The Physiology of COVID and Colds

Melatonin is a hormone that is controlled by lightness and darkness physically. And it seemingly happens the most in places where the sun, the shift in sunlight is like dressed in more northern parts of the U.S., Canada. There's also a direct correlation between vitamin D which is synthesize using the energy from sunlight and cholesterol in your body to make serotonin. When you're not seeing the sun, it increases and it makes you more fatigued. That can lead to isolation and these things that people are always more sad when they're isolated.