I am listening to this podcast about pigs, pork, lard, skin care products, and more:
Somewhere around the 20 minute mark, he says that, for vitamin D absorption/creation, we shouldn’t wear sunglasses, because we get a lot of vitamin D through the eyes.
Anyone ever heard of this? (I have not.) Should I stop wearing my sunglasses so I get more natural vitamin D?
Depends. Do you think it’s sun exposure in these days of more extreme solar radiation that leads to so many cataracts (and skin cancers) or do you think it’s something else, and we’re damaging ourselves by denying our skin and eyes that UV radiation that produces vitamin D. Seems to be plenty of fodder on either side of the argument.
Personally, all my skin cancers have occurred on my face and neck, some in places the sun doesn’t reach and all of them following hitting max rad limits during xrays and MRI procedures of my neck and upper back. Not to say overexposure to the sun doesn’t play a part, but I’m a lot more suspicious of medical procedures than I am of the sun.
There are tantalising bits of research showing that cataracts and cancers may be the result of damage by advanced glycation end-products (AGE’s), resulting from a high-glucose diet.
Low cholesterol levels have been known since the 1980’s to associate with a greater risk of cancers. Nina Teicholz has documents showing that the NIH in the U.S. actually called a conference to discuss the data, and the decision was made that lowering cardiovascular risk was so important that the official advice should not “confuse” the public by mentioning the cancer risk.
It is also well-known nowadays that cholesterol is a precursor to Vitamin D (as well as many important hormones), so a cholesterol-lowering diet is counter-productive in many ways.
Anecdotally, I can say from personal experience that before keto my skin I had got so that I would burn after about half an hour in the sun, even with SPF 100 or 150 lotion on. (By contrast, in my youth, I used to be able to stay out in the sun for hours with SPF of 36 or so.) I noticed, however, that after a year or so on a keto diet, I could spend around four hours in the sun mowing the lawn, wearing nothing but cutoff shorts, and never burn. I’m sure there’s a limit there, somewhere (after all, I am Scottish, English, Irish, Welsh, and Cornish, so I never tan, only burn), but the limit is a lot further out than it was pre-keto.
Michael Holick (MD, PhD)'s books are well worth reading on the topic of Vitamin D and in the essential role of sunshine. In short: get daily sunshine exposure - but never enough to burn skin. The truly dangerous skin cancers are far more likely to appear in body locations where the sun is not typically exposed than where it is.
Yeah, the title is a bit hokey, but the content is excellent…
… and while we’re on topic …
I was listening to a talk about cancer recently and the speaker said the same thing; don’t wear sunglasses. Her reasoning was the melanin in the eyes converts the light into energy. The eyes don’t have a blood supply so they use melanin and it means less damage for the eyes, not more. Probably something about mitochondrial health in that too.
According to Dr. Berry that would be correct. Something about sunglasses preventing the vit D receptors from turning on or being retarded. Sunlight in the eyes is supposed to stimulate the vit D to protect us.
I don’t know how much of that is true but I do know that after about six or eight months as a carnivore I lost my day blindness. I noticed that I didn’t need sunglasses when I went outside. I’ve always had to wear sunglasses outside regardless of the cloud cover. I couldn’t see when outside unless I squinted my eyes almost shut. When I was in the Army I had to get a prescription to wear sunglasses when in formation. In the other hand I had great night vision and was always pick for night patrols.
That’s interesting, as I spent years in Arizona (300+ totally sunny days a year), and just got used to wearing sunglasses. I’ll have to see what happens if I don’t wear sunglasses.
