JOURNAL: Am J Clin Nutr. 2002;76:365-372
AUTHORS: David J. A. Jenkins
ABSTRACT: Compared with a dairy diet, a soy-based diet improved lipid profile, yielding a calculated reduction in coronary artery disease (CAD) risk, according to a study published in the American Journal of Clinical Nutrition.
COMMENTARY: "Many of the benefits of soy have been attributed to soy isoflavones," write David J. A. Jenkins, from St. Michael's Hospital in Toronto, Ontario, and colleagues.
Study subjects included 23 men and 18 postmenopausal women with elevated cholesterol levels who rotated through three one-month diets that were all very low in saturated fat (less than 5% of energy and less than 50 mg/day of cholesterol). Protein sources were low-fat dairy products and egg substitute in the control diet, and low-fat soymilk and a variety of soy-based meat substitutes such as soy hot dogs and tofu burgers in the two soy protein-containing diets. The high-isoflavone diet contained 50 g soy protein and 73 mg isoflavones daily, and the low-isoflavone diet contained 52 g soy protein and 10 mg isoflavones daily.
Although serum concentrations of low-density lipoprotein (LDL) cholesterol were lower after the high-isoflavone diet, there were no major differences between the high- and low-isoflavone soy protein diets in their beneficial effects. After each soy diet, total cholesterol, LDL to high-density lipoprotein (HDL) ratio cholesterol, homocysteine concentrations, and systolic blood pressure in men were lower than they were after the control diet. Overall CAD risk calculated from blood lipid and blood pressure changes was 10.1%+/-2.7% lower with the soy diets than with the control diet.
STUDY: Neuropathy and Statins
JOURNAL: Neurology 2002;58:1321-1322, 1333-1337
AUTHORS: Dr. Michael Donaghy
ABSTRACT: Cholesterol-lowering drugs called statins may increase the risk of nerve damage called neuropathy, researchers from Denmark suggest.
COMMENTARY: But the well-known benefits of statins far outweigh the risk of neuropathy, which remains very low, the study's authors point out.
Peripheral neuropathy occurs when nerves in the peripheral nervous system--those outside of the brain and spinal cord--become damaged. Symptoms vary but may include tingling, numbness and burning pain as well as decreased sensitivity to temperature or pain. Diabetes, kidney disease, thyroid disease and alcohol abuse can all lead to neuropathy, but the nerve damage, known as polyneuropathy when it affects more than one nerve, may develop independently of these conditions.
As more and more people have started taking statins on a long-term basis, a small number of patients have developed cases of nerve damage with no apparent obvious cause. In a previous study, Dr. David Gaist, of the University of Southern Denmark in Odense, found that statins increased the risk of polyneuropathy, but the study was too small to be definitive.
Now, Gaist and his colleagues report the results of a larger study that seems to confirm the link between statins and neuropathy. In the population-based study in a Danish county, the researchers identified 166 first-time cases of neuropathy that did not have an obvious cause.
The cases were divided into definite, probable and possible cases depending on how certain the researchers were that the nerve damage could not have been caused by some other condition. Nine of the patients had taken statins, with the average length of treatment being nearly 3 years.
Compared to a "control" group of people who did not have neuropathy, people who had taken statins were 4 to 14 times more likely to develop polyneuropathy that did not have a known cause, according to the report published in the May 14th issue of the journal Neurology.
Several of the statins taken by patients in the study list peripheral neuropathy as a possible side effect. However, even though statins may increase the risk of developing nerve damage, the findings should not discourage the use of the cholesterol-lowering drugs, according to Gaist.
"The positive benefits of statins, particularly on reducing the risk of heart disease, far outweigh the potential risk of developing neuropathy," he said in a news release.
According to Gaist, "These findings shouldn't affect doctor or patient decisions to start using statins. But if people who take statins develop neuropathy symptoms, they should talk with their doctor, who may reconsider the use of statins."
"The overwhelming consideration is that, for those many patients for whom they are indicated, statins seem to provide a major reduction in the incidence of heart attack and stroke, and the many deaths associated with these disorders," Dr. Michael Donaghy, of the University of Oxford in the UK, told Reuters Health.
Any side effects of the drugs must be weighed against this "very substantial benefit," according to Donaghy, who is the author of a related editorial.
Donaghy notes that the study shows that polyneuropathy occurs in 1 out of every 2,200 patients who take statins. This nerve damage likely includes numbness, tingling and pain in the hands and feet, the Oxford physician points out. Although the severity of the neuropathy in patients taking statins is uncertain, Donaghy said it is "unlikely" to cause the same level of disability as a stroke, which might be prevented by statin use.
"Thus, the overall benefit-risk ratio of statins remains firmly in favor of using them in those patients for whom they are indicated to prevent cardiovascular disease," he concluded.
STUDY: Study finds vegetables in allium family beneficial
JOURNAL: Journal of the National Cancer Institute
AUTHORS: Ann Hsing
ABSTRACT: A study found that men who ate about a tenth of an ounce or more a day of garlic were about 50 percent less likely to have prostate cancer.
COMMENTARY: Men in China have the lowest rate of prostate cancer in the world, and a diet rich in garlic, shallots and onions may be one of the reasons. Researchers at the National Cancer Institute report in a new study that a diet with lots of vegetables from the pungent allium food group reduces the risk of prostate cancer by about half. And the common Chinese diet includes hearty servings of these vegetables.
The results showed that those who ate more than a third of an ounce a day from the allium food group — which consists of onions, garlic and shallots — were about 50 percent less likely to have prostate cancer than those who ate less of the foods.
Scallions seemed to be the most protective food in the group. According to the study, men who ate about a tenth of an ounce or more a day of scallions reduced their prostate cancer risk by about 70 percent. For garlic consumption of the same amount, the prostate cancer risk was reduced by about 53 percent.
The typical Chinese diet is much more heavily seasoned with garlic, scallions and onions than is the traditional American diet. But even so, the amount of allium vegetables consumed is measured only in fractional ounces. For instance, the study suggests that an effective level of prostate cancer protection can be achieved with about one clove of garlic a day.
Earlier studies have found that that eating tomatoes and tomato products can lower the risk of prostate cancer. Italy, where tomato sauce and garlic are favorites, has one of the lowest rates of prostate cancer in Europe.
This shows that your mother was right.
Eat more vegetables.
STUDY: What can we eat?
JOURNAL: Environmental Working Group
AUTHORS: Jane Houlihan
ABSTRACT: Farmed salmon, which Americans are scarfing down because it is supposed to be healthy, may actually be carrying high levels of cancer-causing chemicals called PCBs.
COMMENTARY: Wild salmon fished out of rivers and streams may actually be healthier for the time being.
Farmed salmon filets from 10 grocery stores in Washington, San Francisco, and Portland, Oregon, were tested and seven were contaminated with high levels of polychlorinated biphenyls.
"These first-ever tests of farmed salmon from U.S. grocery stores show that farmed salmon are likely the most PCB-contaminated protein source in the U.S. food supply," the group, a non-profit organization that investigates environmental matters, said in a statement.
"EWG's analysis of seafood industry fish consumption data shows that one quarter of all adult Americans (52 million people) eat salmon, and about 23 million of them eat salmon more often than once a month," the group said in a statement.
"Based on these data we estimate that 800,000 people face an excess lifetime cancer risk ... from eating farmed salmon."
They called on the U.S. Food and Drug Administration to do its own study and issue health warnings as needed.
They said their findings are supported by other studies done in Canada, Ireland and Britain.
PCBs come from hydraulic fluids and oils, electrical capacitors and transformers.
They are endocrine disrupters -- chemicals that act like hormones. They and related chemicals known as dioxins can cause cancer, infertility and perhaps other sexual changes.
STUDY: Popular procedure may have hidden risks,studies find
JOURNAL: Obstetrics & Gynecology
AUTHORS: Dr. Evan Myers
ABSTRACT: An increasingly popular treatment promises to rid women of painful, bleeding uterine fibroids without standard surgery’s risks. But new research has some doctors questioning how long the treatment helps — and if it’s too risky for women who hope to become pregnant.
COMMENTARY: Part of the problem is that this new “uterine artery embolization” has never been fully studied to see how it compares with uterine-sparing surgical removal of fibroids.
But the controversy highlights a bigger issue: “We really don’t know very much at all about how to manage fibroids,” says Dr. Evan Myers of Duke University — even though the uterine growths plague more than a million women a year and are the leading cause of hysterectomies.
Nearly 40 percent of women in their 30s and 40s develop fibroids, non-cancerous growths of muscle fibers inside the uterus. No one knows what causes fibroids, and tiny ones usually cause no symptoms. But they can grow to cantaloupe size, causing severe pain, heavy bleeding and infertility or pregnancy complications.
More than 150,000 hysterectomies — surgical uterus removal — each year are due to fibroids.
For women who still want children, options are limited. Drugs shrink fibroids only temporarily. About 35,000 women a year undergo myomectomy, where surgeons remove fibroids while leaving the uterus intact. But it’s painful, fibroids sometimes grow back, and women who later become pregnant usually require Caesarean deliveries.
Uterine artery embolization, or UAE, is a far less invasive alternative.
Doctors squirt tiny plastic pellets into certain uterine arteries, cutting off the blood supply feeding the fibroids. Over the next three months to a year, the fibroids shrink.
About 85 percent of patients get relief, fueling UAE’s growing popularity. Some 30,000 embolizations have been performed since UAE was first tried in 1995, says Myers, who calls it a promising procedure.
But studies published this month in Obstetrics & Gynecology raise questions about how long that relief lasts — and stress that contrary to public perception, UAE isn’t risk-free.
The University of California, Los Angeles, tracked 59 UAE patients and another 38 who had a myomectomy. Three years later, 29 percent of the UAE patients needed further fibroid treatment; only 3 percent of myomectomy patients did.
Infection, bleeding and blood-vessel clots are considered serious but rare risks of UAE — at least two deaths have been reported since 1995 — although no one knows how often complications occur.
Georgetown University Hospital tracked 400 embolization patients treated there since 1997, and concluded the overall risk of side effects was a low 5 percent. Most were minor — but five patients required days of hospitalization for infection, bleeding or clots. One needed a hysterectomy four months after her UAE, for heavy bleeding when her body expelled a shrunken fibroid. Researchers at Thomas Jefferson University analyzed the 50 published cases of pregnancy after UAE and concluded those women had higher risks of miscarriage, post-delivery hemorrhage, premature birth, breech babies and Caesarean sections than do healthy women. Other researchers say infertility also may be a risk if UAE accidentally blocks blood flow to the ovaries.
Meanwhile, any of the options is reasonable for a woman no longer considering pregnancy, but know that retreatment rates for both UAE and myomectomy remain in question, Myers says.
If women want to become pregnant, they “really need to know they’re taking a chance” with UAE, he adds. Georgetown’s Spies recommends myomectomy in particular for anyone wanting a baby within two years, because UAE shrinks fibroids so slowly.
"Do a little digging” before picking a doctor, adds Cynthia Pearson of the National Women’s Health Network, which urges better fibroid research. “No matter how fabulous things were at Georgetown, a woman can’t assume her results will be the same” if her doctor hasn’t performed many UAEs.