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A new paper that has not been peer-reviewed (yet – link below) suggests a link between Vitamin D and COVID-19. Vitamin D helps to boost the immune system.
So, it would be safe to say that opening beaches and recreation areas would naturally improve people’s immune system because they get out into direct sunlight. Another reason there are fewer cases of flu during the summer months. Human skin naturally produces Vitamin D when exposed to direct sunlight. It is worth noting that as our skin ages it produces smaller amounts of Vitamin D in direct sunlight.
Another bizarre fact is that more than 25% of the U.S. population never goes outside. This probably happens mostly in big metropolitan areas like NYC and NJ. Coincidently, almost half of the deaths from COVID-19 have occurred in this area.
So, get out there and show some skin.