Calcium May Help Prevent Hormone Disorder
Calcium Supplements May Lower the Risk for Hyperparathyroidism
WebMD News Archive
Oct. 18, 2012 -- Women who supplemented their diets with modest amounts of calcium had a lower risk for the hormone disorder known as primary hyperparathyroidism.
The study, which is published in BMJ, also found that women with diets low in calcium may be more likely to get the disorder, which erodes bones and potentially sets the stage for depression, fatigue, and kidney stones. The research may be a reason to revisit the idea of taking a daily calcium supplement.
Many women shelved their calcium pills last year after an expert panel concluded they don’t prevent osteoporosis-related fractures, at least in postmenopausal women. Recent studies have also tied calcium supplements to a higher risk of heart attacks and strokes.
For example, a 2010 report on dietary calcium by the Institute of Medicine concluded that most healthy adults don’t need supplements because national surveys show average intakes are adequate.
"The problem is that the average is not exactly what everybody gets," says Bart L. Clarke, MD, an endocrinologist and associate professor of medicine at the Mayo Clinic in Rochester, Minn. "To take a supplement of about 500 milligrams a day, that amount makes up the difference, really, I think, for what most women’s diets might be missing."
"This makes perfect sense to me. As long as they’re not taking too much,” Clarke says.
The Institute of Medicine recommends that nearly all adults get 1,000-1,200 mg of calcium a day to meet their daily needs for strong bones.
Calcium Levels Linked to a Common Hormone Disorder
For the new study, researchers tracked more than 58,000 women taking part in the long-running Harvard Nurses’ Health Study. Every four years, the women were asked about their diets and overall health.
Over the 22 years of the study, 277 women were diagnosed with primary hyperparathyroidism.
In hyperparathyroidism, the parathyroid glands release excess hormones that pull more than the needed amount of calcium out of the bones and then deposit it into the blood.
Diets low in calcium may chronically stimulate the parathyroid glands, which normally work like thermostats. When calcium levels dip, they effectively "turn on" and pull calcium from bone. When there’s enough calcium coming in through food and other sources, they shut off. Their job is to keep calcium levels stable.
The high blood calcium caused by hyperparathyroidism can cause “trouble with the body’s electrical system so that people become tired, fatigued, depressed. They get bad osteoporosis. Calcium collects in their kidneys and causes kidney stones,” says James Norman, MD, chief of the Norman Parathyroid Center in Tampa, Fla., a center that specializes in surgery to remove parathyroid glands. Norman wrote an editorial on the study, but he was not involved in the research.
“It [hyperparathyroidism] often goes unrecognized because doctors aren’t used to looking for it,” Norman tells WebMD.
Hyperparathyroidism affects about 1 in 800 people, but it’s more common as we age and especially in postmenopausal women. “One in 250 women over age 55 will get a parathyroid tumor in her lifetime,” Norman says.