This article set off a lightbulb as a possible explanation for the prevalence of osteoporosis in older Asian women. If the mechanism is: unfiltered sunlight -

This article set off a lightbulb as a possible explanation for the prevalence of osteoporosis in older Asian women. If the mechanism is: unfiltered sunlight -> Vitamin D production -> increased calcium absorption -> decreased risk of osteoporosis; then in many Asian cultures, the desire for women to have fair skin, cover up as much as possible, use sunscreen judiciously, and even use umbrellas when going outside; would certainly cause a Vitamin D deficiency and increased risk of osteoporosis by old age. Has anyone measured if this is possible?