Latitude matters. The farther north you are the more time in the sun you’d need. In some far north places, the sun you do get is not strong enough to get any Vi

Latitude matters. The farther north you are the more time in the sun you’d need. In some far north places, the sun you do get is not strong enough to get any Vit D. https://jaoa.org/article.aspx?articleid=2635300 https://jaoa.org/article.aspx?articleid=2635300 https://www.grassrootshealth.net/document/sunshine-calendar/ https://www.grassrootshealth.net/document/sunshine-calendar/