Calorie restriction refers to a dietary approach that reduces calories, while maintaining appropriate nutrient and vitamin levels. The overall aim of such a regimen is on extending life-expectancy. The definition of ‘low calories’ has no universal meaning and it is tailored to individuals. The diet is based on research that has taken place over the past few decades on different animals, where a lower calorie intake has seemingly extended life-expectancy, at least in terms of lower cellular ageing. The types of animals studied include fish, rodents and dogs. However, the results of such studies are not been universal in their findings and supporting data, especially in relation to applying the diet humans, has been contested by scientists.
A new study seeks to offer further support in relation to calorie reduction leading to a slower rate of biological ageing, and this time it is based on a study of monkeys. The study comes from two research centers – University of Wisconsin-Madison and one from the National Institute on Aging – who co-operated together to pool their respective findings.
The two research bases worked together to analyze data collected over many years, relating to 200 monkeys. Data from the University of Wisconsin-Madison indicated benefits with the restricted diet in relation to survival and reductions in cancer, cardiovascular disease, and insulin resistance; and the National Institute on Aging study, in contrast, showed no significant improvement in survival, although the monkeys tended to be healthier than others who were not given a restricted diet.
Examining why the study results were so very different, the researchers noted that the monkeys in the two studies were given low calorie diets at different ages. A re-review showed that eating less was beneficial in adult and older primates. It was also found that the level of calories consumed was important. The National Institute on Aging monkeys eat less than the monkeys who were housed at Wisconsin. This inferred that relatively small differences in food intake could meaningfully affect aging and health.
The third finding related to the type of diet. The National Institute on Aging moneys were given a diet rich in ate naturally sourced foods, whereas the Wisconsin ones eat processed food with higher sugar content. This indicates the type of food is important and not just its calorific value.
Based on this, the two research centers conclude that caloric restriction does affect aging. However, there are a number of key factors to consider. It should be noted that the research did not involve human subjects and no claim is made about any benefits or otherwise to people.
The research has been filed in the journal Natural Communications under the title “Caloric restriction improves health and survival of rhesus monkeys.”
