Here is a probable explanation why low-calorie diets are beneficial for human health. Investigators have now found that higher metabolic rates indicate early natural mortality. This may be true because higher energy turnover accelerates aging in humans.
In order to ascertain whether higher metabolic rate is associated with aging in humans, experts studied energy expenditure, measured in a metabolic chamber over 24 hours and during rest predicts natural mortality. For this, a total of 652 non-diabetic healthy Pima Indian volunteers were put to test. The twenty four hour energy expenditure (24EE) was measured in 508 individuals, while resting metabolic rate (RMR) was measured in 384 individuals and 240 were subjected to both measurements on separate days.
“We found that higher endogenous metabolic rate that is how much energy the body uses for normal body functions, is a risk factor for earlier mortality. This increased metabolic rate may lead to earlier organ damage (in effect accelerated aging) possibly by accumulation of toxic substances produced with the increase in energy turnover. It is important to note that these data do not apply to exercise-related energy expenditure. This activity clearly has beneficial effects on human health,” said Reiner Jumpertz, MD, of the National Institute of Diabetes and Digestive and Kidney Diseases in Phoenix, Ariz., and lead author of the study.
Data for 24EE was gathered in a respiratory chamber between 1985 and 2006 with a mean follow-up time of 11.1 years. RMR, on the other hand, was assayed through an open-circuit respiratory hood system between 1982 and 2006 with a mean follow-up time of 15.4 years. In the course of the study, 27 volunteers died of natural causes. Authors observed that as energy expenditure increased, the threat for natural mortality also elevated. The study findings can seemingly aid in detecting some underlying mechanisms of human aging.
The study will be published in The Endocrine Society’s Journal of Clinical Endocrinology and Metabolism (JCEM).