Lifespan: Why We Age—and Why We Don't Have To

by David A. Sinclair

When we investigate places like this, and as we seek to apply research about fasting to our modern lives, we find that there are scores of ways to calorie restrict that are sustainable, and many take the form of what has come to be known as periodic fasting—not being hungry all the time but using hunger some of the time to engage our survival circuit. Over time, some of these ways of limiting food will prove to be more effective than others. A popular method is to skip breakfast and have a late lunch (the 16:8 diet). Another is to eat 75 percent fewer calories for two days a week (the 5:2 diet). If you’re a bit more adventurous, you can try skipping food a couple of days a week (Eat Stop Eat), or as the health pundit Peter Attia does, go hungry for an entire week every quarter. The permutations of these various models for extending life and health are being worked out in animals and will be worked out in people, too. The short-term studies are promising. I suspect the long-term research will be, too. In the meantime, however, almost any periodic fasting diet that does not result in malnutrition is likely to put your longevity genes to work in ways that will result in a longer, healthier life.