Vitamin D has gotten a lot of attention over the past decade, and for good reason. This fat-soluble vitamin is made by our bodies and can be eaten or taken as a supplement. Like all other vitamins, it is no magical cure-all, but it does play a vital role in our overall health and functioning. Like flavonoids and vitamin A, vitamin D can and does influence the activity of our DNA, turning genes on and off by binding to receptors on the outer layer of our cells.