Consumer Health Digest #07-09

Your Weekly Update of News and Reviews
February 27, 2007

Consumer Health Digest is a free weekly e-mail newsletter edited by Stephen Barrett, M.D., and cosponsored by NCAHF and Quackwatch. It summarizes scientific reports; legislative developments; enforcement actions; news reports; Web site evaluations; recommended and nonrecommended books; and other information relevant to consumer protection and consumer decision-making.

Garlic flunks major test. A double-blind clinical trial of garlic and garlic supplements found no improvement in cholesterol levels among 192 adults with moderately elevated (130 to 190mg/dL) LDL-cholesterol levels. The participants were randomly divided into groups that received raw garlic, a powdered garlic supplement, an aged garlic extract supplement, or a placebo for six months. Garlic product doses equivalent to an average-sized garlic clove were consumed 6 days per week for 6 months. The study found no statistically significant difference in high-density lipoprotein cholesterol, triglyceride levels, or total cholesterol–high-density lipoprotein cholesterol ratio in the four groups. [Gardner CD and others. The researchers noted that idea that garlic could improve cholesterol levels was considered plausible because about 85% of more than 110 animal studies found positive effects and human clinical trials conducted before 1995 with garlic powder tablets suggested a modest beneficial effect. However: (a) animal studies may not be applicable to humans, (b) the pre-1995 human trials were not well-designed, and (c) six more recent trials found no benefit. The researchers concluded:

Based on our results and those of other recent trials, physicians can advise patients with moderately elevated LDL . . . concentrations that garlic supplements or dietary garlic in reasonable doses are unlikely to produce lipid benefits. While garlic may have other health effects, such as increased fibrinolysis, decreased atherosclerosis, or anticarcinogenic properties, we would argue that these possible effects also should be scrutinized in large, carefully designed trials with chemically defined garlic products. [Gardner CD. Effect of raw garlic vs commercial garlic supplements on plasma lipid concentrations in adults with moderate hypercholesterolemia. Archives of Internal Medicine 167:346-353, 2007]

Because several drugs have been proven to improve cholesterol levels and reduce the incidence of heart attacks and death, it also can be argued that substituting garlic for that purpose is senseless. In a Los Angeles Times interview, lead author Christopher Gardner said: "It just doesn't work. If garlic was going to work, in one form or other, then it would have worked in our study. The lack of effect was compelling and clear." The study was supported by a $1.5 million NIH grant.

Pakistani public health leader murdered. Dr. Abdul Ghani Marwat, who headed the Pakistan government’s polio vaccination campaign in Bajaur tribal district near the Afghan border, was killed by a roadside bomb (the same type used by the Iraqi resistance against U.S. occupation forces) while returning after meeting a local religious leader. Two other health workers were injured, one fatally. The blast came amid rumors that the vaccination drive was part of a Western plot to sterilize Muslim children. Some 1,500 health officials, including doctors, nurses and paramedical staff, reacted by wearing black armbands and executing a strike to protest the killing and lack of security. The Pakistani government has said that the parents of some 24,000 children had refused to give them the polio vaccine because of opposition by Muslim clergy [Health workers boycott polio vaccination in Bajaur Agency. The Pakistan Daily Times, Feb 20, 2007] Pakistan is one of only a handful of countries countries in Asia and Africa where polio has not been wiped out.

Lavender and tee tree oils display unwanted hormone activity. Cases have been reported of otherwise healthy 4, 7, and 10-year-old boys who developed breast enlargement after applying skin-care products that contained lavender or tea tree oils to their skin. One product was a "healing balm." The others included a gel, a shampoo, a soap, and a lotion. The problem resolved shortly after use of the products was stopped. The authors of the report also did cell-culture studies which found that both oils have female (estrogen) and anti-male hormone properties that can cause endocrine imbalance. [Henley DV. Prepubertal gynecomastia linked to lavender and tea tree oils. New England Journal of Medicine 356:479-485, 2007]

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This page was posted on February 7, 2007.