A year and a half ago, the father of a friend of mine started taking Vitamin D3, 5000 IU/day at around 7 am — soon after getting up. That his regimen is exactly what I’d recommend (good dose, good time of day) is a coincidence — he doesn’t read this blog. He used to get 3 or 4 terrible colds every year, year after year. Since he started the Vitamin D3, he hasn’t gotten any. “A huge lifestyle improvement,” said my friend. His dad studied engineering at Caltech and is a considerable skeptic about new this and that.
Much more recently his mother changed the time of day she took her usual dose of Vitamin D3. For years she had been taking half in the morning (with a calcium supplement) and half at night. Two weeks ago she started taking the whole dose in the morning. Immediately — the first night — her sleep improved. She used to wake up every 2 hours. Since taking the Vitamin D3 in the morning, she has been waking up only every 3-6 hours. A few days ago, my friend reports she had “her best sleep in years”.
Sleep and immune function are linked in many ways beyond the fact that we sleep more when we’re sick. A molecule that promotes sleep turned out to be very close to a molecule that produces fever, for example. I found that when I did two things to improve my sleep (more standing, more morning light) I stopped getting colds. So it makes sense that a treatment that improves one (sleep or immune function) would also improve the other (immune function or sleep).
A few days ago I posted a link about a recent Vitamin D study that found no effect of Vitamin D on colds. The study completely neglected importance of time of day by giving one large injection of Vitamin D (100,000 IU) per month at unspecified time. I commented: “One more Vitamin D experiment that failed to have subjects take the Vitamin D early in the morning — the time it appears most likely to have a good effect.” These two stories, which I learned about after that post, support my comment. What’s interesting is that the researchers who do Vitamin D studies keep failing to take time of day into account and keep failing to find an effect and keep failing to figure out why. I have gathered 23 anecdotes that suggest that their studies are failing because they are failing to make sure their subjects take their Vitamin D early in the morning. Yet these researchers, if they resemble most medical researchers, disparage anecdotes. (Disparagement of anecdotes reaches its apotheosis in “evidence-based medicine”.) The same anecdotes that, I believe, contain the information they need to do a successful Vitamin D clinical trial. Could there be a serious problem with how Vitamin D researchers are trained to do research? A better approach would be to study anecdotes to get ideas about causation and then test those ideas. This isn’t complicated or hard to understand, but I haven’t heard of it being taught. If you understand this method, you treasure anecdotes rather than dismiss them (“anecdotal evidence”).