DEAR DR. ROACH: Which type of calcium supplement is best absorbed? How many milligrams do you suggest for a woman in her 60s? — D.R.
ANSWER: Most calcium supplements sold are either calcium carbonate or calcium citrate, and either one is reasonable in people who need calcium supplementation. I prefer dietary calcium when possible: Calcium supplements increase the risk of kidney stones, while calcium in food (dairy products and fish with tiny bones, such as sardines, are excellent sources) decreases kidney stone risk.
Further, there is some suggestion that calcium supplementation may increase heart disease risk, and while the evidence is conflicting, calcium from food seems safer than calcium supplements to me.
The standard recommendation is 1,200 mg of elemental calcium a day from a combination of food and supplements for a woman over 50 or a man over 70. (Read labels carefully: A 1,250 mg serving, which may be one or more tablets of calcium carbonate, contains 500 mg of elemental calcium.)
Calcium carbonate is best absorbed with food, while calcium citrate is well absorbed with or without food. Calcium carbonate is not well-absorbed by people taking proton pump inhibitor medicines like omeprazole (Prilosec).
