A clear understanding of how much calcium you are already getting through your diet should precede supplement use.
By Diane L. Schneider, MD
Many women have questions about calcium supplements. Should you be taking a daily supplement? The answer is yes, no, or maybe, depending on what you are eating and what other supplements you are taking.
Jeanne, age 62, was trying to lower her risk of osteoporosis, which debilitated her mother, by taking calcium supplements and getting regular exercise. She sought my advice about prevention of osteoporosis. I instructed her to write down everything she ate and drank for three days and bring in all the vitamins and supplements she was taking so I could examine them.
On review of her diet, I noted that Jeanne was consuming 700 milligrams (mg) of calcium per day from various foods and drinks. She took a 600 mg calcium supplement twice a day. Her once-a-day multivitamin contained 500 mg of calcium. Altogether her diet and supplements totaled 2,400 mg of calcium.
For women over age 50 and men over age 70, the latest recommendation from the Institute of Medicine is 1,200 mg of calcium per day from all sources. At 2,400 mg per day, Jeanne was taking double what she needed, which could have a negative impact on her health. Excess calcium ends up in the urine, increasing the risk of kidney stones.
In addition, recent research suggests that a daily calcium intake of more than 2,000 mg may increase the risk of heart attacks, though it should be noted that studies on the subject of calcium supplements and cardiovascular risks for angina, heart attacks, strokes, and sudden death are inconclusive. Some studies found no association between calcium intake and cardiovascular problems, whereas others did find an association. The studies showing an association with heart attacks raises the possibility that excess calcium intake may increase cardiovascular risks. Therefore the Institute of Medicine in 2010 lowered its daily calcium recommendations for men and women over 50 to 1,200 mg and set the upper limit at 2,000 mg.
In Jeanne’s case, her primary care provider had recommended she take a supplement without obtaining a dietary history or asking what else she was taking. With an average of 700 mg in her diet and 500 mg more from her multivitamin, Jeanne already met the 1,200 mg recommended target. Taking the separate calcium supplement put her way over what she needed. She did not need a calcium supplement at all.
Jeanne’s case illustrates the importance of examining your current diet and supplement use to learn how much calcium you are already getting and establish the correct dosage. The following are some additional tips to help you understand calcium supplementation.
- Be aware of supplement serving size. If the serving size is three tablets and you are only taking one, you are getting only one-third of the amounts listed.
- Be dynamic in your supplement use and dose. Don’t take the supplement each day unless you are eating and drinking the same food items every day. For instance, you may have yogurt every morning for breakfast except on Saturday, when you have eggs. You won’t need to take a calcium supplement if you are getting a similar amount of calcium in your food (in this case, yogurt). On Saturday, when your breakfast has no calcium source, add one—such as cheese on your eggs—or drink fortified orange juice, almond milk, or a latte; or you can take a calcium supplement on that morning.
- You are probably taking too much calcium already. If you are just taking a 1,000 or 1,200 mg calcium supplement every day, you are probably getting too much. Even if you don’t consume dairy products, the average American adult consumes 300 to 400 mg of calcium from food each day. That means you don’t need more than 800 mg of calcium supplements, divided into two daily doses.
The final word: Take some time to figure your calcium intake. It is important to consume the right amount but not too much. Don’t forget about vitamin D too. Sufficient vitamin D is necessary for the absorption of calcium in the small intestine.
Diane L. Schneider, MD, is a geriatrician, epidemiologist, author, and co-founder of 4BoneHealth.org. An experienced writer and public speaker, Dr. Schneider is frequently featured as an osteoporosis expert on television and radio shows and in online articles, magazines, newspapers, and medical publications. Dr. Schneider is author of The Complete Book of Bone Health (Prometheus Books, 2011; $21).