The Big Vitamin D Mistake (2017)
This summer I spent about six weeks making an effort to get as much sun exposure as I realistically could. I'd do 20-30 minute dog walks in the afternoon in shorts and no shirt, plus a few bike rides per week, also shirtless. I didn't take any vitamin D supplements and, as far as I know, wasn't eating any food with added vitamin D like milk.<p>At the end of it I did one of those mail-in vitamin D tests, and it put me at 40 ng/mL. Depending on the source, that's very bottom edge of the acceptable range.<p>Walking around with your shirt off feels pretty weird, and I can't imagine most people would even be willing to do that. And of course it's getting into the rainy season here in the pacific northwest, so there's no sun exposure to be had no matter what you do.<p>Seems like, at least for someone like me who works indoors, supplementing is the only option to stay within a healthy range. I figure humans are just not adapted to wearing a lot of clothing and staying indoors all the time. I'm now taking 5000 IU per day, and I plan to take another test in a few months. Subjectively I can say that I feel far better than I did a few months ago, but that could be placebo or due to other factors. Still, I'm pretty convinced I should be supplementing vitamin D.