Nutrients and Vitamins: Calcium

Calcium is one of the most important mineral nutrients the human body needs to function properly. It is required for muscle contraction, blood vessel expansion and contraction, secretion of hormones and enzymes, and transmitting impulses throughout the nervous system. It is also important for maintaining strong bones and teeth. Recommended intake of calcium varies by age, sex and health conditions but, for most adults, between 1,000 and 1,500 milligrams per day is more than sufficient.

As is the case with all nutrients required by the body, the best sources for calcium come from foods containing them. The best sources are milk, yogurt, and cheese – preferably the low-fat brands. Nondairy sources include vegetables, such as Chinese cabbage, kale, and broccoli. Foods fortified with calcium include many fruit juices and drinks, tofu, and most cereals. 1 cup of milk contains ∼300 mg of calcium, 1 oz of cheese ∼245 mg and 1/2 cup of tofu is ∼250 mg. A great rule of thumb is if you did not consume 3 servings of dairy or calcium rich foods a day, consider supplementing.

When choosing a calcium supplement, look for calcium citrate, as it is more easily absorbed than calcium carbonate. Calcium should be taken in small doses throughout the day, as the body can only absorb small amounts at one time. For example, your body absorbs more calcium if you take one 250 milligram tablet twice a day rather than one 500 milligram tablet once a day. If a higher dose calcium tablet is a better buy, break it in half.

Calcium is also available in liquid form if pills are a concern. Before taking any supplement, however, check with your doctor to make sure it’s right for you and won’t adversely interact with any medicines you might already be taking. Several epidemiological studies have found an association between calcium intakes and an increased risk of developing prostate cancer; however, more research on this is needed. In addition, several studies performed on laboratory animals found a possible connection between too much calcium and inhibited vascular function. More study is needed on this as well, before a definitive conclusion can be drawn.

Interested in a podcast? Check out Maximum Wellness, Episode 46: Immune Update: How Your Defense Fights & Nutrients That Support It