When you were a child, your mom may have encouraged you to drink milk to build strong bones. But as an adult, you’re much more likely to take a calcium supplement than down four glasses of milk a day to protect your bone health. However you do it, getting enough calcium is a good idea, since women are far more likely than men to develop osteoporosis — a condition of weak and fragile bones that makes you prone to fractures: Of the 10 million Americans with osteoporosis, 80 percent are women.

But before you unwrap that chocolate-flavored calcium chew or swallow a calcium pill, you should know that taking calcium supplements may not be helping your bones at all. Even worse? The supplements may lead to major health problems

The Best Calcium Supplement Is None

It’s important to protect your bone strength and guard against fractures as you age, but taking a supplement isn’t the best way to do that, says Erin Michos, MD, MHS , associate director of preventive cardiology for the Ciccarone Center for the Prevention of Heart Disease . “A nutrient in pill form is not processed in the body the same way as it is when ingested from a food source. Furthermore, people believe that the proof that calcium supplements fortify bones is more robust than it really is,” she says. “The truth is, the research is inconclusive. But there is a growing body of evidence that suggests no health benefit, or even worse, that calcium supplements may be harmful.”

Multiple studies have found that there’s little to no benefit to taking calcium supplements for the prevention of hip fractures. On the other hand, recent studies have linked calcium supplements with an increased risk of colon polyps (small growths in the large intestine that can become cancerous) and kidney stones, which are hard masses usually formed in the kidneys from an accumulation of calcium and other substances. Additionally, a 2016 study by Michos and her colleagues suggested that calcium supplements may increase the risk of calcium buildup in the heart’s arteries.

“I’m very concerned about the potential for calcium supplements to contribute to heart attacks and heart disease,” says Michos. “The body can’t process more than 500 milligrams of calcium at a time. If you take a supplement with more than that, your body has to do something with the excess. It’s possible that higher calcium levels in the blood could trigger blood clots or that calcium could be deposited along artery walls, which would contribute to the narrowing of blood vessels.” 

A Better Calcium Option

While taking calcium supplements may produce unwanted side effects, meeting your calcium needs through your diet is safe. “When you get calcium through your diet, you’re taking it in small amounts spread throughout the day along with other food sources, which helps you absorb the nutrient,” explains Michos. “Most people can get adequate calcium through their diet if they make an effort.”

Women ages 19 to 50 should consume 1,000 milligrams of calcium a day, and the target for women over 50 is 1,200 milligrams per day. Good dietary sources of calcium include:

• Almonds
• Oranges
• Dried figs
• Soybeans
• Garbanzo, white and pinto beans
• Low-fat dairy such as milk and yogurt
• Leafy green vegetables such as kale and spinach

Exercise to Strengthen Bones

Being active and exercising on a regular basis protects bone health. Weight-bearing exercises such as walking, jogging and weight training are especially helpful in preventing bone loss.

Simply moving more throughout the day supports bone health, too. Research indicates that women who sit for more than nine hours a day are 50 percent more likely to have a hip fracture than those who are less sedentary. Finding ways to work more walking or standing into your day can add up. For example, park farther away from buildings, take the stairs instead of the elevator and pace while on phone calls.

For most women, skipping calcium supplements in favor of boosting dietary calcium and focusing on weight-bearing exercise is the best way to keep bones strong. But if you’re still concerned about getting enough calcium, talk to your doctor first before taking supplements to see if you really need them.