1939—Caloric Restriction Increases Lifespan

The first study identifying a method to extend lifespan was published in 1939. This landmark study by McCay, Crowell, and Maynard found that caloric restriction (a diet that meets nutritional requirements but provides greatly reduced calories) in rats could increase their average lifespan. The biological mechanism of caloric restriction, and whether it works in humans, remains an important question in research on aging today.