I read and have heard on numerous radio and television programs about how the majority of people are vitamin D deficient. Lack of vitamin D can cause or worsen a variety of problems that most people don't realize. If you feel tired all the time or seem to be very moody, lack of vitamin D can be the culprit. This is even more common in states and countries that get a lot of rain, snow or less amounts of sunshine. Getting some sunshine is the natural way to get your vitamin D but is not always enough. Some people who experience chronic pain are not getting enough D in their life. I take one capsule daily to offset what I do not receive on a daily basis. I can always tell if I have skipped more than three days (which I don't make a habit). I feel like I have less energy and I feel aches in my feet. Whenever I hear friends and family complain of always being tired and having aches I tell them to be sure they are getting enough vitamin D. Dwayne is the one who started the whole thing and I am glad I listened. It truly has improved my quality of life and our whole family takes a supplement daily.