| Autumn
2004 • Volume XIII, Number 4
THE LATEST IN...
Mice Are Not Men…Or Women
Much
of what government regulators thought they knew about the health
effects of industrial chemicals, such as PCBs, came from rodent
experiments and is now being contradicted by a new human study.
Researchers at the University of California found that many PCBs
block steroid and xenobiotic receptors in humans rather than activate
them, as tests on rats had suggested. PCBs were banned in 1976 in
the United States due to their toxicity, but still persist in the
soil, air, and water. They accumulate in the livers of animals,
causing brain damage, cancer, and other problems.
Tabb MM, Kholodovych V, Grun F, Zhou C, Welsh WJ,
Blumberg B. Highly chlorinated PCBs inhibit the human xenobiotic
response mediated by the steroid and xenobiotic receptor (SXR).
Environ Health Perspect 2004;112:163-9.
Manipulated Results
Clinical researchers routinely alter the results of their studies
to present the outcomes they desire, according to a study from Oxford
University. A research team reviewed the results of more than 100
scientific trials and discovered that “inconvenient”
findings were often not reported to the public. In half of the cases,
the stated purpose of the trial was altered as it progressed so
that acceptable findings could be published. The same percentage
omitted crucial information about the effectiveness of a certain
treatment or potential harmful effects.
Chan AW, Hrobjartsson A, Haahr MT, Gotzsche PC,
Altman DG. Empirical evidence for selective reporting of outcomes
in randomized trials: comparison of protocols to published articles.
JAMA 2004;291:2457-65.
Eating Fish Exposes Babies to Mercury
The EPA estimates that mercury exposures in the womb may put more
than 600,000 babies each year at risk for birth defects or learning
disabilities. The findings, which are nearly double previous estimates,
stem from a new understanding that umbilical cord blood has 1.7
times more mercury than mother’s blood. One in six U.S. women
of childbearing age has enough mercury in her blood to affect her
child, the main sources of exposure being tuna, swordfish, shark,
and other large fish.
Kaiser Family Foundation Report, February 2004.
Good Carbs Great for Weight Loss
After
12 weeks on a high-carbohydrate eating plan, both men and women
lost more weight and body fat than a control group consuming a similar
number of calories from fattier foods. According to research from
the Archives of Internal Medicine, participants lost about 7 pounds
by consuming low-fat, high-carb foods for 12 weeks with no restriction
on portion sizes. Adding moderate exercise increased the loss to
11 pounds. Similar to past research, the study demonstrates that
low-fat, complex carbohydrate-rich foods are excellent for facilitating
weight loss.
Hays NP, Starling RD, Liu X, et al. Effects of an
ad libitum low-fat, high-carbohydrate diet on body weight, body
composition, and fat distribution in older men and women. Arch Intern
Med 2004;164:210-7.
Fiber-Rich Diet Lowers Heart Disease Risk
Dietary fiber from cereal and fruit lowers risk for coronary heart
disease in men and women, according to a report in the Archives
of Internal Medicine. Researchers analyzed data from ten studies
involving more than 90,000 men and more than 240,000 women in the
United States and Europe, finding that every 10 grams of fiber in
the daily diet is associated with a 14 percent reduction for all
coronary events and a 27 percent reduction in coronary deaths.
In a second study, adults consuming the most dietary fiber had
the lowest serum concentrations of C-reactive protein (CRP), a marker
of inflammation that may predict future cardiovascular events, according
to a study including 4,000 men and women over 20 years of age. Fiber
is found in beans, vegetables, fruits, and whole grains and is not
found in animal-derived products.
Pereira MA, O’Reilly E, Augustsson K, et al.
Dietary fiber and risk of coronary heart disease. Arch Intern Med
2004;164:370-6.
Ajani UA, Ford ES, Mokdad AH. Dietary fiber and c-reactive protein:
finding from National Health and Nutrition Examination Survey data.
J Nutr 2004;134:1181-5.
Soymilk Lowers “Bad” Cholesterol
Soymilk
cuts cholesterol, according to researchers in Sao Paulo, Brazil.
The research team put 60 outpatients, ages 20 to 70, on a cholesterol-lowering
diet for six weeks. They then added either soymilk or non-fat cow’s
milk to the diet for six weeks. Subsequently, the treatments were
switched: those drinking soymilk consumed non-fat cow’s milk
and vice versa. In the soymilk group, low-density lipoprotein (“bad”)
cholesterol fell 9 mg/dl, whereas the dairy group’s “bad”
cholesterol increased 1 mg/dl. The soymilk group’s high-density
lipoprotein (“good”) cholesterol increased 4 mg/dl,
whereas the nonfat dairy group’s “good” cholesterol
decreased 1 mg/dl.
Bricarello LP, Kasinski N, Bertolami, MC, et al. Comparison between
the effects of soymilk and non-fat cow milk on lipid profile and
lipid peroxidation in patients with primary hypercholesterolemia.
Nutrition 2004;20:200-4.
Hormones Linked to Stroke and Blood Clots
Premarin
increases the risk of stroke and dangerous blood clots in postmenopausal
women, findings that have caused another portion of the long-running
Women’s Health Initiative (WHI) to be terminated early. As
reported in the Journal of the American Medical Association,
the study was conducted in 40 U.S. cities beginning in 1993, including
more than 10,000 women, 50 to 79 years of age, who had undergone
a hysterectomy. Previous WHI findings found that hormones do not
protect women from heart disease as doctors once believed and actually
increase heart disease and cancer risk.
Anderson GL, Limacher M, Assaf AR, et al. Effects
of conjugated equine estrogen in postmenopausal women with hysterectomy:
the Women’s Health Initiative randomized controlled trial.
JAMA 2004;291:1701-12.
Media
Center | Health | Research
| About PCRM | Catalog
| Join Us | Search
| Site Index | Home
The site does
not provide medical or legal advice. This Web site is for information purposes
only.
Full Disclaimer | Privacy Policy
|