Scientists at the Gladstone Institutes have identified a novel mechanism by which a type of low-carb, low-calorie diet — called a “ketogenic diet” — could delay the effects of aging: the compound β-hydroxybutyrate (βOHB), that is generated during a prolonged low-calorie or ketogenic diet.
While ketone bodies such as βOHB can be toxic when present at very high concentrations in people with diseases such as Type I diabetes, researchers in the laboratory of Gladstone Senior Investigator Eric Verdin, MD found that at lower concentrations, βOHB actually helps protect cells from “oxidative stress” — which occurs as certain molecules build to toxic levels in the body and contributes to the aging process.
This fundamental discovery reveals how such a diet could slow the aging process and may one day allow scientists to better treat or prevent age-related diseases, including heart disease, Alzheimer’s disease, and many forms of cancer.
“Over the years, studies have found that restricting calories slows aging and increases longevity — however the mechanism of this effect has remained elusive,” Dr. Verdin said. He directs the Center for HIV & Aging at Gladstone and is also a professor at the University of California, San Francisco, with which Gladstone is affiliated. “Here, we find that βOHB — the body’s major source of energy during exercise or fasting — blocks a class of enzymes that would otherwise promote oxidative stress, thus protecting cells from aging,” he said.
Oxidative stress occurs as cells use oxygen to produce energy, but this activity also releases other potentially toxic molecules, known as free radicals. As cells age, they become less effective in clearing these free radicals — leading to cell damage, oxidative stress, and the effects of aging.