One of the keys to a long life is to eat less - at least for laboratory rats and fruit flies. Now a study of primates, published in this month of American Journal of Physiology suggests that reducing caloric intake to 30% below the level regarded as normal may benefit the heart. Rhesus monkeys on the low-calorie diet have higher levels of cholesterol and triglycerides lowest levels of 'good', the two that guard against heart disease and stroke in humans. The advantage is greater for young people of middle-aged monkeys and shrinks in old age.
For the last decade, molecular biologist George Roth of the National Institute on Aging has been studying the effects of calorie restriction on rhesus monkeys. All 60 monkeys given the same diet, but half are only allowed 70% of the calories normally consumed as a monkey. In previous research, Roth and colleagues have slightly lower blood pressure, improved glucose tolerance and insulin sensitivity (which means that the animals are less likely to develop diabetes), and lower body temperatures in the low-cal group. "What we think is that animals that are restricted are shifting their metabolic strategy of growth and reproduction in a life care strategy," said Roth.
In this document, Roth announcement of results relative to compounds surveillance levels that influence cardiovascular health. the monkeys who ate less had higher levels of normal HDL2B, a type of high-density lipoproteins and protective cholesterol. the largest increase (83%) was for the youngest group of monkeys - 10 years - and the least (16%) for older monkeys, until the age of 28. the levels of people of old age means. about 13 to 15 years in triglycerides were 41% lower than the monkeys on the full meal plan calories. juvenile levels were 11% below normal, and levels were 8% higher than normal for the older monkeys.
"There is solid information," said Richard Weindruch, a gerontologist at the University of Wisconsin, Madison. The next step, says endocrinologist William Cefalu of Bowman Gray School of Medicine in Winston-Salem, North Carolina, is to relate the results to disease. Indeed, the monkeys will soon be tested to determine if they develop heart disease and to what degree, Roth said.
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