Calcium is the body’s most abundant mineral, and it’s essential for the development and strengthening of bones and teeth, muscle contraction and relaxation, and blood clotting, says Melissa Prest, D.C.N., R.D.N., a spokesperson for the Academy of Nutrition and Dietetics. It’s recommended that adults under 70 consume 1,000 milligrams (mg) daily, according to the National Institutes of Health (NIH), which is best achieved through diet in foods like milk, cheese, and yogurt, and non-dairy alternatives like kale, broccoli, and fortified juices and tofu. If you eat dairy-free, though, or have been diagnosed with a deficiency by your doctor, then taking a calcium supplement may be a good idea.
“There are many health conditions that may predispose someone to have a calcium deficiency,” Prest says. Some of those include eating disorders, mercury exposure, lack of parathyroid hormone, kidney failure, celiac disease, Crohn’s disease, inflammatory bowel disease, vitamin D deficiency, and prolonged use of laxatives or chemotherapy drugs. “People who eat high amounts of protein or sodium may also need to supplement calcium because a high intake of either increases calcium excretion,” she adds.
Supplements contain different types of calcium—most commonly calcium carbonate and calcium citrate. Calcium carbonate has to be taken with food, as it relies on stomach acid to absorb and can otherwise cause nausea and bloating. Calcium citrate, on the other hand, is more easily absorbed and doesn’t require food to take.
How we chose the best calcium supplements
We gathered expert input from Melissa Prest, D.C.N., R.D.N. and Caroline West Passerrello, M.S., R.D.N., L.D.N., both of whom are spokespeople for the Academy of Nutrition and Dietetics, and relied on the registries of supplements vetted by the United States Pharmacopeial Convention (USP) and the National Sanitation Foundation (NSF).
Our top picks
Keep scrolling for the best calcium supplements that are third-party tested, USP-certified, or NSF-certified.