Living Longer Diet - Diet with Fruits and Vegetables

It's hard to get through your first cup of morning coffee without reading a headline about food. Eat blueberries! Such antioxidant-rich foods will clear your arteries and help prevent the buildup of Alzheimer's plaque in your brain. Add in a cup of green tea in the morning and swish down an ounce or two of dark chocolate with a glass of red wine in the evening and you will be nicely tanked up on healthy fuel for the day.

Or will you? Almost every day, it seems, new studies emerge on the antiaging properties of various foods. One day, soy is good; the next, we find out soy's health benefits may have been oversold. To add to the confusion, this year The Journal of the American Medical Association (JAMA) published a study that found caloric restriction—eating about 25 percent less than normal—could extend your life.

So which headlines should we believe? And why should we believe them? The answers lie in research that shows exactly how various foods work at the cellular level. In particular, antioxidant-rich fruits and vegetables are emerging as powerful medicine in the fight against cellular aging.

Here's how it works. In the normal process of metabolism, cells produce unstable oxygen molecules—called free radicals—that damage cells. Worse still, the older we get, the more free radicals we produce. Recent studies suggest that the havoc free radicals wreak "plays a central role in virtually every age-related disease, including cardiovascular diseases such as stroke and atherosclerosis, Parkinson's disease, Alzheimer's, and type 2 diabetes," says Mark Mattson, Ph.D., chief of the Laboratory of Neurosciences at the National Institute on Aging at the National Institutes of Health.

It sounds pretty grim, but in this battle there are, thankfully, superheroes. Enter the vibrant world of antioxidants—substances that bind with free radicals and inhibit them from damaging cells. They are abundant in the most colorful fruits and vegetables, including spinach, broccoli, spirulina (blue-green algae), red apples, cranberries, blueberries, cherries, and grapes, as well as in chocolate and red wine. When you hear doctors say that eating five helpings of fruits and vegetables a day is good for you, antioxidants are the main reason. In the past five years an impressive body of research has emerged showing how antioxidants may protect the body and brain against the ravages of aging.

Paula Bickford, Ph.D., a researcher at the University of South Florida Center of Excellence for Aging and Brain Repair, is particularly interested in the role of antioxidants in brain health. The brain is a good place to study the benefits of antioxidants, says Bickford, because it has one of the highest percentages of fats of any organ in the body, and it is in our fats that free radicals inflict much of their damage.

As we age, "communications between neurons become damaged, kind of like what happened to the Tin Man in The Wizard of Oz," she explains. "Oxidative damage caused the Tin Man to grow rusty—until Dorothy came along and oiled him." Similarly, antioxidants help to "regrease the lines of communication" in the cells in our brain, says Bickford.

To measure how the communication between cells was affected when groups of rats ate different diets, Bickford and her colleagues placed electrodes in the brains of 20-month-old rats—the equivalent of 60-year-old humans. She then fed one group of rats a diet supplemented with spirulina, another with apples, and a third with cucumbers, which lack the antioxidant qualities of spirulina and apples. Bickford and her colleagues were surprised by the robustness with which "both the spirulina and apple groups demonstrated improved neuron function in the brain, a suppression of inflammatory substances in the brain, and a decrease in oxidative damage." By contrast, there was no improvement in rats fed a diet containing cucumbers. Bickford, who calls the findings "dramatic," reproduced her results in another study, in which rats fed a spinach-rich diet had a reversal in the loss of learning ability that occurs with age.

Most recently, Bickford examined whether eating a diet high in antioxidant-rich spinach and blueberries makes a difference in lab animals suffering from stroke and Parkinson's. "We've seen very positive effects with both of these diseases, as well," she says. "We believe that antioxidants can help people either to delay the onset or to slow the progression of a range of diseases that we tend to get as we age."

Tempting though it may be now to go out and gorge on antioxidant-rich dark chocolate, resist the urge. The hottest discovery in the search to find the fountain of youth through the foods we eat is to—gulp!—eat a lot less of them. A 2006 article in JAMA caused a stir by announcing that in both men and women, caloric restriction—as spartan as 890 calories a day—resulted in a decrease in fasting insulin levels and body temperature, two biomarkers of longevity. Why? Because restricting calories also helps to eliminate those nefarious free radicals. Mattson explains: "When you overeat and more energy comes into the cells than you burn off by being active, you are going to have more excess free radicals roaming around." Still, he advises, don't panic over the idea of having to subsist on 890 calories a day. Mattson, who calls such a diet "starvation," believes we can all gain the benefits of healthy eating with a lot less pain.

Richard Miller, M.D., Ph.D., a researcher and professor of pathology at the University of Michigan, agrees. He has spent the last 20 years studying the ways in which dietary and genetic changes can slow the aging process. The research has shown that mice, rats, and monkeys that have undergone severe caloric restriction demonstrate all kinds of mental and physical benefits such as better mental function, less joint disease, and even fewer cases of cataracts. But it's unrealistic to try to replicate that in humans. "To copy what's happening in the lab, a man weighing 200 pounds would have to decrease his caloric intake by 40 percent for life, which would put him at about 120 pounds," Miller explains. "That's just not tenable."

Instead, Mattson and Miller advocate a more moderate approach. According to the Centers for Disease Control and Prevention, the average man in the United States consumes about 2,475 calories a day. That's roughly 500 more, on average, than he really needs. Likewise, the average American woman consumes 1,833 calories, yet probably needs only about 1,600. One way to ratchet down your caloric consumption would be to follow this simple equation: men should aim for about 500 calories at both breakfast and lunch, while women should strive for about 300 at each meal. Both sexes can then shoot for 1,000 calories at dinner.

Bickford, who prefers to think of caloric restriction as caloric selection, underscores the importance of getting as much of your caloric intake as you can not only from antioxidant-rich fruits and vegetables but also from nuts and flaxseed, which are loaded with vitamin E and omega-3 and omega-6 fatty acids. In fact, Bickford takes a page out of her own lab studies and starts her day with an antioxidant smoothie. You can try it at home by blending together one cup of frozen blueberries with half a tablespoon of spirulina (available in any health food store), half a cup of nonfat plain yogurt, one teaspoon of ground flaxseed, one tablespoon of almond butter or a half-handful of almonds, and a dash of soy milk. Consider what's in that blender as a gas tank full of high-antioxidant fuel for the day.

Of course, one can't help but ask: what's the fun of living to 102 if you're subsisting on spirulina shakes? Not to worry. If you splurge on a stack of pancakes with eggs, bacon, and sausage—packing in 2,000 calories before 10 a.m.—you can always take heart in new data about to emerge from Mattson's lab, which show that periodic fasting—skipping a meal here and there—can also help to eliminate free radicals quite beautifully. "From an evolutionary standpoint we just aren't used to constant access to food," he explains. "Our bodies are used to going days without eating anything. Yet all of a sudden, we are taking in calories all day long."

In other words, we have gone from thousands of years of intermittently restricting our calories and eating a high-antioxidant diet to, in the past century, constantly eating a low-antioxidant diet. And that means more free radicals and more disease. So indulge in the pancakes or the cheese steak, but not both. Then skip a couple of meals and make your next one an all-out antioxidant feast. It may be counter to the don't-skip-meals philosophy our mothers all taught us; yet as it turns out, Mother Nature just might know better.

By Donna Jackson Nakazawa