1 00:00:05,840 --> 00:00:09,000 Speaker 1: Hey, everybody, welcome to another edition of Wisdom Wednesdays. 2 00:00:09,080 --> 00:00:11,080 Speaker 2: Today we're going to talk about something that's pretty. 3 00:00:10,840 --> 00:00:14,080 Speaker 1: Simple but has a big impact on our biology, and 4 00:00:14,120 --> 00:00:17,880 Speaker 1: that is sunshine. I've just read a pretty interesting paper 5 00:00:18,000 --> 00:00:22,520 Speaker 1: that's been published in the Innovations in Clinical Neuroscience. The 6 00:00:22,520 --> 00:00:27,200 Speaker 1: title of the paper Sunshine, Serotonin and Skin A Partial 7 00:00:27,400 --> 00:00:32,120 Speaker 1: Explanation for Seasonal Patterns in Psychopathology. It's a bit of 8 00:00:32,200 --> 00:00:36,000 Speaker 1: a mouthful, but basically it explores something I think we 9 00:00:36,280 --> 00:00:40,879 Speaker 1: massively underestimate in modern health conversations, and that is the 10 00:00:40,920 --> 00:00:46,560 Speaker 1: relationship between light exposure, serotonin, mood disorders, and even suicide. 11 00:00:46,920 --> 00:00:50,839 Speaker 1: Now we've known for a long time that psychiatric symptoms 12 00:00:50,960 --> 00:00:54,840 Speaker 1: can follow seasonal patterns, and it's even mentioned in the 13 00:00:54,920 --> 00:01:00,320 Speaker 1: DSM five. It includes a with seasonal pattern specifier for 14 00:01:00,480 --> 00:01:05,280 Speaker 1: depressive disorders because we see that mood disorders, anxiety disorders, 15 00:01:05,319 --> 00:01:11,160 Speaker 1: and even completed suicide they show fluctuations across the year. 16 00:01:11,880 --> 00:01:13,320 Speaker 2: Now here's where it gets interesting. 17 00:01:13,520 --> 00:01:18,440 Speaker 1: We've always assumed that the mechanism was primarily through the eyes, 18 00:01:18,920 --> 00:01:21,280 Speaker 1: where a light hits the sun from the sun hits 19 00:01:21,280 --> 00:01:25,600 Speaker 1: the retina and that signal and then travels to something 20 00:01:25,640 --> 00:01:29,959 Speaker 1: called the raffi nuclei and then your serotonin shifts and 21 00:01:29,959 --> 00:01:33,440 Speaker 1: your mood changes, and it's pretty neat, it makes sense. 22 00:01:34,360 --> 00:01:38,520 Speaker 1: But this paper proposes something a bit more intriguing, and 23 00:01:38,560 --> 00:01:42,440 Speaker 1: that is that your skin might be directly involved. And 24 00:01:42,600 --> 00:01:45,000 Speaker 1: it turns out that these seasonal mood changes might not 25 00:01:45,120 --> 00:01:49,320 Speaker 1: just be winter blues. There are a number of large 26 00:01:49,440 --> 00:01:53,160 Speaker 1: research studies that shows that there's worsening depressive symptoms in 27 00:01:53,200 --> 00:01:56,880 Speaker 1: the winter months, and everybody gets that, particularly if you 28 00:01:56,960 --> 00:02:01,040 Speaker 1: live somewhere where it gets dark a lot where I'm from. 29 00:02:01,240 --> 00:02:05,080 Speaker 1: But we know that there's increased anxiety, there's also seasonal 30 00:02:05,120 --> 00:02:10,640 Speaker 1: shifting bipolar disorder, and we also know that serotonin levels 31 00:02:10,639 --> 00:02:15,360 Speaker 1: in healthy individuals also fluctiate seasonally, their lowest in winter 32 00:02:15,520 --> 00:02:18,600 Speaker 1: and their highest and late summer in autumn, and that 33 00:02:18,680 --> 00:02:21,679 Speaker 1: has a big impact on our mood. So clearly there 34 00:02:21,800 --> 00:02:26,559 Speaker 1: is a biological signal that is responding to light availability, 35 00:02:27,560 --> 00:02:29,960 Speaker 1: and this research paper is saying that it's not just 36 00:02:30,120 --> 00:02:33,560 Speaker 1: the eyes that are involved, but also the skin. 37 00:02:34,160 --> 00:02:36,760 Speaker 2: So the researchers high added. 38 00:02:36,480 --> 00:02:42,000 Speaker 1: That human skin contains the machinery necessary to produce serotonin, 39 00:02:42,040 --> 00:02:44,400 Speaker 1: and this is a bit of a game changer. So 40 00:02:44,440 --> 00:02:49,760 Speaker 1: something called tripped upon hydroxyle is. This is the the 41 00:02:49,960 --> 00:02:53,760 Speaker 1: real limiting enzyme for serotonin synthesis. What that means, a 42 00:02:53,880 --> 00:02:56,679 Speaker 1: real limiting enzyme is something that if it's not there, 43 00:02:56,720 --> 00:03:00,440 Speaker 1: if the enzyme is not there, it actually impacts upon 44 00:03:00,480 --> 00:03:04,280 Speaker 1: this pathway. Right, So this trip to pane hydroxylea is 45 00:03:04,520 --> 00:03:10,320 Speaker 1: actually present in our skin. So serotonin itself is finding 46 00:03:10,560 --> 00:03:16,280 Speaker 1: in what are called keratinocytes, and serotonin transporters are present 47 00:03:16,280 --> 00:03:17,840 Speaker 1: there too, So this is in the skin. 48 00:03:18,200 --> 00:03:21,600 Speaker 2: So it turns out your skin isn't just a passive barrier. 49 00:03:22,080 --> 00:03:28,400 Speaker 1: It's actually active neurochemically. And there's actually an evolutionary argument 50 00:03:28,440 --> 00:03:30,000 Speaker 1: for this that they discussed in the paper. 51 00:03:30,639 --> 00:03:32,360 Speaker 2: The brain and the skin. 52 00:03:32,520 --> 00:03:34,760 Speaker 1: The epidermis, that's a layer of the skin sure a 53 00:03:34,880 --> 00:03:40,320 Speaker 1: common embryological organ, and that's called the ectoderm. So there 54 00:03:40,360 --> 00:03:44,960 Speaker 1: are three germ layers that we develop from the ectoderm, 55 00:03:45,000 --> 00:03:47,040 Speaker 1: the endoderm, and the mesoderm. 56 00:03:47,120 --> 00:03:50,000 Speaker 2: So it turns out that our brain and our skin. 57 00:03:50,160 --> 00:03:56,440 Speaker 1: Are actually related biologically at that very very initial level. 58 00:03:56,800 --> 00:04:01,680 Speaker 1: And some researchers suggest that the skin setgic system or 59 00:04:01,760 --> 00:04:06,600 Speaker 1: serotinergic sorry system may be an evolutionary remnant of an 60 00:04:06,800 --> 00:04:11,320 Speaker 1: ancient ancestral peripheral serotonin system. It was just a bit 61 00:04:11,360 --> 00:04:15,920 Speaker 1: of a mouthful to say that. Basically, the skin has 62 00:04:15,960 --> 00:04:17,560 Speaker 1: been involved for millions of years. 63 00:04:18,120 --> 00:04:20,479 Speaker 2: So what they did is one experiment. 64 00:04:20,560 --> 00:04:25,360 Speaker 1: The participants were exposed to light while worrying opaque goggles 65 00:04:25,360 --> 00:04:29,719 Speaker 1: to block retinal input, and even with the eyes basically 66 00:04:29,720 --> 00:04:32,479 Speaker 1: shut down to the light, those who were exposed to 67 00:04:32,600 --> 00:04:36,240 Speaker 1: light had higher serum serotonin levels and it was through 68 00:04:36,320 --> 00:04:41,080 Speaker 1: the skin pathway, and that means that sunlight can directly 69 00:04:41,200 --> 00:04:45,640 Speaker 1: stimulate serotonin production via the skin, and that's probably why 70 00:04:45,680 --> 00:04:49,160 Speaker 1: we all feel a shitload better in the summer, and 71 00:04:49,200 --> 00:04:53,440 Speaker 1: we instinctively seek the sun in winter, and it may 72 00:04:53,480 --> 00:04:57,200 Speaker 1: be that it's just our basic neurobiology that's driving that desire. 73 00:04:57,560 --> 00:05:00,000 Speaker 2: So let's just make the pathway really really simple. 74 00:05:00,279 --> 00:05:03,880 Speaker 1: Sunlight hits the skin and then cutaneous or skin serotonin 75 00:05:03,920 --> 00:05:08,240 Speaker 1: production increases, and then you get systemic shifts in your 76 00:05:08,279 --> 00:05:12,480 Speaker 1: serotonin levels, and then your mood regulation and improves. So 77 00:05:12,680 --> 00:05:17,320 Speaker 1: serotonin isn't just about happiness. It actually regulates mood stability. 78 00:05:17,360 --> 00:05:19,760 Speaker 1: It has an impact on anxiety, It has an impact 79 00:05:19,839 --> 00:05:24,080 Speaker 1: on sleep, on appetite, on impulse control, and all of 80 00:05:24,120 --> 00:05:28,040 Speaker 1: these things are highly highly relevant to psychiatric disorder, so 81 00:05:28,120 --> 00:05:33,040 Speaker 1: impulse control is heavily implicated in ADHD as well. So 82 00:05:33,120 --> 00:05:38,040 Speaker 1: this gives us a partial biological explanation for this sad 83 00:05:38,680 --> 00:05:42,560 Speaker 1: thing that we see seasonal effective disorder and also seasonal 84 00:05:42,600 --> 00:05:47,520 Speaker 1: worsening of depression. Less sunlight equals less photo stimulation, and 85 00:05:47,520 --> 00:05:52,800 Speaker 1: that means lower serotonin. Now let's layer this over circarean biology. 86 00:05:53,320 --> 00:05:58,200 Speaker 1: So light is the primary regulator of your super chismatic nucleus, 87 00:05:58,200 --> 00:05:59,719 Speaker 1: that's the master clock. 88 00:06:00,680 --> 00:06:01,799 Speaker 2: It sits right. 89 00:06:01,640 --> 00:06:06,479 Speaker 1: Behind your forehead, and morning light suppresses melatonin and it 90 00:06:06,560 --> 00:06:10,599 Speaker 1: elevates cortisol. Appropriately, we need cortisol to give us energy 91 00:06:10,640 --> 00:06:15,159 Speaker 1: to attack the day. Daytime light increases alertness and stabilizes mood, 92 00:06:15,480 --> 00:06:19,520 Speaker 1: and then that evening darkness allows melatonin to rise. So 93 00:06:19,600 --> 00:06:23,040 Speaker 1: if we disrupt that pattern with dim days and bright 94 00:06:23,240 --> 00:06:27,080 Speaker 1: nights the lights at night, we dese stabilize our Circian rhythms. 95 00:06:27,240 --> 00:06:29,800 Speaker 1: And I've talked on this podcast many times before about 96 00:06:29,880 --> 00:06:36,600 Speaker 1: what happens when you mess with circarean biology. Basically, you 97 00:06:36,640 --> 00:06:40,880 Speaker 1: significantly increase depression by polar disorder, anxiety, and psychosis, as 98 00:06:40,880 --> 00:06:44,240 Speaker 1: well as a whole heap of physical issues which we 99 00:06:44,279 --> 00:06:47,480 Speaker 1: won't even talk about in this podcast. So light isn't 100 00:06:47,560 --> 00:06:53,000 Speaker 1: just mood decoration, it's a metabolic and psychiatric infrastructure. 101 00:06:53,680 --> 00:06:55,680 Speaker 2: And then we need to talk about vinamin date. 102 00:06:55,800 --> 00:06:59,960 Speaker 1: I have dedicated almost an entire chapter in my new 103 00:07:00,000 --> 00:07:04,680 Speaker 1: book the hardiness effect of vitamin D because it's hugely important. 104 00:07:04,720 --> 00:07:07,440 Speaker 1: It shouldn't actually be called a vitamin. It's actually a 105 00:07:07,560 --> 00:07:12,520 Speaker 1: steroid hormone. And when UVB rays from the sun hit 106 00:07:12,640 --> 00:07:19,200 Speaker 1: your skin, they convert seven at D hydro cholesterol into 107 00:07:19,240 --> 00:07:22,760 Speaker 1: vitamin D three, which is then activated in your liver 108 00:07:22,840 --> 00:07:23,760 Speaker 1: and your kidneys. 109 00:07:24,040 --> 00:07:25,640 Speaker 2: And that active form that comes out. 110 00:07:25,520 --> 00:07:28,640 Speaker 1: Of your living in your kidneys is called calcatrol that 111 00:07:28,720 --> 00:07:33,280 Speaker 1: binds the vitamin D receptors in nearly every tissue in 112 00:07:33,320 --> 00:07:34,200 Speaker 1: your body. 113 00:07:34,880 --> 00:07:37,800 Speaker 2: This is why vitamin D is so important. 114 00:07:38,280 --> 00:07:42,880 Speaker 1: It regulates hundreds and hundreds and likely thousands of genes. 115 00:07:43,040 --> 00:07:44,440 Speaker 2: Research is now discovery. 116 00:07:44,800 --> 00:07:48,840 Speaker 1: We now know that vitamin D influences DNA repair, it 117 00:07:49,200 --> 00:07:52,920 Speaker 1: suppresses inflammation, It has a positive role on the function 118 00:07:53,000 --> 00:07:57,160 Speaker 1: of your mitochondria, It modulates your immune system. It actually 119 00:07:57,200 --> 00:08:03,120 Speaker 1: plays a role in neurotransmitter synthesis, telemere stability, and in autopogy. 120 00:08:03,200 --> 00:08:08,760 Speaker 1: That's kind of cleansing, cellular cleansing, and basically these vinamin 121 00:08:08,880 --> 00:08:13,040 Speaker 1: D receptors that are also present in Brian regions involved 122 00:08:13,040 --> 00:08:16,320 Speaker 1: in mood and cognition. And we see that lower vitamin 123 00:08:16,400 --> 00:08:19,239 Speaker 1: D is associated with high rates of depression, and actually 124 00:08:19,360 --> 00:08:23,840 Speaker 1: interventions using vinamin D for depression are actually pretty successful. 125 00:08:24,200 --> 00:08:25,920 Speaker 2: So here's there's another pathway. 126 00:08:26,200 --> 00:08:31,400 Speaker 1: Sunlight activates UVB or our releases UVB that triggers vitamin 127 00:08:31,480 --> 00:08:34,480 Speaker 1: D synthesis, that regulates our genes and a whole heap 128 00:08:34,559 --> 00:08:37,880 Speaker 1: of other shit, and that lends us leads us to 129 00:08:38,160 --> 00:08:42,640 Speaker 1: a positive mood, lower inflammation, and neuroprotection as well. Now 130 00:08:42,679 --> 00:08:46,760 Speaker 1: remember this sunscreen blocks about ninety five percent of vitamin 131 00:08:46,840 --> 00:08:51,360 Speaker 1: D production, and that leads us to this modern problem. 132 00:08:51,880 --> 00:08:53,640 Speaker 1: And I've read about this in my book I come 133 00:08:53,679 --> 00:08:57,000 Speaker 1: from Northern Ireland with the sun was a mythical creature. 134 00:08:57,520 --> 00:09:00,760 Speaker 1: Anytime it was out, everybody was out with their tops off. 135 00:09:00,960 --> 00:09:02,920 Speaker 1: And then it came to Australia and it was like 136 00:09:02,960 --> 00:09:05,559 Speaker 1: this was something that was evil and to be avoided. 137 00:09:06,040 --> 00:09:10,440 Speaker 1: And that's because obviously of skin cancer. And you know, 138 00:09:10,520 --> 00:09:13,079 Speaker 1: it is right that we can't have too much because 139 00:09:13,080 --> 00:09:15,440 Speaker 1: we increase our risk of skin cancer. But the researcher 140 00:09:15,440 --> 00:09:18,120 Speaker 1: is now showing low vinamin D increases the risk of 141 00:09:18,240 --> 00:09:23,320 Speaker 1: many other cancers. So by avoiding excessive UV, we may 142 00:09:23,400 --> 00:09:28,880 Speaker 1: have drifted into chronic light deficiency and that is associated 143 00:09:28,920 --> 00:09:33,800 Speaker 1: with lower serotonin, disturbed circadian rhythms, lower vitamin D, increased depression, 144 00:09:33,840 --> 00:09:38,880 Speaker 1: increased anxiety, and potential seasonal exacerbation of a whole host 145 00:09:38,920 --> 00:09:43,000 Speaker 1: of psychiatric illnesses. So the solution isn't to go out 146 00:09:43,000 --> 00:09:46,240 Speaker 1: there and just recklessly expose yourself to the sun. It's 147 00:09:46,240 --> 00:09:51,520 Speaker 1: about intelligent exposure. It's about getting enough but not getting 148 00:09:51,520 --> 00:09:51,960 Speaker 1: too much. 149 00:09:52,000 --> 00:09:54,040 Speaker 2: It's really the Goldilocks effect. 150 00:09:54,920 --> 00:09:57,520 Speaker 1: So it's really to b see if it's get regular 151 00:09:57,760 --> 00:10:01,199 Speaker 1: morning light exposure when the sun isn't who's strong, aim 152 00:10:01,280 --> 00:10:04,400 Speaker 1: for short, sensible mid day sun exposure based on your 153 00:10:04,440 --> 00:10:07,079 Speaker 1: skin type. You can actually look that up. I think 154 00:10:07,120 --> 00:10:11,600 Speaker 1: it's called the Fitzpatrick skiel. And obviously if you're peel 155 00:10:12,040 --> 00:10:14,000 Speaker 1: you need less time in the sun than if you've 156 00:10:14,080 --> 00:10:16,679 Speaker 1: got dark skin. But for me, the big thing, get 157 00:10:16,720 --> 00:10:20,680 Speaker 1: your vimin le D levels tested. Don't guess, get them tested. 158 00:10:20,760 --> 00:10:24,840 Speaker 1: Go to Omega quant O M E G A q 159 00:10:25,040 --> 00:10:28,080 Speaker 1: U A N T and for about sixty Australian dollars 160 00:10:28,160 --> 00:10:30,040 Speaker 1: you can get it tested. I got no association with 161 00:10:30,080 --> 00:10:31,760 Speaker 1: these guys. I just love that they will test your 162 00:10:31,840 --> 00:10:35,360 Speaker 1: vinmin D levels. They'll also test your Omega three fatty acids, 163 00:10:35,400 --> 00:10:39,400 Speaker 1: which you should do while you're at it. So that 164 00:10:39,679 --> 00:10:42,640 Speaker 1: is pretty much that for this week, folks. We need 165 00:10:42,720 --> 00:10:46,920 Speaker 1: to get enough sun exposure and overall light exposure and 166 00:10:46,960 --> 00:10:49,480 Speaker 1: your brain and your mood will thank you for it. 167 00:10:49,800 --> 00:10:52,000 Speaker 2: That's it for this week, folks. Catch you next time.