Popeye had it right. Eat spinach and grow big bones and muscles. Don't like that green leafy calcium-rich spinach? Hate dairy? Americans purchase calcium supplements to a tune of over $1.2 billion annually even as the Institute of Medicine reports that almost all Americans get adequate amounts of calcium in their regular diets. Still we buy.
A key component of bone health, there has been some concern that too much calcium in our bodies from a combination of diet and supplements may cause health problems.
Calcium supplements, what do you know? T or F?
1. Vitamin D enhances calcium absorption.
2. Calcium supplements contribute to cardiovascular disease.
3. Tums and Rolaids contain calcium carbonate.
Calcium is necessary for normal cell physiology, muscle and blood vessel contraction and maintenance and repair of bone. About 99 percent of calcium is stored in our bones and teeth. Children have tremendous rates of bone mass development which peaks about age 30. Thereafter, there is a small decline in bone mass every year. Calcium is often recommended to build strong bones and slow the net loss of bone mass as we age. But some of us take that advice a wee bit too far.
Heart disease is the number one killer of men and women. There has been concern that too much calcium may play a role in the development of cardiovascular and kidney disease. Excess calcium can be deposited in cells including the lining of blood vessels, contributing to “hardening of the arteries.”
Some facilities screen for cardiovascular disease by performing heart scans which, in part, evaluate for calcium deposits in the lining of blood vessels and heart valves. A “calcium score” is calculated to help determine risk of cardiovascular disease.
Over half of adults take a calcium supplement, even though they may not need it. So here we have a dilemma: calcium is critical for bone strength and cell function but we had thought that supplements may contribute to cardiovascular disease, public enemy No. 1. Enter the researchers.
Scientists at the University of California San Francisco have reported their research findings indicating calcium supplements do not appear to contribute to cardiovascular disease in men or women. Their data indicate no association between calcium intake from diet or supplements and death due to myocardial infarction or stroke. However, the scientists warn not to exceed the recommended daily amounts of calcium.
The IOM recommends obtaining calcium through normal diet which includes green leafy vegetables, dairy, fortified foods and drinks, and enriched breads and cereals. Calcium intake should be addressed by patients with their physicians. Keep a food log. For some, supplements may be recommended. The two most common calcium preparations are calcium carbonate and calcium citrate. They are similarly absorbed, but the carbonate form is most commonly purchased because it is less costly. Vitamin D and/or magnesium aid absorption of calcium.
The IOM recommends that adults over age 19 consume between 1,000-1,200 mg calcium and 600-800 IU vitamin D daily from food and supplements. To maximize absorption it is recommended that doses be divided. For example, if 1,000 mg is recommended, it is best to take one 500mg tablet twice daily. But, this is only if you didn't get any calcium in your diet. Remember you are very likely getting adequate amounts in your food, so save your money.
Talk with your physician about your risk for bone disease and specific recommendations for your daily intake of calcium. And, eat your spinach.
Answers: 1. T; 2. F; 3. T.
Dr. Lori Boyajian-O’Neill can be contacted at firstname.lastname@example.org.