Science-Based Nutrition Plant Sourced Vitamin D3 Dietary Supplement Vegan Non-GMO - Gluten Free - Soy Free Helps Regulate Calcium and Phosphorus Levels Needed for Healthy Bones and Teeth Helps Support Immune and Heart Health Doctor's Best Vegan D3 features Vitashine D3 (as cholecalciferol), needed for the body to regulate phosphorus and calcium levels for healthy bones, teeth and heart protection. Vitamin D3 is produced in the skin by absorbing the sun's UV rays and is obtained from food in limited amounts, Sun protection and climate factors may influence low Vitamin D3 levels. Vitamin D3 is beneficial for immune, cardiovascular, bone density and structure, and cellular function. It plays a role in most organs and systems of the body and influences the chemical messengers of the immune system.