Sunlight through glass does not provide Vitamin D

Re:Sunlight through glass does not provide Vitamin D by wongarsu on Monday February 25, 2019 @12:12PM (#19247212)

There's another important factor to consider, and that's how we expose ourselves to UV. Our ancestors used to be outside most of the day, allowing skin pigmentation to adapt to the regional and seasonal UV levels. Until agriculture came along fairly recently we also lived mostly in the shade of the forest and not in direct sunlight.

Compare that to today, where UV exposure mostly means exposing the skin to massive bursts of UV for short times, at best in an effort to build skin pigmentation that isn't sufficient. That's completely different and much more damaging, leading to the general feeling that any UV is bad.

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Re:Sunlight through glass does not provide Vitamin D by jeffdavis on Monday February 25, 2019 @02:10PM (#19248414)

We are also a lot cleaner. We remove dirt and dead skin, whereas our ancestors left it there and it may have acted as a protective shield from UV.

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Re:Sunlight through glass does not provide Vitamin D by rossdavidh on Monday February 25, 2019 @08:26PM (#19251251)

I think our ancestors lived in the full sun of the African savannah a lot more than the forest, and even in northern Europe, hunter gatherers were killing meat-on-the-hoof (mammoth, wild horse, etc.) so they were running about in the open a lot.

However, the change in exposure is surely true. I'm just not at all convinced that complete shielding from UV is a better choice than occasional UV.

Until recently, children would run around outside a lot during the summer, even in urban environments, and especially in suburban or rural ones.

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