
  Speaker 1: that you experience and as well thinking about it, and
• 8:05
  Speaker 1: we know from exercise if you're dehydrated during exercise, you
• 8:09
  Speaker 1: produce more cortisol as well. Those studies have been around
• 8:11
  Speaker 1: for decades, but now it seems that psychological stress has
• 8:15
  Speaker 1: the same interaction with your hydration level. So what's the
• 8:19
  Speaker 1: take home. Look, I have a simple run that I've
• 8:22
  Speaker 1: done for years. Try to pay reasonably clear by nine am.
• 8:27
  Speaker 1: I drink a fur bit in the morning and try
• 8:29
  Speaker 1: to keep it that way for the rest of the day.
• 8:31
  Speaker 1: If your urine is dark and then that is a
• 8:34
  Speaker 1: bad thing. And it's really about making sure that we
• 8:38
  Speaker 1: are drinking enough water throughout the day. And you've got
• 8:42
  Speaker 1: to be aware that you can't just skull a pint
• 8:45
  Speaker 1: of water and be good. Because your kidneys don't filter
• 8:48
  Speaker 1: it that efficiently, a lot of it will just get
• 8:51
  Speaker 1: paid out. It's about sipping that water pretty consistently throughout
• 8:55
  Speaker 1: the day and that if you stay hydrated, will help
• 8:58
  Speaker 1: to keep your stress levels. That's it for this week, folks,
• 9:02
  Speaker 1: Catch you next time. Mhm.