Per gram of tissue, the brain produces more free radicals — highly reactive molecules that can contribute to cell damage, especially in the brain’s delicate fat tissue — than any other organ. Some scientists suspect damage from free radicals is one of the biggest culprits in the memory loss associated with aging. “Fat is much more susceptible to free-radical damage than other types of tissue,” says Perlmutter. “And its repair mechanisms don’t work as well.”
Luckily, antioxidants are the brain’s cleanup crew. Found primarily in fruits and vegetables, antioxidants work around the clock to scrub the body clean of free radicals. Numerous studies show that people who eat the most fruits and veggies throughout life are less likely to suffer from dementia later on.
The brain needs sugar (glucose) for energy, but it likes a nice, steady, natural supply — the kind you get from the sugars found in fruits and veggies — not the refined sugars heaped into an energy drink or a candy bar. “It’s not good for the brain to swing wildly from one blood-sugar extreme to another,” says Carol Lippa, MD, neurologist and director of the Memory Disorders Center at the Drexel University College of Medicine in Philadelphia. “Sugar molecules slip into the brain and other organs easily, so you want to be careful not to overload your system.”
In a 2006 double-blind study at Loughborough University in Leicestershire, England, researchers fed sleep-deprived participants a light lunch, then gave them 8 ounces of either an energy drink containing high levels of sugar and some caffeine or a similar-tasting control drink that had no caffeine and no sugar. Ten minutes later, each participant took three 30-minute tests that measured reaction time. They repeated the design a week later, but provided each person with the opposite drink.
The results? Not only did the caffeine and glucose-laden drinks not counteract feelings of sleepiness, they actually made the participants’ reaction times worse.
What’s more, when high-sugar foods such as colas and processed foods send a tsunami of glucose crashing into the bloodstream, those surges eventually overwhelm the body’s ability to restore balance. When that happens, you become insulin resistant (your body no longer responds to insulin), so your blood sugar rises and type 2 diabetes develops. Studies link insulin resistance to higher rates of vascular dementia and Alzheimer’s disease.
Another deleterious side effect of insulin resistance is inflammation. When the body’s systems are out of whack, the immune system goes into overdrive trying to fix the problem. The result is chronic inflammation, a pattern of constant swelling and related biochemical reactions that become highly destructive over time.
“It’s like keeping your car in park but putting your foot on the gas — eventually you’ll overheat,” says Jack Challem, author of The Inflammation Syndrome (John Wiley & Sons, 2003). Left unchecked, chronic inflammation can damage the brain’s memory center and speed up age-related memory loss.
Relax Your Lobes
Chronic stress can take a heavy toll on the brain. That’s because stress hormones, such as corticosteroids, not only contribute to a general environment of inflammation, they also attack the hippocampus — the brain’s memory center — causing atrophy, or shrinkage, in this important area.
Brain imaging studies of people with posttraumatic stress disorder show a significant reduction in the size of the hippocampus. “Stress may shorten the lifespan of brain cells,” says Lippa. “It certainly impacts memory functioning. Over and over again, I see patients’ memories get worse during stressful events.”
Fortunately, how you deal with stress may be more important than the amount of stress you’re shouldering, says Perls. In his studies of centenarians, he found that several of them had aged gracefully despite having had very stressful jobs.
Since some people thrive on stress, Perls thinks the key to staying healthy is not internalizing it. “Stress is most damaging if you let it eat away at you,” he says. “Find a way to do something about it, even if it’s just taking a deep breath.”
If you want to take deep breathing to the next level, you might try meditation. The Eastern approach to relaxation and enlightenment has long been known to alter brain waves, but recent research published in the journal NeuroReport shows it can change the physical structure of the brain as well.
When researchers did a side-by-side comparison of brain scans — half the scans from experienced meditators and the other half from people who’d never tried meditating — they found the meditators’ brains were thicker in areas of the brain charged with interpreting emotions, sights, sounds and touch. The thickest brains belonged to the most experienced meditators, leading the authors to surmise that meditation might strengthen and deepen our neural connections.
The bottom line on brain health? “We have more control than we think,” says Gary Small, MD, director of the Memory and Aging Research Center at the University of California, Los Angeles.
Small estimates that only about one-third of what determines brain health comes from genetics, indicating that factors such as diet, exercise and stress management have a major impact. And, he says, the sooner you get started, the better.
So now you have even more good reason to invest ample time and energy in getting plenty of exercise, eating healthy whole foods and actively managing your stress level. After all, it’s not just your body, but your brain that’s at stake.
And as Small reminds us: “Protecting a healthy brain will always be easier than repairing the brain once it’s damaged.”
Sandra Kettle is a freelance writer in Seattle.