My husband has stage 4 esophageal cancer. He has been taking Coral Calcium (like advertised on TV) for 2 weeks. He has much more energy, feels and looks great and I believe it is helping to shrink his inoperable tumor. We'll know soon as he stopped all chemo to do nutrition and supplements 100%. I buy it at Walgreen's for $20 a bottle of 90 gel caps. Just make sure whatever you buy has Magnesium and Vit. D in it so your body can absorb it. Good Luck! Judy T.