The Benefits of the Blueberry
Popeye--and probably your mother--always said that spinach is good for you. New research suggests that the cartoon sailor man and Mom were right, but that your health may have benefited even more by eating blueberries, which also taste better.
Researchers from the U.S. Department of Agriculture’s Human Nutrition Research Center at Tufts University fed extracts of blueberries, strawberries or spinach to 19-month-old rats, whose age is roughly equivalent to 65- to 70-year-old humans, and compared their health with that of rats receiving no supplements.
They reported in Wednesday’s Journal of Neuroscience that all the animals receiving supplements showed improvements in short-term memory compared with those who received none. But the animals receiving the blueberry extracts also showed distinct improvements in balance and coordination.
Blueberries, strawberries and spinach contain naturally occurring antioxidants, which block the destructive effects of highly reactive forms of oxygen called free radicals. Such radicals are thought to play a role in aging, cancer and other diseases.
“The exciting finding from this study is the potential reversal of some age-related impairments in both memory and motor coordination,” said Molly Wagster of the National Institute on Aging. “The investigators were able to produce a notable improvement within a relatively short period of time. A next important step in the research will be to see if the improvements are long-lasting.”
Beta Carotene Doesn’t Reduce Risk of Diabetes
But there is disappointing news about another antioxidant called beta carotene. Based on studies with fruits and vegetables, researchers had believed that beta carotene supplements would reduce the risk of developing type 2 diabetes, but a new study says that is not the case.
The results come from the ongoing Physicians Health Study being conducted at Brigham and Women’s Hospital in Boston. The study has followed 22,071 male physicians between the ages of 40 and 84 since 1982.
Dr. Simim Liu and colleagues reported in Wednesday’s Journal of the American Medical Assn. that the number of cases of type 2 diabetes were virtually identical in groups receiving beta carotene supplements and in those not receiving them. Type 2 diabetes is the most common form of the disease, afflicting an estimated 15 million Americans, most of them over the age of 45.
Soaking in Hot Water Can Lower Blood Sugar
More encouraging news about diabetes occurs in a report in Thursday’s New England Journal of Medicine. A preliminary study from the McKee Medical Center in Loveland, Colo., suggests that soaking in a hot tub for 30 minutes per day over a three-week period can reduce blood sugar levels by 13%. The treatment worked so well for one of the eight volunteers that he had to reduce the amount of insulin he was taking by 18% to avoid having his blood sugar level fall too low.
The idea is not completely out of left field, argues author Dr. Philip Hooper. Previous research has shown that exercise reduces the need for insulin, and relaxation in the hot tub provides a similar effect, he said. It does not, however, help reduce weight.
Systolic Pressure Can Predict Risk
Physicians have traditionally relied primarily on diastolic blood pressure--the second number in a blood pressure such as 120/80--in determining whether a patient is hypertensive; that number correlates well with the risk of heart attack and stroke in young people. For older people, however, a new study suggests that systolic pressure, the first number, is a more important predictor of risk.
Systolic pressure measures the force blood exerts on the artery walls when the heart beats. Diastolic pressure measures the force between heartbeats. Hypertension is usually diagnosed when systolic blood pressure is 140 millimeters of mercury or higher or the diastolic blood pressure is 90 millimeters of mercury or higher.
Researchers from the National Heart, Lung and Blood Institute’s Framingham Heart Study examined nearly 5,000 untreated men and women, average age 58, and determined that their systolic blood pressure was a much better predictor of risk than the diastolic pressure.
An estimated 50 million Americans have hypertension, and only 68% of them are aware of it. About 54% are being treated for the problem, but only 27% have it under control, according to the institute.
High Blood Pressure May Cause Bone Loss
An unsuspected outcome of high blood pressure may be increased bone loss in the elderly, according to British researchers. Hypertension has previously been associated with abnormalities in calcium metabolism, but a new study in Saturday’s Lancet is the first human study on the link to osteoporosis.
Dr. Francesco P. Cappuccio from St. George’s Hospital Medical School and his colleagues at the London School of Hygiene and Tropical Medicine and the University of Pittsburgh studied 3,676 elderly white American women with a mean age of 73 years. They found that the yearly rate of bone loss was 68% higher in women in the highest blood pressure group than among those with the lowest pressures. Studies in mice suggest that salt plays a role in this process, and Cappuccio suggested that reduced salt intake could both reduce blood pressure and combat osteoporosis.
Mutated Gene Plays Role in Prostate Cancer
African American and Latino men who carry a simple genetic mutation have about five times the normal risk of developing prostate cancer, according to USC researchers. The results also suggest why one of the most promising drugs for prostate cancer, Proscar, fails in many men.
An estimated 179,000 American men will be diagnosed with prostate cancer this year and 40,000 will die from it. The incidence is substantially higher in African American men than in whites and the death rate is twice as high.
Molecular biologist Juergen Reichardt and his colleagues report in Saturday’s Lancet that the defect occurs in an enzyme called steroid 5-alpha-reductase, which controls the conversion of testosterone to dihydrotestosterone, or DHT, a very potent male hormone. When the enzyme is mutated, it produces much higher levels of DHT, which accelerates growth of the prostate.
Less than 1% of healthy men carry this mutated gene, but as many as 10% of African Americans and Latinos with prostate cancer do. The team also found that men with the mutated gene do not respond well to Proscar and should be given other treatments.
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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com.
