Solgar - Vitamin D3 Cholecalciferol 5000 IU - 100 Softgels Solgar Vitamin D is a fat-soluble vitamin that is required to promote calcium absorption which helps to maintain healthy bones and teeth. Vitamin D also supports a healthy immune system and the health of various tissues such as those of the breast and colon. It may support neuromuscular function in older adults as well as the health of the pancreas.