Ostelin Calcium & Vitamin D3 Chewable comes in a convenient format with a pleasant citrus flavour. Calcium supports bone strength and bone density. A diet deficient in Calcium can lead to osteoporosis in later life. Calcium may help prevent Osteoporosis when dietary intake is inadequate. Calcium assists healthy bone development in teenagers. Vitamin D3 is a key nutrient as it helps increase calcium absorption. Vitamin D3 maintains muscle function and healthy immune system function.