The compound the mice ate resulted in their muscles becoming very toned, as if they’d been exercising. Inflammation, a key factor in many disease processes, was drastically reduced. Insulin resistance also declined dramatically and the mice had much more energy overall. Researchers say that what happened to the mice could be compared to a 60 year old person suddenly having the muscle tone and energy of someone in his or her 20s.
What’s more, say the researchers, these stunning results were realized within just one week’s time. The compound raises the level of a naturally occurring substance in the human body called nicotinamide adenine dinucleotide. This substance decreases as people age, although those who follow a healthy diet and get plenty of exercise do not suffer the same level of reduction in the substance as do people who do not exercise. This may explain why people who remain fit into their senior years often enjoy better health than others.

http://www.newsforage.com/2014/03/aging-successfully-reversed-in-mice.html