With Dec. 31 drawing near, many well-meaning people will make promises to themselves that will inevitably be unkept over the following 12 months: New Year’s resolutions.
It’s a shame, since most of those resolutions revolve around things that should make us better in one way or another: work out, learn new things, support worthy causes. But what if there was another approach? What if, instead of resolving to do more with your life, you did something to give you more life itself? Could you, in effect, resolve to live longer so you have more years to walk those extra miles, write those novels, master those yoga poses?
The short answer is yes, says Harvard researcher David A. Sinclair, who spent a quarter-century studying what makes people live longer. His new book “Lifespan: Why We Age—and Why We Don’t Have To” came out in September from Simon & Schuster and hit the New York Times best seller list.
“The most surprising thing is that only 20 percent of our longevity, our health in our old age, is genetically determined,” says Sinclair, the co-director of the Paul F. Glenn Center for the Biology of Aging Research and a professor of genetics at the Blavatnik Institute of the Harvard Medical School. “The rest of it—80 percent of it—is in our hands, in how we live our lives.”
So … what’s his number one tip on how to add years to your life, so you can add life to your years?
“If there’s only one thing I can say after reading thousands of papers and researching this for 25 years,” says Sinclair, “it would be to eat less often.
“I don’t want to offend any restaurateurs because I love dinner,” he hastily adds, “but I skip breakfast and I have a very late lunch.”
Specifically, what was found over many different studies and supported with clinical research in Sinclair’s lab was that it’s not so important what you eat but when you eat. For instance, scientists with the National Institutes of Health fed different groups of mice a whole range of diets. What they ate made no difference in their lifespan. Instead, it was when they fed the mice that had the impact.
“If we only gave them food for a two-hour period a day, they lived the longest,” Sinclair says. “But they ate a lot of it in those two hours.”
Sinclair still urges people to “eat well” and not fret over the exact makeup of their diet. Want to have a little meat, or indulge in a special dessert? That’s okay, he says—the amount and timing of what you eat appears to be more important than the exact mix of carbohydrates, proteins, and fats.
“I try to eat more of a rabbit’s diet than a lion’s diet. But I steal a lot of meat, I steal a dessert, and it doesn’t count if you’re stealing, right?” he says, laughing.
The other standout component of longevity from all of this research is that, yes, exercise plays an important role, but in a surprising way.
“The best way to turn on longevity genes is to be out of breath for as little as 10 minutes a day every couple of days,” Sinclair explains. “It’s surprising how easy it is.”
This kind of exercise turns on the same “genetic pathway protectors” as fasting or being hungry. In other words, he says, a little bit of adversity is good for your body.
“Your body will only turn on the survival program when it has a threat, otherwise it’s not going to waste the energy,” says Sinclair. “The goal is to trick the body into thinking times are going to be tough.”
For his part, Sinclair accomplishes this by spending a couple hours in the gym every weekend doing weights (“That’s important, because it increases metabolism so you can enjoy more food.”) as well as time on a treadmill or stair-climber.
Plus, he adds, it looks like a trip to the sauna followed by a cold plunge “might activate the same longevity genes as exercise and fasting,” so he does that at the gym every week, too.
In the end, it seems that at least some of those reliably recycled resolutions—the ones about improving your diet and getting more exercise—are the exact same things that will help increase your longevity if you approach them in the right way. But that won’t mean it’s any easier to keep them as it was before you knew the science, acknowledges Sinclair.
“You gotta fight against what your body is telling you to go do,” he says. “Your body wants to sit down, your body wants to eat. And that’s great when you’re young. But if you want to make it into old age, you have to put your body into adversity, and it will pay dividends later in life.
“Hormesis is the scientific word for that,” Sinclair adds. “What doesn’t kill you will make you live longer.”
David A. Sinclair’s book “Lifespan” can be purchased at Porter Square Books and the Harvard Book Store, or borrowed from the Cambridge Public Library. For information about his upcoming book tour, follow @DavidASinclair on Twitter.
This story appears in the Nov/Dec print issue of Scout Cambridge, which is available for free at more than 220 drop spots throughout Cambridge (and just beyond its borders) or by subscription.
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