A new study links lower calorie consumption to slowed aging and metabolism.
A recent study published in the journal Cell Metabolism found lowering calorie intake by just 15 percent—or 300 calories from the recommended daily guideline of 2,000—can slow aging and metabolism, leading to an overall healthier life and more positive mood.
The trial, called CALERIE (Comprehensive Assessment of the Long-Term Effect of Reducing Intake of Energy), examined people at a healthy weight and how restricting calories could affect their metabolism.
For two years, 53 men and women between the ages of 21 and 50 cut calories by 15 percent without following any particular diet. Calories were calculated specifically per individual with the goal to maintain weight. Though the study’s main purpose wasn’t weight loss, participants lost around 20 pounds on average.
Weight loss wasn’t the only side effect participants experienced—cutting calories also slowed down their metabolism and signs of aging. These changes were measured through regularly tracking participants' insulin and thyroid hormone levels.
Lead author Leanne M. Redman, associate professor of clinical sciences at Pennington Biomedical Research in Baton Rouge told Science Daily, "Restricting calories can slow your basal metabolism, and if byproducts of metabolism accelerate aging processes, calorie restriction sustained over several years may help to decrease risk for chronic disease and prolong life."
Another good sign? Cutting calories decreased subjects' systemic oxidative stress, which is tied to age-related neurological conditions like Alzheimer’s and Parkinson’s Disease.
Unpleasant side effects such as anemia, bone loss, or menstrual disorders typically associated with lower calorie intake were not found in this study. Though this is the first human study, previous studies that examined lower calorie diets were conducted on animals, and had found lower calories could lead to a longer life free of age-related disease, Wired reported.
The trial proves two major theories of human aging—the rate of living theory and the oxidative damage theory of aging. The rate of living theory suggests those who are most efficient at using energy will live the longest. The oxidative damage theory of aging indicates that damage to DNA, lipids, and proteins ultimately speeds up aging, according to the study.
The bottom line: This study is certainly compelling—but it was tested on a pretty small group of people for a short period of time, so more information and research is still needed. Until then, if you’re interested in cutting calories or trying a new diet, speak to your doctor first.