D014807. Legal status. In Wikidata. Vitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and for many other biological effects. [1] [2] [3] In humans, the most important compounds in this group are vitamin D 3 ( cholecalciferol) and vitamin D 2 ( ergocalciferol ). Cholecalciferol (vitamin D 3) is in a class of medications called vitamin D analogs. Cholecalciferol is needed by the body for healthy bones, muscles, nerves, and to support the immune system. It works by helping the body to use more of the calcium found in foods or supplements. 2) Skin. Your skin is your largest organ and vitamin D is critical to its health. The active form of Vitamin D (calcitriol) helps with skin repair and growth. Vitamin D3 is the precursor to Calcitriol. As you get older your body loses the ability to produce D3 which leads to a weaker immune system and weaker skin. Immune cells, including dendritic cells, macrophages, and T and B cells, express the vitamin D receptor and 1α-hydroxylase. In vitro studies have shown that 1,25-dihydroxyvitamin D, the active form of vitamin D, has an anti-inflammatory effect. Recent epidemiological evidence has indicated a significant association between vitamin D deficiency In this comprehensive review, you'll discover: Which calcium supplements failed our quality ratings and which passed -- including combinations with magnesium,vitamins D & K, and boron. CL's Top Picks for calcium supplements. Cost comparisons to help you choose a calcium supplement offering the best value based on amounts of elemental calcium. Buy Calcium and Vitamin D Supplement - 180 Tablets - High Strength 1000mg Calcium Complex with Vitamin D3 Plus, Magnesium, Zinc and Vitamin C - Supports Bones, Cartilage and Muscle - Osteo Supplements on Amazon.com FREE SHIPPING on qualified orders Take calcium carbonate with food. The acid the stomach makes while eating helps the body absorb calcium carbonate. Total daily dose. It's best to take calcium in smaller doses. Smaller doses most often means 500 milligrams or less at a time. To take 1,000 mg of calcium a day, split it into two or more doses over the day. Other medicines. When taken together, vitamin C, vitamin D3, and zinc are a potent combination for delivering many health benefits, including immune support: Neuro-C Liposomal Vitamin C – advanced brain and immune defense. Vitamin D3 5000 – highly-potent and pure vitamin D3. Neuro Zinc – a mineral vital for health and survival. zRRSd.