The key to living longer may involve calorie deprivation, a new study suggests. But humans might able to find the same effects in a pill form.

Laboratory animals that are fed very low-calorie diets live longer. These findings might help scientists develop a pill that leads to longevity, say researchers at Harvard Medical School, Cornell University and the U.S. National Institutes of Health.

Researchers discovered that fasting, or limiting caloric intake, raises levels of certain proteins that activate two specific genes in the cell mitochondria. The two genes may be potential drug targets in an effort to combat diseases associated with aging and to slow down the aging process, they said. The study was published in the journal Cell.