"Strong To the Bone"
by Victoria Dolby Toews, M.P.H
from Better Nutrition magazine
More than 28 million Americans have been diagnosed with osteoporosis, 80 percent of whom are women. According to the National Institutes of Health (NIH), another 18 million have low bone mass, meaning they're at risk for the disease. And half of all American women over age 50 will suffer an osteoporosis-related fracture in their lifetime. What's particularly frightening about this disease is that it siphons away the strength of your bones without any symptoms. It results in 1.5 million fractured or broken bones annually-often leading to permanent disability-and nearly a quarter of hip-fracture patients over 50 die within a year of their fracture.
While osteoporosis can hit anyone, post-menopausal women are at the greatest risk. For starters, most women don't get enough calcium in the course of their lifetime. When this accumulated deficiency is coupled with the plummeting estrogen levels of menopause, bone mass is quickly lost. According to the NIH, women can lose up to 20 percent of their bone mass in the first five to seven years following menopause, making them more susceptible to osteoporosis. The good news is that the diseases is considered higly preventable, with proper nutrition and exercise the keys to developing-and maintaining-strong, fracture-resistant bones.
Today's standard American diet, however, especially for women, falls short when it comes to calcium. That, plus contemporary lifestyle habits-smoking, caffeine, soft drinks, too much stress and not enough exercise-rob us of the little calcium we have managed to store. In fact, the Food and Nutrition Board (which sets the Dietary Reference Intakes and RDAs) says that the average woman only consumes between 530 and 785 milligrams (mg.) per day of this important mineral-far less than the daily 1,000 mg. recommended for premenopausal women and the 1,200 mg. for women ages 51-70.
Many people overlook the fact that calcium requires the presence of several other minerals and vitamins to be properly absorbed. Key among them is magnesium. While there is some debate over the percentages, most research suggests that a 2-to-1 ratio of calcium to magnesium is optimal, with a daily magnesium intake (through food and supplementation) of 500 to 600 mg. (with a maximum of 350 mg. of nonfood source for pregnant and nursing women).
The other essential bone-building "cohorts" include boron (3 to 6 mg.), manganese (2 to 5 mg.), potassium (630 mg. or one banana), lysine (50 mg.), and vitamins A (5,000 international units), B6 (1.6 to 10 mg.), C (1,000 mg.), E (400 IU), and K (65 to 100 micrograms). Additionally, vitamin D helps turn calcium into bone. Although human skin can synthesize enough vitamin D from just 15 minutes of direct sunlight, many people simply do not make enough of this vitamin due to geography, clothing choices, or staying inside. As little as 200 U of vitamin D daily prevents softening of the bones, though more is needed to stave off osteoporosis (400 IU per day).
Also critical for bone-building are isoflavones, estrogen-like plant hormones. The primary isoflavones in soy-genistein and daidzein-help maintain bone density. Incorporating soy into the diet can make a difference, says Mark Messina, Ph.D.,M.S., Loma Linda University, Loma Linda, California, who recommends 50 to 60 mg. of isoflavones daily (roughly 1 cup of soy milk or 4 oz. of tofu.
According to Elizabeth Somer, R.D., author of The Origin Diet (Henry Holt 2000), omega-3 fats turn on prostaglandin production., which triggers bone cells to deposit calcium. "Omega-3s also help boost calcium absorption and enhance the action of vitamin D in bone building," she says. Take approximately 1,000 mg. of omega-3 fats (flaxseed oil, nuts, seeds) and 7,000 mg. of omega-6 fats (vegetable oils).
In years past, the skeleton was viewed as a hard, unchanging frame for
the body. But now we know that the bones are in a constant state of flux.
Keeping them strong requires dedication to a sensible diet, regular exercise
and a few well-chosen supplements. These new insights into bone health
should give hope to millions of women.