As humans have moved away from the equator, our skin has become less pigmented and allows for more of the Sun’s rays to produce Vitamin D in Â adequate quantites (actually Vitamin D is not a vitamin, it’s a pre-hormone substrate made from cholestorol in your blood and cells that goes on to provide one of the most important substances for hundreds of related processes).
But with clothing, suncreen and lots of indoor activity, humans in the northern hemisphere especially DON’T get enough Vitamin D which leads to rickets, colds, flu, colon cancer, breast cancer, non-Hodgkinâ€™s lymphoma, multiple sclerosis, type 1 diabetes, immune deficiency, cardiovascular diseases (e.g., hypertension, heart failure, sudden cardiac death), osteoperosis and myriad other diseases.
BUT WHY? It all goes back 400 million years ago when sea creatures first migrated onto land. In order to exist out of the water, calcification (for bone development and hundreds of other processes) needed to continue, but without the calcium (readily available in seawater) evolution required another mechanism to provide it. Sunlight and cholesterol build pre-hormone substrates that enable proper califerous processes to occur.
73% of people in the US are not getting the required levels of sunlight, especially in the winter, but you can do something about it. Get more sun, eat more foods containing vitamin D or take a supplement and you could STAVE OFF THIS YEARS FLU!