As I get older I find myself taking more and more supplements. The blood tests I have to take every three months always point out any deficiencies that I may have and fortunately there are ways to supplement those vitamins and/or minerals. As you age you typically spend less time in the sun, you may suffer from dairy allergies, and you may try to eat healthier by becoming more vegan. Any or all of these habits can result in Vitamin D deficiency. After all, Vitamin D is the sunshine vitamin, produced by the body in response to your skin being exposed to sunlight. It also occurs naturally in a few foods and in fortified dairy and grain products. Vitamin D is essential for strong bones because it helps the body use calcium from your diet. Bone pain and muscle weakness can indicate a Vitamin D deficiency. It can also increase the risk of Cardiovascular disease, cognitive impairment in older adults, severe asthma in children, and various forms of cancer. None of those are conditions that anyone wants to have to deal with. Now that I'm closing in on age 69 the use of proper supplements has become even more important to me. Just recently I had surgery to remove a cyst from my spine. The surgery went well and I felt better immediately. However six weeks after the surgery I tripped on the cord to one of our exercise machines and fell on my left hip. The pain was severe, the bruising extensive, and my surgical recovery was set back a few months. However broken hips in older people can actually be life threatening if weak bones are involved. Fortunately my Vitamin D level was high enough to avoid an extensive fracture. So I am a big proponent of Vit D from experience. We used to belong to Life Extension's Premier Rewards Program but discovered that Amazon often offers the same vitamins we have been buying through LE at the same prices or even lower -- especially when considering the $50.00 program annual fee at Life Extension. If you're trying to treat your body well, buy the best! It will pay off in spades