Vitamin C contributes to normal collagen formation for the normal function of bones, cartilage, skin and teeth. Calcium and magnesium are needed for the normal maintenance of bones and teeth. Vitamin D contributes to normal blood calcium levels and to the normal absorption / utilisation of calcium. Vitamin D also helps maintain normal bones, teeth and muscle function.Vitamin K contributes to the maintenance of normal bones. The vitamin C in this formula is buffered to be gentle on the stomach. The calcium and magnesium are cheltated as citrates. Additional boron and malic acid. Vitamin D in this formula is vegan. Ingredients:INGREDIENTS: four vegetarian capsules provide: Calcium (citrate) 260mg Magnesium (citrate) 260mg Vitamin C (ascorbic acid) 60mg Vitamin K 50ug Malic Acid 40mg Boron (sodium borate) 1200ug Vitamin D2 (ergocalciferol) 10ug Directions:As a food supplement, take four capsules daily with food, or as directed by your healthcare practitioner.