Geri-Care oyster shell calcium plus vitamin D tablets are an excellent nutritional supplement for maintaining strong bones and a healthy body. Along with 500 milligrams of oyster shell calcium each tablet includes 200 IU of vitamin D-3 which helps with the timely and efficient absorption of calcium. Because the calcium comes from oyster shells it typically is easier for your body to absorb than other calcium methods. With continuous use this oyster shell calcium supplement may help to decrease the chances of serious diseases such as osteoporosis or rickets improve the strength of your teeth and bones and support your muscles and heart in the long run. It also may be helpful for low thyroid function bone-strengthening to counteract the effects of certain medications and even pregnancy support.