Basic Pursuits

In much of the reading I've done about vitamin D, it has been stated that the best source of vitamin D is sunshine. The skin synthesizes sunlight and makes vitamin D.

But almost as a precaution, it's further stated that if you are old, you lose the ability to make D.

A recent study just published in the American Journal of Epidemiology suggests otherwise.

Those persons aged 60 or more years who participated in daily outdoor activities had a mean 25-hydroxyvitamin D concentration similar to that of persons aged 20–39 years: 77 versus 79 nmol/liter, respectively. These nationally representative data suggest that persons aged 60 or more years can synthesize enough vitamin D from daily outdoor activities to maintain vitamin D levels similar to those of young adults.

It's simply that older people must spend the same amount of time in the sun as younger people to produce the same amount of D.

Frequency of Leisure-Time Physical Activity and Serum 25-Hydroxyvitamin D Levels in the US Population: Results from the Third National Health and Nutrition Examination Survey