Soy and osteoporosis: The bone hard facts
By Angel S. Respicio, Jr. MD Updated May 19, 2009 12:00 AM
MANILA, Philippines – There’s so much emphasis on the positive role of soy in preventing osteoporosis. Soy was hailed as the wonder food ever since soy lobbyists successfully persuaded the USFDA to approve it in 1999. Taking their cue, the American Heart Association fell to the soy industry’s ploy in 2000 despite concerns from Dr. Francis Crinella, Dr. Joseph Mercola, and Kaayla T. Daniel PhD.
According Dr. Francis Crinella at the University of California, the soybean plant lifts up manganese in the soil and concentrates it, creating levels of manganese in soy formulas that are 200 times the level found in breast milk. A newborn cannot excrete this extreme manganese load, creating high manganese levels in the blood, liver, kidneys, and other soft tissues of the body, including the brain. Manganese overload has been implicated in cases of brain damage and movement disorders.
Dr. Joseph Mercola, on the other hand, notes in his newsletter that soy formulas contain high levels of aluminum (1,000 percent higher than cow’s milk formulas) and the phytoestrogen substance isoflavones. He says that a soy-fed baby receives the equivalent of five birth control pills’ worth of estrogen every day. These babies’ isoflavone levels were found to be from 13,000 to 22,000 times higher than in non-soy-fed infants. Early onset of puberty in girls and abnormal development of testes in boys have been linked to this unnatural surge of hormones in early life.
Some health practitioners advise us to avoid meat and eat tofu for better bone health, but Kaayla Daniel, PhD thinks otherwise. In her absorbing article “Soy and Osteoporosis: Not a Leg to Stand On,” she busts the myths head on.
Soy as the all-natural solution for osteoporosis? The latest ploy of the soy industry is to fan women’s fears about bone loss and distract them from recent news that soy does not prevent heart disease, and that it worsens cardiomyopathy, impairs fertility, and may increase breast cancer risk.
Consumers who bone up on the issue, however, will find that the research is inconsistent and contradictory at best, and that soy truly does not have a leg to stand on. A recent study that the industry has chosen not to promote came out of Yale New Haven Hospital in July and compared calcium bioavailability in women eating soy versus those eating meat. The researchers concluded in the Journal of Nutrition, “These data indicate that when soy protein is substituted for meat protein, there is an acute decline in dietary calcium bioavailability.”
This finding explodes a myth widely propagated by vegetarians, namely that meat and eggs cause a loss of calcium, leading the body to strip calcium from storage in the bones, ultimately resulting in osteopenia or osteoporosis.
The study most often cited to justify this claim came out in 1988 in the Journal of Clinical Endocrinology and Metabolism. Those who got their protein from animal products lost 50 percent more calcium from their bodies than did those who had only soy protein. The researchers concluded, “The inability to compensate for the animal protein-induced calciuric response (meaning calcium in the urine) may be a risk factor for the development of osteoporosis.”
What is never mentioned in this study is that the 15 subjects spent a grand total of 12 days testing each type of food. This was just enough time for their bodies to react to unexpectedly high levels of sulfur proteins, but not enough time for the body to normalize and handle the sulfur load. Calcium homeostasis is normally well regulated so that increased calcium loss through the urine results in increased calcium absorption from the gut. This adaptive process may fail to occur during short-term studies but the human body is more than capable of adjusting to the sulfur load of real foods, given a proper time frame.
The evidence that soy isoflavone supplements stem bone loss was based on the results of bone density tests. These tests measure bone quantity but not quality, and fail to acknowledge that thin bones can be strong, flexible, and healthy while thick bones can be brittle and friable. If soy isoflavones, in fact, stop bone resorption, the result could be chalky big bones that crumble. This is exactly what’s happening with some women whose bone mass has been “preserved” with drugs like Fosamax.
Notably, people and animals fed real food have not experienced the same problems, so cutting back on sulfur-rich foods is not the solution to osteoporosis.
Malnutrition in Children
Evidence that soy milk does not promote healthy bone growth in children has even begun to appear in the mainstream press. A May 8, 2006 Newsweek article entitled “Does Milk Hurt Kids?” warned readers that children given rice and soy-based milk substitutes were showing rickets and other signs of malnutrition once found almost exclusively among the famished in third world countries. Soy milk, of course, contains phytates, which block the proper absorption of calcium, zinc, and other minerals needed for proper bone growth.
Although calcium supplements are added to soy milk to compensate for theft by phytates, the cheap powders are hard to absorb or not swallowed at all because of the powder’s tendency to either clump at the bottom or stick to the walls of the container.
Commercial soy milk also contains vitamin D2 (ergocalciferol), the ineffective vegetarian form of vitamin D that offers few of the benefits of true vitamin D3 (cholecalciferol) and has been linked to hyperactivity, coronary heart disease, and allergic reactions. Even the cheapest dairy milk sold in supermarkets uses vitamin D3, but soy milk manufacturers use D2, the only form accepted by soymilk-swigging vegans.
Dr. Daniel reminds us that soy milk is high in sugar, a well-known bone hazard. Most brands add between one teaspoon and one tablespoon per glass.
On January 17, 2006, the American Heart Association has had enough and withdrew their support for soy and soy-based products. The health claims from the soybean-funded studies were actually exaggerated and false.
D Bare Facts
Now, to make that calcium prevent osteoporosis, you need vitamin D. Let me clear a misinformation. The sun is not a source of vitamin D, it will never be! It only activates the “inactive” form of vitamin D which is found under the skin. The best time to maximize the activating power of the sunlight is from 10 a.m. to 3 p.m. Avoid taking a bath in your house or soaking in chlorinated pools for at least an hour for the sun-activated vitamin D to be absorbed properly. Vitamin D occurs naturally in fatty fish, cod liver oil, liver, animal fat, and egg yolk. It is also synthesized (manufactured) by the body from cholesterol. Egg yolk, therefore, should be consumed regularly and if you have concerns with stroke, fear no more. Dr. Anthony L. Komaroff of the Harvard Health Letter assured us when he said, “People who eat an egg a day are no more likely to have heart disease than those who eat eggs less than once a week.”
By the way, vitamin D can only be absorbed in the gut in the presence of fat. If you are taking vitamin D supplements without the required fat, you are just putting that essential vitamin down the drain. Did you ever wonder why skim milk, low-fat milk, and fat-free milk, even if fortified with calcium and vitamin D, do not benefit your bones if at all?
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