Once upon a time, living to a ripe old age was merely a possibility—if you were lucky. In truth, most of us didn't make it much beyond our reproductive years; as late as the 1890s, the average life expectancy in the U.S. was just around 45. But major advances in medicine and public health have expanded that to an average age of 78 (and that includes the recent 1-year drop due to COVID). The number of centenarians worldwide is predicted to climb to 3.7 million by 2050.
Researchers are now focusing less on the number of birthday candles on the cake and more on our "health span"—extending the number of years we can live free of the infirmities we've come to associate with aging, from a foggier memory and creaking joints to a weakened immune system and greater risk of cancer. Rather than chalking up those indignities to "just getting older," experts are looking at them as largely preventable and sometimes even reversible. "We don't have to accept misery and frailty as a 'natural' part of old age," says molecular biologist David Sinclair, Ph.D., co-director of the Paul F. Glenn Center for the Biology of Aging at Harvard Medical School and author of the provocatively titled Lifespan: Why We Age—and Why We Don't Have To. He believes that aging is primarily a function of problems reading the information—the genetic code—in our cells, and that epigenetic disruption is a key driver of that process.
Sinclair and other researchers are looking at ways of reprogramming those cells. Recent studies he has conducted in mice have shown that it's possible to restore cells' ability to read those genetic instructions, a process he likens to polishing the surface of a scratched CD to retrieve the stored information—the music—inside. In this case, Sinclair and his team were able to make the eye cells of old mice "younger" and reverse vision loss.
We're still years away from turning findings like this into a medical reality for us humans. "But we already have plenty of tools to help us maximize our vitality along the way," says EatingWell advisor David Katz, M.D., M.P.H., founding director of Yale University's Yale-Griffin Prevention Research Center and co-author of How to Eat: All Your Food and Diet Questions Answered. "The most important elements are lifestyle practices and having a healthy, supportive environment."
And when it comes to lifestyle habits, experts are pretty unanimous that what we choose to eat is central to aging well. An overall healthy diet that includes what Katz calls "the usual suspects"—fruits, vegetables and other plant-based, whole foods—is important. But the foods on the following pages are rich in compounds and nutrients that are particular anti-aging heroes. Other factors, such as regular exercise, sleep and stress management, are also associated with better aging.
Researchers at Harvard's T.H. Chan School of Public Health recently reviewed decades of data from more than 123,000 participants and concluded that those who maintained certain healthy patterns in adulthood—eating a good diet, exercising, keeping weight under control, not drinking too much alcohol or smoking—were able to add significantly to their projected life spans, with women gaining an average of 14 years and men picking up 12 years. Best of all: most of these habits are eminently doable, if not downright pleasurable (eating!). "We know what to do, and it's not that hard for most people," says Sinclair. "How you live now goes a long way to ensure you'll have a productive, healthy and enjoyable old age."
Here's what the science is showing, and which foods are worth putting on your plate.
What Is Aging, Anyway?
Time passes and we all get older, but it's clear that aging isn't just a function of time. Just attend a 20th or 40th high school reunion and you'll see a vivid tableau of how those decades seem to be kinder to some than others. Indeed, when it comes to the changes we associate with aging, the World Health Organization notes that "a gradual decrease in physical and mental capacity [and] a growing risk of disease ... are neither linear nor consistent, and they are only loosely associated with a person's age in years." Aging is actually a series of changes that occur at the molecular level in our bodies' cells, and experts say that how well we age is largely dependent on how healthy these microscopic body parts are.
When our cells divide and new ones replace the old ones, the DNA in their chromosomes is copied, supplying the vital instructions that make them function as they should. Capping the ends of our chromosomes are telomeres—-segments of DNA that help protect the precious genetic material inside and keep it intact during this process, akin to the way the aglet on the end of a shoelace prevents it from unraveling. As our cells replicate, telomeres tend to get smaller. Eventually, too-short telomeres send out chemical signals that trigger cells to stop dividing. Some die off, while others become senescent—less able to follow their genetic instructions, work properly and fend off disease. When senescent cells build up over time, our body's tissues start to age. Turning Back Time
The good news is that this process isn't all one way: Research has shown that telomeres can actually lengthen, thanks to an enzyme called telomerase, the availability of which controls whether these DNA caps shrink, hold steady or grow after certain cells divide. And lifestyle factors like a healthy diet can keep them robust. "The better we can preserve telomeres in healthy cells, the better our chances of a longer health span," explains molecular biologist Patricia Opresko, Ph.D., a professor of environmental and occupational health at the University of Pittsburgh and UPMC Hillman Cancer Center.
Proof of this concept was first demonstrated in a study led by Dean Ornish, M.D., a professor of medicine at the University of California, San Francisco and founder of the Preventive Medicine Research Institute (PMRI). Ornish's plant-based diet and lifestyle program, which includes things like moderate daily exercise and stress management, is best known for reducing—and sometimes reversing—the course of heart disease, but this research looked at prostate cancer patients. His team discovered that disease progression was significantly slower among those on the Ornish plan. And a follow-up study in another group of men with early-stage prostate cancer found that those who adhered most closely to the regimen had, on average, a 10% increase in the length of their telomeres after 5 years. By contrast, a control group that didn't follow the diet and lifestyle interventions had telomeres that became 3% shorter over the same period. The findings were some of the first to show "a very promising potential for individuals to change their lifestyle and have more control over how they age," notes Carra Richling, RD, senior registered dietitian at PMRI.
The Food Factor
A major contributor to inflammaging is oxidative stress, or the production of so-called "free radicals" in the body that damage cells, including our telomeres. Research in Opresko's lab found that high levels of oxidative stress can speed up the shortening of telomeres. But a plant-rich diet that includes plenty of vegetables, fruits and whole grains can "protect and preserve your telomeres in a natural and healthy way," Opresko explains. The antioxidants they contain act as an off switch to the oxidation-inflammation process by neutralizing free radicals and breaking the chain of reactions that leads to cell damage. That may be one reason why the oft-lauded, plant-centric Mediterranean diet and DASH eating patterns have been tied to both lower rates of inflammation and longer telomere length. These eating patterns also provide plenty of soluble and insoluble fiber, which helps support a healthy microbiome—another key way to keep inflammation at bay.
Equally important as what you eat is what you don't, including red and processed meats, like sausage and cold cuts. Both are sources of pro-inflammatory compounds and have high amounts of saturated fat, which lead to the production of chemicals that can tip the immune system's balance in an inflammatory direction, says Katz.
Other inflammation stokers are foods with refined carbohydrates, such as white bread and pasta, and added sugars. They cause insulin spikes that negatively affect the immune system. Sugary sodas are especially potent inflammagers: an American Journal of Public Health study of 5,300 participants found a significant link between soda consumption and shorter telomere length—and that each daily 8-ounce serving was associated with nearly 2 extra years of cellular aging.
Recent studies also implicate ultra-processed foods, like chips and fast food, with higher levels of inflammation and shorter telomere lengths. A Spanish study of 886 seniors showed that those who consumed the most ultra-processed foods (3 or more servings a day) had almost double the odds of having short telomeres compared with those who ate the least (less than 2 daily servings). Why? These foods deliver pro-inflammatory nutrients we already get too much of—salt, added sugars, refined carbs and unhealthy fats.
Sticking to a more plant-based, whole-food-rich diet is a recommendation we've all certainly heard before. But that is the point, experts say. It's a proven way to live better now, and it also happens to provide the best insurance for a longer and happier health span.
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