If You're Overdoing This Supplement, Your Heart Is at Risk, Doctors Say

A study shows there's danger that can come with this particular mineral.

Even if we don't always completely stick to it, most of us know that balance and moderation are key to a healthy diet, and that includes incorporating vitamins and minerals into our daily routine. However, it's also worth bearing in mind that it's possible to have too much of a good thing—and in the case of one mineral, that is particularly true. Research has shown that, in excess, calcium supplements have the potential to damage your heart. Keep reading to find out why less may be more in the case of calcium, and for another vitamin you may need to dial back, check out If You Take Too Much of This Vitamin, It Could Be Toxic, Experts Say.

Calcium is very important for a healthy body.

Happy elderly couple drinking milk and spending time together at home
tonefotografia / iStock

The National Institute of Arthritis and Musculoskeletal and Skin Diseases stresses the importance of calcium for your overall health. "Calcium is needed for our heart, muscles, and nerves to function properly and for blood to clot," they explain.

It's also key for bone health. Low calcium levels lead to low bone mass and high fracture rates. "Most people are not getting the calcium they need to grow and maintain healthy bones," the experts at the National Institute explain. "Inadequate calcium significantly contributes to the development of osteoporosis."

They advise that men aged 51 to 70 need 1,000 mg per day, while women require slightly more at 1,200 mg. Sex aside, anyone over 70, they say, should aim to get 1,200 mg per day. And for more on supplements, check out The One Vitamin You Should Never Take, Doctors Say.

Many people over a certain age tend to take calcium without speaking to a doctor.

Woman hand holds white medication pills, pours from a white bottle into palm the calcium tablets dietary supplement.

The National Osteoporosis Foundation warns that many people think the wrong way about bones and imagine them to be a hard, solid mass, rather than living, growing tissue that needs nutrition. Along with regular exercise and limiting smoking, they recommend getting enough calcium and vitamin D as "essential to building strong, dense bones when you're young and to keeping them strong and healthy as you age."

In response to this advice, many people take extra calcium supplements. Johns Hopkins Medicine estimates that "more than half of women over 60 take calcium supplements—many without the oversight of a physician—because they believe it will reduce their risk of osteoporosis." And for the signs you're lacking in certain vitamins and minerals, check out 20 Surprising Signs You Have a Vitamin Deficiency.

Research has shown that calcium taken as supplements can raise your risk of heart damage.

Woman taking a pill or a supplement

In a 2016 report published in the Journal of the American Heart Association, Johns Hopkins researchers analyzed 10 years of medical tests covering more than 2,700 patients to examine the causes of heart disease. They concluded that taking calcium in the form of supplements "may raise the risk of plaque buildup in arteries and heart damage."

However, the problem seemed specifically connected to consuming the mineral as an additional tablet as opposed to a naturally occurring element in food, as "a diet high in calcium-rich foods appears be protective." Good food sources of calcium include dairy produce, oily fish like sardines, and dark leafy greens.

"When it comes to using vitamin and mineral supplements, particularly calcium supplements being taken for bone health, many Americans think that more is always better," study co-author Erin Michos, MD, current director of Women's Cardiovascular Health at Johns Hopkins, said in a statement. "But our study adds to the body of evidence that excess calcium in the form of supplements may harm the heart and vascular system." And for more news on vitamins you could be deficient in, If Your Gums Tend to Bleed, You May Be Lacking This Vitamin, Study Says.

Your body processes calcium via supplements differently than via food.

Old style bottle of milk sitting on wood table shot from slightly above with selective focus.
hutch photography / Shutterstock

The researchers looked at the effects of calcium supplements on the heart and vascular system because of suggestions from previous research that when taken in this way, it didn't make it to the skeleton, but also wasn't fully expelled through urination, meaning that it was likely to be accumulating somewhere in the body's soft tissues.

"As a person ages, calcium-based plaque builds up in the body's main blood vessel, the aorta and other arteries, impeding blood flow and increasing the risk of heart attack," the experts at Johns Hopkins explain. While it remains to be seen why the body processes supplemental calcium in this way, theories include the presence of calcium salts in tablets, or simply that such a large concentrated dose can't be processed as it can when it's consumed via food.

Michos concludes that while "there doesn't seem to be any harm in eating a heart-healthy diet that includes calcium-rich foods … patients should really discuss any plan to take calcium supplements with their doctor to sort out a proper dosage–or whether they even need them." And for one source of calcium to steer clear of, check out If Your Milk Carton Doesn't Say This, the CDC Says Don't Drink It.

John Quinn
John Quinn is a London-based writer and editor who specializes in lifestyle topics. Read more
Filed Under