Vitamin D is required to promote calcium absorption, which helps you maintain healthy bones and teeth and supports a healthy immune system. But your body produces this essential nutrient less efficiently as you age, and if your body doesn't absorb calcium properly, your bodily systems that need it will take it from your bones, where it's essential, as well. The Superior Source Extra-Strength supplement provides you with 5,000 international units (IU's) of Vitamin D3 in the same form that your body produces when your skin is exposed to sunlight. It can help you maintain strong bones and teeth, healthy immune function, and breast, colon and pancreas health - in just one instant-dissolve MicroLingual tablet!