Killing Us Softly: The Sense and Nonsense of Alternative Medicine. Dr Offit Paul

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СКАЧАТЬ Moertel performed a second study; the results were the same. Moertel concluded, “Among patients with measurable disease, none had objective improvement. It can be concluded that high-dose vitamin C therapy is not effective against advanced malignant disease regardless of whether the patient had received any prior chemotherapy.” For most doctors, this was the end of it. But not for Linus Pauling. He was simply not to be contradicted. Cameron observed, “I have never seen him so upset. He regards the whole affair as a personal attack on his integrity.” Pauling thought Moertel’s study was a case of “fraud and deliberate misrepresentation.” He consulted lawyers about suing Moertel, but they talked him out of it.

      Subsequent studies have consistently shown that vitamin C doesn’t treat cancer.

      Pauling wasn’t finished. Next, he claimed that vitamin C, when taken with massive doses of vitamin A (25,000 international units) and vitamin E (400 to 1,600 IU), as well as selenium (a basic element) and beta-carotene (a precursor to vitamin A), could do more than just prevent colds and treat cancer; they could treat virtually every disease known to man. Pauling claimed that vitamins and supplements could cure heart disease, mental illness, pneumonia, hepatitis, polio, tuberculosis, measles, mumps, chickenpox, meningitis, shingles, fever blisters, cold sores, canker sores, warts, aging, allergies, asthma, arthritis, diabetes, retinal detachment, strokes, ulcers, shock, typhoid fever, tetanus, dysentery, whooping cough, leprosy, hay fever, burns, fractures, wounds, heat prostration, altitude sickness, radiation poisoning, glaucoma, kidney failure, influenza, bladder ailments, stress, rabies, and snakebites. When the AIDS virus entered the United States in the 1970s, Pauling claimed vitamins could treat that, too.

      On April 6, 1992, the cover of Time—rimmed with colorful pills and capsules—declared, “The Real Power of Vitamins: New research shows they may help fight cancer, heart disease, and the ravages of aging.” The article, written by Anastasia Toufexis, echoed Pauling’s ill-founded, disproved notions about the wonders of megavitamins. “More and more scientists are starting to suspect that traditional medical views of vitamins and minerals have been too limited,” wrote Toufexis. “Vitamins—often in doses much higher than those usually recommended—may protect against a host of ills ranging from birth defects and cataracts to heart disease and cancer. Even more provocative are glimmerings that vitamins can stave off the normal ravages of aging.” Toufexis enthused that the “pharmaceutical giant Hoffman-La Roche is so enamored with beta-carotene that it plans to open a Freeport, Texas, plant next year that will churn out 350 tons of the nutrient annually, or enough to supply a daily 6 milligram capsule to virtually every American adult.”

      The National Nutritional Foods Association (NNFA), a lobbying group for vitamin manufacturers, couldn’t believe its good luck, calling the Time article “a watershed event for the industry.” As part of an effort to get the FDA off their backs, the NNFA distributed multiple copies of the magazine to every member of Congress. Speaking at an NNFA trade show later in 1992, Toufexis said, “In fifteen years at Time I have written many health covers. But I have never seen anything like the response to the vitamin cover. It whipped off the sales racks, and we were inundated with requests for copies. There are no more copies. ‘Vitamins’ is the number-one-selling issue so far this year.”

      Although studies had failed to support him, Pauling believed that vitamins and supplements had one property that made them cure-alls, a property that continues to be hawked on everything from ketchup to pomegranate juice and that rivals words like natural and organic for sales impact: antioxidant.

      Antioxidation vs. oxidation has been billed as a contest between good and evil. The battle takes place in cellular organelles called mitochondria, where the body converts food to energy, a process that requires oxygen and so is called oxidation. One consequence of oxidation is the generation of electron scavengers called free radicals (evil). Free radicals can damage DNA, cell membranes, and the lining of arteries; not surprisingly, they’ve been linked to aging, cancer, and heart disease. To neutralize free radicals, the body makes its own antioxidants (good). Antioxidants can also be found in fruits and vegetables—specifically, selenium, beta-carotene, and vitamins A, C, and E. Studies have shown that people who eat more fruits and vegetables have a lower incidence of cancer and heart disease and live longer. The logic is obvious: if fruits and vegetables contain antioxidants—and people who eat lots of fruits and vegetables are healthier—then people who take supplemental antioxidants should also be healthier.

      In fact, they’re less healthy.

      In 1994, the National Cancer Institute, in collaboration with Finland’s National Public Health Institute, studied 29,000 Finnish men, all long-term smokers more than fifty years old. This group was chosen because they were at high risk for cancer and heart disease. Subjects were given vitamin E, beta-carotene, both, or neither. The results were clear: those taking vitamins and supplements were more likely to die from lung cancer or heart disease than those who didn’t take them—the opposite of what researchers had anticipated.

      In 1996, investigators from the Fred Hutchinson Cancer Research Center, in Seattle, studied 18,000 people who, because they had been exposed to asbestos, were at increased risk of lung cancer. Again, subjects received vitamin A, beta-carotene, both, or neither. Investigators ended the study abruptly when they realized that those who took vitamins and supplements were dying from cancer and heart disease at rates 28 and 17 percent higher, respectively, than those who didn’t.

      In 2004, researchers from the University of Copenhagen reviewed fourteen randomized trials involving more than 170,000 people who took vitamins A, C, E, and beta-carotene to see whether antioxidants could prevent intestinal cancers. Again, antioxidants didn’t live up to the hype. The authors concluded, “We could not find evidence that antioxidant supplements can prevent gastrointestinal cancers; on the contrary, they seem to increase overall mortality.” When these same researchers evaluated the seven best studies, they found that death rates were 6 percent higher in those taking vitamins.

      In 2005, researchers from Johns Hopkins School of Medicine evaluated nineteen studies involving more than 136,000 people and found an increased risk of death associated with supplemental vitamin E. Dr. Benjamin Caballero, director of the Center for Human Nutrition at the Johns Hopkins Bloomberg School of Public Health, said, “This reaffirms what others have said. The evidence for supplementing with any vitamin, particularly vitamin E, is just not there. This idea that people have that [vitamins] will not hurt them may not be that simple.” That same year, a study published in the Journal of the American Medical Association evaluated more than 9,000 people who took high-dose vitamin E to prevent cancer; those who took vitamin E were more likely to develop heart failure than those who didn’t.

      In 2007, researchers from the National Cancer Institute examined 11,000 men who did or didn’t take multivitamins. Those who took multivitamins were twice as likely to die from advanced prostate cancer.

      In 2008, a review of all existing studies involving more than 230,000 people who did or did not receive supplemental antioxidants found that vitamins increased the risk of cancer and heart disease.

      On October 10, 2011, researchers from the University of Minnesota evaluated 39,000 older women and found that those who took supplemental multivitamins, magnesium, zinc, copper, and iron died at rates higher than those who didn’t. They concluded, “Based on existing evidence, we see little justification for the general and widespread use of dietary supplements.”

      Two days later, on October 12, researchers from the Cleveland Clinic published the results of a study of 36,000 men who took vitamin E, selenium, both, or neither. They found that those receiving vitamin E had a 17 percent greater risk of prostate cancer. In response to the study, Steven Nissen, chairman of cardiology at the Cleveland Clinic, said, “The concept of multivitamins was sold to Americans by an eager nutraceutical industry to generate profits. There was never any scientific data supporting their usage.” On October 25, a headline in the Wall Street Journal СКАЧАТЬ