Vitamin D

Theories around our deficiency of it out here in the cloudy, chilly, drizzly Pacific Northwest: Connections are being made between lack of sunshine and resulting D deficiency contributing to several bad things, such as MS, cancer, depression, etc. So we roll up our sleeves and avoid sunscreen early in spring, at least for about ten or fifteeen minutes.
Carter's Wise children is wittily crazily fun.