Vitamin D and Calcium: Should Women Take Them?

Calcium and Vitamin D have been a mainstay of older women’s supplement intake for years. Physicians recommend a daily dose of the combo to reduce the risk of osteoporosis, a condition where bones become so weak that a fall or even a coughing fit can cause a break. Though osteoporosis can affect both men and women, postmenopausal women bear a higher risk.

Now, an analysis of years’ worth of data, published in the Annals of Internal Medicine, is shedding new light on how the calcium plus Vitamin D combo affects a woman’s odds of developing other diseases later in life. Using information from the landmark Women’s Health Initiative, a series of government-sponsored clinical studies launched in 1991, researchers found that taking calcium and vitamin D lowered a woman’s long-term of dying from cancer by 7%.

But it’s not all good news. The analysis also found that the daily combo supplementation can raise a woman’s risk of fatal heart disease by 6%. There’s an explanation for that.

Calcium supplements, says Violet Lagari-Libhaber, D.O., an endocrinologist with the University of Miami Health System, are believed to create calcification in the arteries, which, in turn, can raise the risk of cardiovascular disease.

“We also know that too much calcium increases the risk of kidney stones,” adds Dr. Lagari-Libhaber, who specializes in diseases of calcium metabolism, including osteoporosis. It can affect the brain and even weaken bones instead of strengthening them.  In addition, “too much vitamin D can be life-threatening.”

This doesn’t mean that older women should bypass — or drop — the daily combo supplement.

Postmenopausal women have a higher risk of developing osteoporosis because a drop in the hormone estrogen is linked to a loss in bone density. 

While the ideal way of getting calcium is through the foods we eat — think dairy, kale, spinach and broccoli — many people, particularly as they age, don’t absorb the recommended daily requirement through diet alone. Likewise, most of us don’t get enough vitamin D from sun exposure. Dr. Lagari-Libhaber points out that supplementation is usually the only way to ensure older women are getting the required amount of both nutrients.

Taking them together is essential for good bone health, as vitamin D helps in calcium absorption.  “We do know for sure that both [calcium and vitamin D] ensure proper bone mineralization,” she says.

She recommends that women talk to their physicians to determine if or when they should start supplementing and the proper dosage for them. This is especially important in the case of women who have been supplementing without a doctor’s advice.

“The takeaway from all this is that every person should have a conversation with their doctors about their personal risks,” Dr. Lagari-Libhar says.

“It has to be decided on a case-by-case basis. It’s very difficult to give a blanket recommendation.”

For the study, researchers examined the medical records of more than 36,000 postmenopausal women to address major health issues in postmenopausal women. For the analysis, researchers compared women taking 1,000 milligrams (mg) of calcium carbonate and 400 international units (IU) of vitamin D3 to women taking a placebo. Though the study ended in 2005, the participants were tracked through the end of 2020.

Study authors noted that the research shows an association — not a direct cause-and-effect link — between supplementation and increased or reduced mortality. They also emphasized that they don’t know what combination is most strongly associated with mortality, whether calcium alone, vitamin D alone, or a combination of the two.

Dr. Lagari-Libhar doesn’t think the findings will change dietary recommendations.  Currently, the National Institutes of Health recommends 1,200 mg of calcium and 600 international units of vitamin D for women older than 50. 

Ultimately, the new data clarifies and underscores the kind of behavior every patient should practice before popping any pill or drinking any dietary additive.

 “Supplementation of any kind,” she says, “needs to be under the supervision of a physician.”

Ana Veciana-Suarez is a regular contributor to the University of Miami Health System. She is an acclaimed author and journalist who has worked at The Miami Herald, The Miami News, and The Palm Beach Post. Visit her website at anavecianasuarez.com or follow her on Twitter: @AnaVeciana.

Tags: Bone health supplements, Calcium and heart disease risk, Dr. Violet Lagari-Libhaber, Osteoporosis prevention, Postmenopausal women’s health