It’s hard to think of common medical folklore more ingrained than PSA tests for men and calcium supplements for women. And yet last week we had a couple of very strong studies which are questioning both of these fundamentals, causing an uproar for both sexes. So what’s the real deal here? Do I really have to change my practice? Actually, yes, I think I do — and I already have.
I will discuss PSA later and focus today on calcium, one of the most common supplements in the world. It seems that every woman takes calcium for “bone health”, including all the women in my family — both young and old. But a very disturbing new study says maybe most younger healthy women shouldn’t, as the risk of heart disease may outweigh any benefit in protecting bones from thinning. This recently published study followed over 24,000 women for 11 years and found that women who had calcium from their diet had a very encouraging decrease in risk of heart attacks. But those women who got their calcium mostly from supplements had a much higher risk of a heart attack — an 86% increase, in fact! And those women who totally avoided calcium foods and only got calcium from supplements had a very scary 239% increase in heart attacks. The take-home message, which was hinted at in previous studies, is now more clear: every woman should get their calcium from foods, not supplements! Here’s a good explanation from ScienceDaily.com:
The evidence that dietary calcium is helpful while calcium supplements are not can be explained by the fact that dietary calcium is taken in small amounts, spread throughout the day, so is absorbed slowly, they say.
Supplements, on the other hand, cause calcium levels in the blood to soar above the normal range, and it is this flooding effect which might ultimately be harmful, they suggest.
“Calcium supplements have been widely embraced by doctors and the public, on the grounds that they are a natural and therefore safe way of preventing osteoporotic fractures,” they write.
“It is now becoming clear that taking this micronutrient in one or two daily [doses] is not natural, in that it does not reproduce the same metabolic effects as calcium in food,” they say. Given that it is neither safe nor effective, boosting calcium intake from supplements should be discouraged, they contend. And they conclude: “We should return to seeing calcium as an important component of a balanced diet, and not as a low cost panacea to the universal problem of postmenopausal bone loss.”
What To Do? Foods…And Exercise
I’ve been discussing this study with my wife, and we’re now cutting back on her calcium supplements and trying to focus on more diet sources. I think this really should be a game-changer for the majority of younger women who are healthy and taking calcium supplements simply to protect their bones, especially those who avoid dairy products; it seems clear that they need to reconsider this and to seriously review their food choices for proper protection. I think the risk-benefit ratio is still favorable for older women and women who actually have osteoporosis, but in all cases the healthier approach for calcium intake is via foods. And please don’t forget exercise! Regular exercise is crucial to protect bone health as well.
How much calcium does a woman need, and which foods are best for this? Here’s a nice summary from WebMD:
Know Your Needs and Vitamin D
The Institute of Medicine recommends 1300mg calcium for anyone 9-18 years old, 1000mg for 19-70 year old men and 19-50 year old women, and 1200 mg for women over 50 and men over 70.
If vitamin D levels are too low, calcium may not be fully absorbed. It’s a good idea to check your levels at annual physicals.
Digging into Diet
Dairy is a simple way to meet calcium needs: 1 cup of low-fat milk or yogurt and 1 1/2oz of cheese contains about 300mg of calcium.
Other non-dairy foods that contain calcium include 1/2 cup tofu made with calcium sulfate (250mg); 1/2 cup greens like kale, collards, mustards (100mg); 1 cup fortified orange juice (500mg); 3oz canned salmon with bone (181mg); and calcium-fortified soy beverages and cereals (amount varies)
Other unlikely sources include nuts. For example, 1 cup of sliced almonds contains about 240mg while the same amount of mixed nuts and walnuts contain 100mg. Now, a cup is a lot, but the point is these healthy foods can help fill in calcium gaps.