Researchers at Washington University School of Medicine in Saint Louis are launching a long-term study to see if eating a low-calorie or a nutritionally balanced diet can extend human life span.
Luigi Fontana, investigator at the “Instituto Superiore di Sanita” in Rome and assistant professor of medicine at Washington University, says in an editorial in “Journal of the American Medical Association” that calorie restricted diets can influence the process of aging and suggest some ways to modify its effects. Early on this year, in January, Fontana and his mates found out that after around six years of calorie restriction diet people’s hearts functioned like the hearts of much younger people. Another team, from the “Pennington Biomedical Research Center” at “Louisiana State University” reported that six months of calorie restriction diet reduce fasting insulin and body temperature, which are two key markers of aging.
These facts have been known more than ten years ago, when several researchers demonstrated that consistent and stringent calorie restriction diet increased the maximum lifespan by about 30 percent in mice and rats, and also protected them against cancer and atherosclerosis. Yet, human study has been very difficult to conduct because the calorie restriction diet requires a very strict diet, to keep the total number of calories low as well as to ensure that people consume the recommended balance of nutrients. Thus, some people from the Calorie Restriction Society limit their caloric intake, hoping that they will improve their health and extend their lives. Fontana conducted extended research with the people from this group and reported last time in the January issue of the “Journal of American College of Cardiology” that the hearts of people that are following a calorie restriction diet are more elastic than those of gender and age matched control subjects. Furthermore, their hearts were able to relax in a similar way of younger people between beats.
The team from “Pennington Biomedical Research Center” reported a six-moth study of women and men aged between 25 and 50 who adopted a calorie restriction diet that lowered their caloric intake by 25%. The study, known as CALERIE (Comprehensive Assessment of the Long Term effects of Reducing Intake of Energy), found out that all the subjects who increased their exercises or dieted lost body-fat and weight. Amazingly, the subjects on a calorie restriction diet lowered core body temperature and fasting insulin levels. Also, after the study the subjects had less oxidative damage to their DNA, which is a marker at the cellular and biochemical levels. A second phase of the CALERIE study will be launched by Holloszy and Fontana, this time over the course of two years.
--Reproduced by Ramona Misaila from an article in Science Daily