m4burns

For example, this 2019 NIH grant awarded to Ecohealth Alliance Inc.: https://reporter.nih.gov/project-details/9819304

This is part of a series of ongoing projects that have received NIH funding over the last 7 years. Ecohealth, in turn, funds WIV: https://www.nature.com/articles/d41586-020-02473-4

Good points. Here is some data on vitamin D deficiency in the UK (where the original study was conducted) that also addresses seasonality: https://www.bjfm.co.uk/prevention-of-vitamin-d-deficiency

"Low serum levels of vitamin D are found in significant numbers of all population groups in the UK: in winter 30-40% of all age groups in the general population are classed as vitamin D deficient. Even towards the end of summer 8% of adults and 13% of adolescents remain deficient."

where deficient is defined as < 25 nmol/L of 25(OH)D

This is close to the rate of vitamin D deficiency in the general population, e.g. https://www.ncbi.nlm.nih.gov/pubmed/21310306