Calcium and vitamin D supplements may not help prevent bone loss and fractures, according to a new study released Tuesday in the Journal of the American Medical Association. 

“Many consumers, especially older people who are concerned about bone loss, buy and take calcium and vitamin D pills expecting them to strengthen their bones and prevent fractures," says Consumer Reports' chief medical adviser Marvin M. Lipman, M.D.

Indeed, Americans spent close to $2 billion on the two popular supplements in 2016 alone, according to projected data from the Nutrition Business Journal.

But the new research suggests that the pills may not be worth the money.

Scientists in the Departments of Orthopaedic Surgery at Tianjin Hospital and Hebei Province Cangzhou Hosptial of Integrated Traditional and Western Medicine in China analyzed data from 33 studies involving a total of more than 50,000 adults over age 50 living in different countries.

All of the studies compared the fracture risk of people who took supplements containing calcium, vitamin D, or both to those who took a placebo or nothing at all.

"Supplements were not associated with less risk for new fractures, regardless of the dose, the sex of the patient, their fracture history, calcium intake in their diet, or baseline vitamin D blood concentrations," the researchers concluded.

What Past Research Shows

These new findings affirm previous research, such as a 2015 review of 59 randomized controlled trials, published in 2015 in the British Medical Journal. That data showed that taking daily calcium pills can increase bone density in people over 50 years old by 1 to 2 percent—not enough to prevent fractures. 

More on Supplements

“That small gain is not worth the risks, including an increased likelihood of heart disease, kidney stones, and gastrointestinal problems,” Lipman says.

Another study of 159 postmenopausal women published in the Journal of Clinical Endocrinology & Metabolism in 2013 found that markers that may indicate osteoporosis declined significantly for people who took calcium supplements, but were unchanged for those who took only vitamin D.

However, there is research that  shows vitamin D might possibly reduce the risk of falls in older people, which could help prevent fractures, according to the 2012 recommendations from the independent U.S. Preventive Services Task Force. It’s not clear exactly how vitamin D might prevent falls, although having very low levels of vitamin D has been linked with muscle weakness, so there is a theory that boosting levels back up may restore muscle strength.

“The key is developing strong bones early in life—before age 30 when our bones naturally start to thin,” Lipman says. “After 30, it’s a matter of preserving bone strength by consuming enough calcium in your daily diet so that the body doesn’t take what it needs from the bones."

The Council for Responsible Nutrition (CRN), the trade group for dietary supplements, suggests that this new research be weighed in conjunction with advice from your doctor.

"If there is the possibility of reducing the risk of a devastating fracture by supplementing with calcium and vitamin D, as some research has found, people should not be dissuaded from supplementation by a meta-analysis that is meant as a general recommendation, and may not apply to each individual," says Andrea Wong, Ph.D., CRN vice president, scientific & regulatory affairs.

How To Protect Your Bones

All of this is not to say that calcium and vitamin D don't have value. Adults need at least 1,000 mg of calcium and 800 IU of vitamin D daily. But the best way to get these nutrients is through food. Dairy products such as cheese, milk, and yogurt are rich sources, says Lipman.

Broccoli, collard greens, kale, canned salmon and sardines (eaten with the soft bones), and white beans are non-dairy sources.  (People who don't eat dairy should talk to their doctor about how best to get these nutrients.) 

Good sources of vitamin D are mushrooms, eggs, fortified milk, soy beverages, and salmon. Our bodies also make vitamin D when our skin is exposed to sunlight, so experts suggest getting 10 minutes of sunshine per day. 

Exercise is important, too.

“Weight-bearing aerobic activities, such as walking and dancing, may slow bone loss. Aim for 30 minutes each day, even if it’s just a brisk walk,” says Lipman.

And don't forget strength training. Not only does it help strengthen bones, it also builds muscle, which can help prevent falls.