No Meat for the Middle-Aged: Study Shows Risk of High-Protein Diet
“Wait until you’re older” is an admonishment you expect as a child when asking for a parent’s permission, but a new study suggests it might apply to your protein intake, too. Per a study published in the journal Cell Metabolism, researchers found that a high-protein diet increased mortality rates for people between the ages of 50 and 65 but was then associated with lower rates in people older than 66. Using findings from self-reported data, the researchers confirmed aspects of their results in mice.
Insulin-like growth factor 1 (IGF-1) is a protein in the body that aids in development. When it is deficient in humans and mice, researchers have noted a reduction in age-related diseases. Protein intake impacts its activity, with less protein corresponding to less activity. Based on this, the researchers wanted to undertake a study to evaluate potential links between protein and mortality.
“There’s a misconception that because we all eat, understanding nutrition is simple. But the question is not whether a certain diet allows you to do well for three days, but can it help you survive to be 100?” Valter Longo, the Edna M. Jones professor of biogerontology at the University of Southern California Davis School of Gerontology and director of the USC Longevity Institute, and an author of the study, said in a press release.
The researchers based their study on the NHANES III, the third National Health and Nutrition Examination Survey. From this self-reported data came a cohort of 6,381 adults in the U.S. over 50 years old. The average age was 65, and most people consumed 1,823 calories per day. The majority had 51 percent of their calories come from carbohydrates, 33 percent from fat, and 16 percent from protein, 11 percent of which was derived from animals.