(page 2 of 3)
What do you hope to find?
That there might be differences between the number of leptin receptors in the two species.
In your class on aging, you teach that aging and eating are closely related. What’s the connection?
Insulin is the hormone that is released when you eat carbohydrates; it allows glucose to be taken up into your cells. Insulin and leptin are very closely related. It turns out that insulin, which is released when you eat, is also key to the process of aging. To put it very simply, it looks like when you stimulate insulin, you stimulate aging.
Do you think science can extend the human lifespan?
Even though modern medicine has made people stay healthier longer and live longer, the actual lifespan of humans hasn’t changed—no one can live past 120. But recently scientists have proven that caloric restriction can make an organism live longer. In experiments, yeast and mice that consume very few calories live up to 50% longer than their normal projected lifespan, and primates on caloric restriction seem much younger and more vigorous than their normally fed peers. Also, there was an experiment in which they fed mice huge quantities of resveratrol, a chemical found in red wine, and they lived much longer.
So we shouldn’t eat much but should drink a lot of red wine?
That’s one way of looking at it. But you’d have to drink something like 100 liters a day to achieve that effect. The goal is to be able to manipulate these biochemical processes without massive quantities of resveratrol.
How does caloric restriction work?
It creates a hostile environment for the body. The body can’t get enough food, so it puts everything on hold, including aging, in the hopes that it will survive this bad period and then reproduce when conditions improve. Anything that stresses you in that way—exercise, for example—can help you live longer, though of course exercise isn’t nearly as extreme, or effective, as caloric restriction.
What happens if researchers unlock the secrets of aging, and we’re able to make everyone live for 140 years?
The social implications of longevity work are complex. A lot of people think this kind or research is suspect because of its potential effect on society. But the people who study longevity are interested not so much in the practical applications but in the intellectual puzzle of it—aging is an intriguing and elusive issue, and we want to understand how it works. Extending the lifespan isn’t the goal of my research. It seems selfish to do this work with the goal of making everyone live longer, without taking into account the long-term implications of increased longevity—which I’m not sure are desirable.
So other than caloric restriction, are there any weight-loss plans that work?
Your metabolism works hard to keep your weight at a set point. The only way to lose weight permanently is to change that set point. There is some research that shows that if you diet for a long time, or if you exercise a lot, your set point can change, and then it won’t be so hard to stay at your desired weight. But it’s not easy to do.