How does a limited diet change how your body ages? Dr. Oz says when you restrict your calories, the body understands that it doesn't have any resources to waste.
"The body gets really efficient," he says. "You turn on this new chemical pathway we never knew existed called the sirtuin pathway. What it tells you is don't make more babies because you don't have the excess abundant energy to do that—just live longer."
The body's cells also benefit when calories are limited. "We don't have toxic waste products coming out of our energy cells," Dr. Oz says. "So we're actually able to get the individual cell lines to live longer."