Vitamin D supplementation is reasonable. Strolling in daylight is even cheaper. I’ve been doing extra of each for the reason that beginnings of the pandemic. Slusky and Zekhauser add to the proof:
Daylight, doubtless working via the well-established channel of manufacturing vitamin D, has the potential to play a big function in decreasing flu incidence. A latest meta-analysis of 25 randomized managed trials of vitamin D supplementation (Martineau et al. 2017) demonstrated vital advantages of such dietary supplements for decreasing the probability that a person will contract an acute higher respiratory an infection. The present examine considers daylight as an alternate, pure path via which people can and do safe vitamin D. This examine’s findings complement and reinforce the Martineau et al. findings.
Our main result’s that incremental daylight within the late summer time and early fall has the potential to scale back the incidence of influenza. Daylight had a dramatic impact in 2009, when daylight was effectively under common on the nationwide degree, and the flu got here early. Our result’s doubtlessly related not simply to the present COVID-19 pandemic, but in addition to a future outlier H1N1 pandemic. The menace is there; some H1N1 viruses exist already in animals (Solar et al. 2020). One should be cautious, although, with generalizations, given the distinctive financial circumstances (e.g., a 25-year excessive unemployment price) within the fall of 2009.
A remaining query is whether or not daylight issues extra broadly for flu, or whether or not it’s distinctive to H1N1. Whereas we lack a counterfactual of an early flu from a special pressure, we do have two items of proof to recommend that the impact is broader than simply H1N1. First, as described all through the paper, the Martineau et al. examine concerning the relationship between Vitamin D and higher respiratory infections aren’t particular to H1N1. Second, with granular, county degree information, we do see strongly statistically vital damaging results of fall daylight on influenza for years apart from 2009 (see Columns (2) and (3) of Panel of Desk 7). Subsequently, aside from its methodological contributions, this examine reinforces the long-held assertion that vitamin D protects in opposition to acute higher respiratory infections. One can safe vitamin D via dietary supplements, or via a stroll open air, significantly on a day when the solar shines brightly. When most stroll, herd safety gives profit to all.
The Scots are giving out free vitamin D to folks caught indoors. My view is that Vitamin D supplementation is worth it however the place and when potential the daylight strategy is healthier because the impact may go via mechanisms past vitamin D.
Hat tip: The sunny Kevin Lewis.