The calcium paradox


wellness solutions from a natural perspective This mineral mainstay still does a body good. But for stronger bones, eat less meat and dairy

a DAILY CALCIUM PILL has been the supplemental mantra of millions of women — that is, until earlier this year, when the largest, most rigorous investigation to date showed that calcium supplements do little or nothing to prevent osteoporosis and resulting bone fractures.

The headline-grabbing study, published in The New England Journal of Medicine, involved 36,282 women ages 50 to 79, who took either a daily placebo or 1,000 milligrams of calcium (plus 400 IU of vitamin D to help absorption). After seven years, the calcium takers experienced a slight increase in bone mineral density, the standard measure of bone health, but no reduction in osteoporotic fractures.

The news wasn't unprecedented. In a National Academy of Sciences review of 31 calcium trials, 61 percent showed no significant increase in bone mineral density. And a Harvard study that tracked 77,761 women for 12 years found that women who drank two or more glasses of milk a day actually had a greater risk of hip fracture than those who drank little or no milk.

"Americans accept the idea that a high-calcium diet and calcium supplements build strong bones," says Amy Joy Lanou, Ph.D., assistant professor of nutrition at the University of North Carolina at Asheville, "But if you analyze the data, it's just not the case."

Consider Chinese food, which has little or no dairy. Yet studies show that Chinese women are less likely to suffer hip fractures than white American women who drink milk, eat yogurt and cheese, and take calcium. "It's the calcium paradox," says anthropologist-nutritionist Susan E. Brown, Ph.D., director of the Osteoporosis Education Project in East Syracuse, NY. "People in China, Peru, and Africa maintain healthy bones on 400 to 500 milligrams of calcium a day, while many in the West develop brittle bones on 1,500 milligrams of calcium a day."

Osteoporosis prevention is a delicate balance between acids and alkalines, Brown explains. For the body to function normally, blood cannot become too acidic or too alkaline. When blood does get too acidic, the body may release alkaline calcium compounds from bone to neutralize it.
The High-Acid Diet

A high-protein diet floods the blood with acid-forming, sulfurous amino acids. Unless the protein is offset by a diet rich in alkaline-forming plant foods, the body neutralizes the acid by releasing calcium from bone. According to the NAS, every gram of ingested protein increases calcium excretion in urine by about 1 mg — numbers that can become substantial over several decades. "If you eat a typical American diet with lots of meat and dairy, you lose bone," notes Lanou. "But if you eat a plant-based diet with minimal meat and dairy, calcium remains where you want it to — in your bones." Reducing your intake of salt, caffeine, and cola also protects bones. (For more on achieving acid alkaline balance, see "pH Power" in the November 2005 issue or at

Oh, and keep taking vitamin D. A Harvard analysis showed that 700 to 800 IU daily reduces hip-fracture risk by 26 percent. Another bonebuilder is weight-bearing exercise, ideally at least 30 minutes per day. "I recommend walking, dance, or aerobics," Lanou says. If you have access to free weights, do resistance exercises, which strengthen bones and improve muscle mass.

"Exercise every day, and eat more fruits and vegetables and less meat and dairy," says Lanou. "This is good health advice in general. And it's good advice for healthy bones."

Calcium continues to deserve a place on your supplement shelf. A great deal of research shows that dietary and supplemental calcium decreases the risk of high blood pressure, a key factor in heart attack and stroke. Some studies have found that daily calcium reduces the recurrence of precancerous polyps in the intestinal tract. The mineral is also essential for muscle contractions.

The National Academy of Science's Institute of Medicine advises women and men ages 19 to 50 to consume 1,000 milligrams of calcium a day, while people 51 and older need 1,200 mg daily. If you're eating fewer dairy foods because of their animal proteins, you may need to take supplements. Calcium citrate is generally preferred, since it absorbs better than calcium carbonate and doesn't contain mercury like some coral calcium.

So go ahead and take calcium. (My wife, a doctor, takes 1,000 mg a day.) Studies have yet to be done, but it's logical that your calcium supplement will perform even better once you've adopted a more alkaline, plant-based diet. — M.C

PHOTO (COLOR): PROTECT YOUR BONES by switching to vegetarian proteins like lentils, tofu, and Brussels sprouts.


By Michael Castleman

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