Vitamin D is a fat-soluble nutrient that is produced by the body through skin exposure to sunlight, which triggers vitamin D synthesis. The body must have vitamin D to absorb calcium and promote bone growth. Vitamin D is also important for other body functions, including muscle, immune, colon, and breast health.* Unfortunately, despite the significance of the sun to vitamin D synthesis, many experts agree it is wise to limit sun exposure to the skin, which often results in lower-than-ideal Vitamin D levels in the body. Additionally, as we age, the body's ability to produce vitamin D diminishes. Vitamin D supplements are an excellent choice in helping to replenish and maintain adequate vitamin D levels in the body. Bronson's USDA Certified Organic Vitamin D3 delivers 10,000 I.U. in each tablet. And Bronson utilizes vitamin D3, the preferred form of this important nutrient. Research has demonstrated that Vitamin D supports bone, muscle, immune, colon, and breast health.*