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High Cholesterol and Suicide
The first study of its kind has linked high serum cholesterol levels with violent suicide. Researchers found a two-fold increase in deaths by firearms, explosives, hanging, cutting, and other extreme measures, comparing subjects with the highest and lowest serum cholesterol concentrations. During this century, the Western world has seen increasing rates of depression—one of the strongest risk factors for suicide—which may be caused in part by greater consumption of saturated fatty acids and lower intake of polyunsaturated fatty acids.
Cholesterol, made naturally by the liver, holds together cell membranes and is the raw material that builds hormones. A diet that includes cholesterol and saturated fat from animal products can quickly put cholesterol levels in the danger zone. In contrast, plant foods contain no cholesterol and little saturated fat, allowing the body to maintain its own healthy balance.
Past studies have shown that men who have more sex-hormone binding globulin (SHBG) in their blood are less domineering and aggressive. SHBG is boosted by a diet rich in plant foods and guards against testosterone's negative effects by holding it at bay until it is needed by the body.
Tanskanen A, Vartiainen E, Tuomilehto J, et al. High serum cholesterol and risk of suicide. Am J Psychiatry 2000;157:648-50.
© 2001, PHOTODISC
Hormones Do Not Halt Alzheimer's Disease...But Vegan Foods May
Researchers randomly assigned 120 patients with mild to moderate Alzheimer's disease to take low-dose estrogen, high-dose estrogen, or a placebo for 12 months. There was no significant difference in functional and cognitive outcomes in those who received ERT and those who did not.
However, at the World Alzheimer's Congress 2000 in Washington, D.C., two reports showed promise that fruits and vegetables protect against the disease. Researchers observed the dietary habits of nearly 8,000 men and women free of dementia upon enrolling in the study. When re-examined six years later, those who ate foods rich in vitamins E and C were less likely to have developed Alzheimer's disease.
Mulnard RA, Cotman CW, Kawas C, et al. Estrogen replacement therapy for treatment of mild to moderate Alzheimer's disease: a randomized controlled trial. Alzheimer's Disease Cooperative Study. JAMA 2000;283:1007-15.
Better Cardiovascular Health Prevents Dementia
Reducing high blood pressure, losing excess body weight, and keeping cholesterol levels under control are fundamental keys for good health. A new study has shown these steps may also help prevent dementia.
Researchers found that overweight men with high blood pressure and high cholesterol in their 50s were more likely to develop dementia (related to blood vessel disease) in their late 70s. Vascular dementia is characterized by memory loss and other declines in mental function. The findings add another important reason to eat a healthy diet and get regular exercise.
Kalmijn S, Curb JD, Rodriguez BL, Yano K, Abbott RD. The association of body weight and anthropometry with mortality in elderly men: the Honolulu Heart Program.
Int J Obes Relat Metab Disord 1999;23:395-402. Presented at the American Academy of Neurology's 52nd Annual Meeting in San Diego.
ALTERNATIVES TO ANIMAL EXPERIMENTATION
Agricultural Research Service scientist Raymond Glahn has invented an "artificial gut" that promises to improve our understanding of iron availability in foods and supplements. Compared to similar tests performed on rats, the new method is less expensive, takes just three days instead of ten, is more relevant to humans, and spares animals' lives.
Scientists hope to use the device to identify foods with the highest iron absorption to assist developing countries where iron deficiency is still common.
Clogged Arteries Form Early in Life
If you think heart disease only happens to grandparents, think again. Autopsies performed on men aged 30 to 34 who died in accidents revealed that 20 percent of them had arteries with advanced plaques, the kind that can cause heart attack or stroke. Researchers looked at 760 coronary arteries and found advanced plaques in men as young as 15 and in women aged 30 to 34.
"We need to make sure our children are eating healthy foods, exercising, and not smoking," says Dr. Arthur Zeike, who worked on the study. Not surprisingly, people who were obese or who had high cholesterol were 2.5 times more likely to have advanced plaques. A diet rich in whole grains, vegetables, beans, and fruits is free of artery-clogging cholesterol and low in saturated fat.
McGill HC Jr, McMahan CA, Zieske AW, et al. Association of coronary heart disease risk factors with microscopic qualities of coronary atherosclerosis in youth. Circulation 2000;102:374-9.
© 2001, ARTVILLE
Active Women Have Lowered Risk for Stroke
Women who engage in moderate exercise, including walking, can reduce their risk of having a stroke, according to a new Harvard study. As part of the Nurses' Health Study, 72,488 female nurses aged 40 to 65 were followed from 1986, completing detailed physical activity questionnaires three times during the study. The most physically active women had only half the stroke risk of the least active ones. Exercise helps prevent ischemic strokes, caused by blockages in the arteries leading to the brain.
Playing sports, going to the gym, or simply walking—all proved effective for reducing risk. Of course, the longer and brisker the walks, the more protection they provided. This study showed that for every hour spent in moderate to vigorous physical activity each week, stroke risk was cut by roughly 10 percent—even for those women who had previously been inactive. Eating a diet rich in fruits and vegetables, not smoking, and maintaining a healthy body weight reduce stroke risk as well.
Hu F, Stampfer M, Colditz G, et al. Physical activity and risk of stroke in women. JAMA 2000;283:2961-7.
Dairy and Crohn's Disease
The dairy industry is again battling Johne's (pronounced yo-nees) disease, caused by a bacterium that interferes with digestion, lowers milk production, and eventually kills infected cows. But they are worried about more than lost profits. Research has linked the disease to the human intestinal disorder Crohn's disease. Earlier this year, Oregon State University and the USDA implemented a plan to carefully screen cow's blood and fecal samples for the bacteria, but this won't provide protection for average consumers.
Crohn's disease is a type of inflammation in the digestive tract. It often affects young people, causing fever, diarrhea, and pain after eating, sometimes leading to serious complications. In addition to genetic factors and bacterial infections, Crohn's disease is affected by diet. Many people with the illness have little fiber—specifically vegetables and fruits—and too much sugar in their diet. Boosting plant foods, including whole grain bread and brown rice, while avoiding sugar, white flour, and white rice has reduced patient hospitalizations in research studies.
Daily Exercise, Not Calcium, Is Key to Strong Bones
A long-term study of women found that bone density was significantly affected by how much exercise they got in their teen years, the time when girls develop 40 to 50 percent of their skeletal mass, while calcium intake made no difference.
Researchers at Penn State focused on hipbone density, a common site for fractures in women with osteoporosis. For six years, beginning at age 12, 81 girls were evaluated for dietary habits, sports activities, and participated in a calcium supplementation study. Consistent with past studies, intake of calcium above 900 milligrams per day (two glasses of milk) had no lasting effect on bone strength. Regular exercise did.
Lloyd T, Chinchilli VM, Johnson-Rollings N, Kieselhorst K, Eggli DF, Marcus R. Adult female hipbone density reflects teenage sports-exercise patterns but not teenage calcium intake. Pediatrics 2000;106:40-4.