Mass Vitamin D Caps are a high quality and effective source of vitamin D. Each Mass Vitamin D tablet contains 7.5μg vitamin D. Vitamin D enters the body after the skin is exposed to sunlight. When there is limited sunlight i.e. winter or in the Nordic countries where there are very long periods of darkness, we recommend taking vitamin D as a supplement. Vitamin D promotes the absorption of calcium and phosphorus, as well as to maintaining normal levels of calcium in the blood. Vitamin D is also important for the well-being and strengthening of bones, normal muscle activity, as well as the normal functioning of the immune system.