Sunlight: A Lot More Than Just Vitamin D

October 10, 2016

Sunlight: A Lot More Than Just Vitamin D


 Reference: Science News, Cell,     

You know that we need Vitamin D and that we get it only from sunshine. (Well, a tiny bit is artificially added to milk and Cod Liver Oil has some in it). And you know that, in Wisconsin, we stop making Vitamin D about October 1, not because it's cold and cloudy but because the angle of the sun is now so low that almost all UVB is filtered out by the atmosphere. And you know that you need to have a blood level of at least 32 ng and optimally in the range of 45-55, which most folks can achieve with 20,000 iu a week. 

Ok, so far, so good. But we feel different in winter, and the human body makes a whole host of other chemicals and hormones in response to sunlight. If you feel that your mood changes in the winter, read on. Here is the explanation. First of all, as reported in Science News, elegant research in the journal, Cell, shows that mice, exposed to UVB radiation increase the amount of β-endorphin in their blood. It goes away in about a week. β-endorphin isn't there for your pleasure seeking feelings, it's present throughout your body and plays a role in many processes, including part of your immune balancing system. When the mice were given a blocking drug to morphine called naloxone, they actually showed some signs of withdrawal, as though they were habituated or addicted to the sunlight. Don't you feel good when you get good bright sunlight? Serotonin is one of your happy hormones

Bit by bit we are assembling evidence that sunlight makes for more serotonin. Whether it's through Vitamin D production, leading to more serotonin, or other complex processes, we aren't sure, but sunlight does cheer you up. Oxytocin is your bonding hormone. Without it, mother mice reject their babies. With it, we bond and feel great attachment to our mates and our offspring. Again, sunlight appears to increase oxytocin release

 Finally, there is dopamine. It is part of our portfolio of happy hormones. It appears that you might need at least 30 minutes to increase dopamine receptors and thereby increase sensitivity to dopamine, but sunlight does it. So what's a person to do in Wisconsin to keep our mood up when the sun goes down? Well, first and foremost, think about the portfolio of hormones that are affected by sunlight and consider other means by which you can increase them. A good night's sleep, good exercise, entertaining positive thinking, keeping up on supplementation of Vitamin D, enjoying the pleasure of good friends, participating in strong community and loving family...all seems to make good sense, and good hormones. 

 WWW.What will work for me? I take 20,000 IU of D a week and 50,000 IU when I get a cold. I try to keep exercising regularly so that I get sweaty enough to take a shower. I haven't had many vegetable oils, but I've had lots of vegetables. But I'm really thinking about is a nice trip to someplace sunny. Wouldn't that be nice? Visualize that 5 mile long beach and how good you feel when you are walking on it. 

 Pop Quiz

1. β-endorphin levels go up in humans with exposure to sunlight? T or F ‪                         Answer:  Oops, maybe, maybe not. It's proven in mice. It's even blocked with morphine blockers in mice. And humans and mice overlap a lot. But the research was in mice. Not humans. It confirms our hunch about how we feel with sunlight, but it's not proven in humans yet. 

2. We go into withdrawal when we stop getting sunlight? T or F?                         Answer: Well, it's true for me. But we don't have that research in humans. If you answered true, you may well reflect the majority opinion of how we all feel as the days get shorter and sunlight weaker. 

 ‪3. There are other hormones released on exposure to sunlight. T or F?                       Answer:  True. Particularly the "happy hormones", oxytocin, serotonin, dopamine. ‪

4. You can't make much Vitamin D after October 1 in Wisconsin. T or F?                    Answer:  True. Now, if you are particularly sun sensitive and have very fair skin, and originate from far Northern European countries, your skin is likely still able to pick up some D at midday for a couple more weeks. You won't burn. If you have olive skin or darker, your chance is past. Dark Africans need 6 times the amount of sunlight to get to the same D level. Older folks getting closer to 70 will need as much as 4-5 times the amount of sunlight to have the same D effect as younger folks. 

5. When I take Vitamin D, I feel happy. T or F?                      Answer:   Well, not really. Except for that you remembered to do it. D may help you make more serotonin and prevent warding off the winter blues, but you don't feel it immediately. What is more likely is that you don't descend into January depression. It's harder to prove the absence of a negative versus the presence of a positive.