In a study of Labrador retriever dogs, those fed a calorie-restricted diet showed different lifelong patterns relating to energy metabolism and the activities of their gut microbes and lived almost two years longer than similar dogs given a slightly higher-calorie diet.
The study, which followed 24 dogs lifelong, is scheduled for the May 4 issue of ACS? Journal of Proteome Research, a monthly publication.
Imperial College London?s Jeremy K. Nicholson and colleagues from Nestl? and Nestl? Purina Research centers in Switzerland and the United States point out that previous studies on a range of animals have established calorie restriction as a proven method for extending the lifespan of animals. Those studies, however, have not explained how calorie restriction works.
The new study aimed at improving knowledge of the metabolic effects of caloric restriction suggests that some of the important beneficial changes may relate to the activities of the symbiotic bacteria that live in the intestinal tract. Those microbes produce a range of biochemicals that may influence disease processes and alter energy metabolism in the host organism. Researchers paired 24 dogs, with one dog in each pair given 25 percent less food than the other. Those with a restricted intake of calories lived, on average, about 1.8 years longer than those with a greater intake. Researchers noted that the study?s main goal was to help develop diets that keep pet animals alive and healthy for as long as possible, but that the findings may be relevant to human dietary changes and obesity.
“Metabonomic Investigations of Aging and Calorie Restriction in a Life-Long Dog Study”