| While there is no fountain of youth for the brain, neuroscience provides evidence for the next best thing. There are lots of things you can do right now to preserve, protect and enhance your gray matter. One hint: If you're already a devotee of a heart-healthy lifestyle, you're way ahead of the game. What's good for the heart is probably good for your head. That's twice the motivation and payoff.
1. Foods for thought—and memory.We are what we eat, the old adage goes. When it comes to brain fitness, eating certain types of food can improve and preserve our sharp-as-a-tack selves. The strategy: Keep unhealthy fats to a minimum (no more than 20 percent of calories). Sticking to a Mediterranean style diet—lots of fresh fruits and vegetables, a minimum of red meat, plenty of fish, daily wine—is paramount. Research shows cellular stress caused by oxidation can lead to cognitive declines. Choose dark-colored fruits and vegetables, including apricots, cantaloupes, watermelon, mangos, kale, chard, spinach and broccoli. Eating these foods increases the production of acetylcholine, a vital chemical released from nerve cells that improves communication between cells. Salmon, mackerel, tuna, sardines and herring also give your brain a boost. What's key about these types of fish is their omega-3 fatty acids, specifically one called DHA, which is an essential component of neural cell membranes that helps to transmit information into and out of those membranes. Brains are made up of about 60 percent fat, but the fuel they rely on is glucose, a simple sugar. To give your brain ample energy, eat complex carbohydrates such as brown rice, bulgur, quinoa, whole-wheat pasta and couscous. Whole grains are superior because they break down more slowly and don't cause big upswings in insulin production, which can cause a number of health problems associated with poor mental performance.
2. Supplemental strategy.Because few among us consume sufficient quantities of healthful foods—how many eat sardines or even salmon three times a week?—most people need dietary supplements to ensure optimum mental function. Make sure your high-potency multivitamin has a sufficient amount of the substances your brain needs most to stay in top shape (or buy additional supplements). Among them:
Folate:A member of the B vitamin group, this nutrient is found naturally in legumes, kidneys, oranges and leafy green vegetables. Few Americans get enough in their diet, so make sure your intake is at least the recommended daily dose of 400 micrograms. One recent study showed that this level of folate provides a 55 percent reduction in the risk of developing Alzheimer's disease. Another study found that people who took 800 micrograms a day did significantly better on memory tests.
Other B vitamins:Vitamins B6 and B12 are believed to be involved in the formation of the sheaths around nerve cells that contribute to communication between these cells. People with Alzheimer's often have reduced levels of B vitamins.
Vitamins C and E together:A Johns Hopkins University study published in 2004 demonstrated that subjects who had the highest levels of these two antioxidants had a greatly reduced chance of contracting Alzheimer's. The most effective doses were 400 to 1,000 International Units of vitamin E, and 500 to 1,500 milligrams of vitamin C.
Omega-3 fats:Eat at least two servings of tuna, salmon or sardines a week, but consider taking a supplement, too. Though there's no recommended amount, most fish oil pills provide plenty. Make sure that a third party has verified the oil is free from contaminants, such as mercury.
3. Drinking and thinking. Sip, don't guzzle, and ask for pinot noir. Alcohol kills brain cells, and the more you drink the more brain cells are destroyed. So it's a no-brainer to keep your consumption in check—no more than a couple of drinks per day for a man or one drink for a woman. In these amounts, alcohol in any form—beer, wine or spirits—is beneficial to the brain. But if you're striving for optimum brain health, red wine should be your drink of choice. That's because it contains an abundance of a potent antioxidant called resveratrol, a type of polyphenol. Resveratrol, also found in berries and peanuts, is a compound produced by plants to ward off disease, in response to such stressors as fungus invasions, injury or infection. Reportedly, the wines with the most resveratrol are those made from pinot noir grapes. White wines, by contrast, contain less than 5 percent of the average amount of resveratrol found in red wines. One recent study presented convincing evidence that resveratrol prevents the buildup of plaques in the brain that snarl intercellular communication. These plaques are a signature of Alzheimer's disease. So in addition to reducing the risk for cancer and heart disease, red wine may also slow (but probably not prevent) the degeneration of neural processes. To your health!
4. Fitting the pill—aspirin and ibuprofen.The daily use of a non-steroidal anti-inflammatory—aspirin and ibuprofen are two of the most common—is considered by some researchers as a promising therapy for keeping the brain healthy in certain groups of older people. But they're not for everyone. Evidence for the brain benefits of aspirin and ibuprofen comes from arthritis studies of people who regularly take significant doses of anti-inflammatory drugs. Researchers found an unanticipated effect: a reduction in the risk of Alzheimer's. One study from the Netherlands, published in 2001, tracked 7,000 people for almost seven years. None had dementia at the start of the study. At the end, those who hadn't regularly taken an anti-inflammatory were six times more likely to be diagnosed with dementia than those who had. Chronic inflammation is known to damage nerve tissues, and examinations of the brains of people with Alzheimer's have shown large areas of inflammation. So there appears to be a correlation between inflammation and dementia, though no one knows if the former causes the latter. While anti-inflammatories may be useful in maintaining brain health, it's too early to recommend their wholesale use. More research needs to be done. Doctors now advise daily aspirin therapy for people at high risk for heart disease, to prevent clotting that could lead to a heart attack or stroke. But serious side affects, such as bleeding ulcers and interference with other medications, can occur. Before starting such a program, you must discuss the pros and cons with your doctor.
5. Minding your meditation. You don't have to join a monastery or hire a guru to reap the substantial rewards of daily meditation. As little as 15 minutes a day may be enough—whether it's sitting in the car waiting to pick up your child from school or in a quiet room at lunchtime. For several years now, western doctors have extolled the virtues of meditation in treating a number of medical conditions, including chronic pain and high blood pressure. The evidence for its effectiveness comes from several studies, including one showing that people with normal to high blood pressure who practiced daily meditation were 23 percent less likely to die—from any cause—than those who didn’t. Amazingly, meditation was more effective at preventing death than other more conventional non-drug therapies, such as exercise, weight loss and salt restriction. Besides counteracting the kinds of cardiovascular ailments that can lead to poor brain function, meditation may also reduce levels of the stress hormone called cortisol. This chemical can wreak havoc with cognitive abilities such as memory recall. But that's not all. A group of U.S. researchers recently found an association between meditation and an increase in the thickness of the cortex, the part of the brain that handles a variety of higher functions. This growth in density suggests that meditation, performed regularly, may put the brakes on the natural thinning of the cortex that takes place as we age.
6. Get on the laugh track. It's long been said that laughter is the best medicine, and science keeps reaffirming the concept. Laughter reduces the stress hormone cortisol in your body; it relaxes your arteries so that cholesterol is less likely to build up; and it even engages you in a bit of exercise (belly laughs activate hundreds of muscles throughout your body). In one study, scientists at the University of Maryland performed an experiment in which subjects watched either a violent war film or a comedy. Before and after the film, the blood flow through the subjects' arteries was carefully measured. Increased flow, called vasodilation, is considered healthful, as it minimizes or prevents blockages that can cause heart attacks or strokes. Those who watched the stress-inducing war film had their blood flow rate drop by an average of 35 percent. But in the comedy-watching group, blood flow increased by 22 percent. This expansion in flow is equivalent to what you'd expect to find in someone who's exercised for about 30 minutes, the researchers reported. Scientists believe laughter may release endorphins, the "feel good" hormones associated with rigorous exercise. These hormones are known to cause blood vessel dilation. So laugh. It's a balm to your brain.
7. Social studies.All primates, including humans, are highly social animals. In a sense, our brains have spent a couple of million years fine-tuning themselves to the nuances of social interactions, because that’s been a lynchpin of survival. But modern society has turned many of us into near-hermits. And that's not only unnatural, it's unhealthy for the brain. For one thing, isolation can cause depression, which the Alzheimer's Foundation of America says leads to higher rates of dementia. Not only do people with wide social networks report a higher quality of life, they also have lower death rates. One large-scale study observed significantly less mental decline in people who had the strongest relationships with others. Relationships stimulate our brains. "There's a lot of evidence that other people are the most unpredictable things you can encounter," says Duke neurobiologist Lawrence Katz. "So activities that have you engaging with other human beings are a fantastic form of brain exercise." There are dozens of ways to engage with folks. Volunteer at a charity or organization. Join a book club, bowling league, or any group dedicated to being actively engaged. And don't forget that pets, especially the highly social dog, can serve some of the same functions as humans in stimulating our minds and relieving stress.
8. You snooze, you win.Although scientists still puzzle over why sleep is necessary, one thing is certain: We cannot survive more than a few weeks without it. When we are denied good, restful, sustained sleep on a regular basis, our brains falter in concentration, learning, memory and alertness. That's no matter how much coffee you might guzzle. The best explanation science has come up with for the healing power of sleep is that brain cells use the "time out" to close down and repair damage. Without sufficient sleep, neurons may not have time to repair all the damage, and so could malfunction during the day. Sleep also may give the brain a chance to perform a workout of sorts among important neuronal connections that might go dormant, explain researchers. Imagine exercising your brain while lying in bed dreaming. What could be better? Most adults require seven to eight hours of sleep each night.
If you have trouble sleeping, here are a few tips:
- Don't eat a heavy meal late in the day.
- Avoid caffeine and alcohol late in the day.
- Get regular exercise, but not close to bedtime.
- If you can't fall asleep or wake up in the middle of the night, get up and read or watch TV until you feel drowsy.
- If you lie awake worrying about things, make a to-do list before going to bed.
9. Jumping jacks for the brain?Well, sort of. By stimulating your mind, you may be able to improve cognitive function, and perhaps delay or even prevent mental disorders such as dementia. Scores of large-scale studies have shown that brain training works. The trouble begins when we fall into routines that seldom challenge our mental faculties. We may be masters at what we do, but we aren't learning new things. And that seems to be key. The mind, according to neuroscientists, is a machine that thrives on learning. "The brain requires active continuous learning," Michael Merzenich, a neurobiologist at University of California, San Francisco, said in an interview with the AARP. "It requires change, and that change requires that you acquire new skills and abilities, new hobbies and activities that require the brain to remodel itself." What kind of activity is best? Scientists aren't sure yet, but agree that anything that expands your knowledge will be effective. The emphasis is on new, as in learning a new language, dance step or sport (the more social the setting the better, as this increases the effect due to the brain benefits of human interaction). Or read a new book or do crossword or sudoku puzzles (which constantly expose you to new information). All these activities build more connections between neural cells, which recent research indicates may even forestall dementia and Alzheimer's.
10. Pump up the hippocampus.How can a rousing, sweat-inducing physical workout benefit your grey matter? By improving blood flow, releasing stress-reducing endorphins, strengthening the connections between brain cells and increasing the number of brain cells themselves. That's just for starters. Regular, cardiovascular exercise—the kind that sends your heart rate up, like walking, bicycling, swimming or even aerobic gardening or house cleaning—is a powerhouse of benefit for both your heart and brain. Studies of fit people show that their attention and concentration are superior to those who don't exercise. And that their gray matter is thicker, suggesting that exercise could protect against the natural decline of mental faculties as we age. One part of the brain that's known to be directly influenced by exercise is called the hippocampus. It's sort of a "clearing house" for the brain, deciding which information sent to it by the senses gets stored away into memory, and then retrieving it when necessary. It's vital for learning and making associations. Research has shown that physical exercise stimulates the production of new brain cells, called neurons, in the hippocampus. Exercise is almost too good to be true as a tonic for the brain. As neurobiologist Carl Cotman told the AARP: "It's sort of surprising to think about. You're literally building the structure of the brain, just by moving your feet."
11. Learn the word "neurobics." A melding of the words "neuron" (brain cell) and "aerobics," neurobics is the brainchild of the Duke University neurobiologist Lawrence Katz and author Manning Rubin. In the book Keep Your Brain Alive (Workman Publishing, 1998), they outline an unusual brain exercise program that's based on a solid foundation of neuroscience research. Specific kinds of sensory stimulation, they believe, causes brain cells to secrete molecules called neurotrophins that act like nutrients to improve cellular health. What's the best sort of stimulation? Katz and Rubin offer 83 activities that make you "experience the unexpected and enlist the aid of all your senses." Try showering with your eyes closed, tuning in to the sounds and feel of water on your skin. Use your non-dominant hand to brush your teeth or comb your hair. Wear earplugs at the dinner table. Take one of your children to work with you. Learn to read Braille. What's important is that the activity be completely removed from your regular routine. And the more senses you engage, the better. If you normally go to work using the same route, try a different one. At a stop light, roll down the window and close your eyes, listening to the sounds, feeling the air on your face. Your brain is forced to work with a new set of sensory inputs, which builds connections in your neuronal network. Humans are hardwired to seek novelty, yet in our tame modern environment, that’s more difficult to do. By consciously exposing your brain to novel situations, it responds like a long underused muscle to a weight training program: It grows!
Scott McCredie is a Seattle-based health writer and author of the book Balance: In Search of a Lost Sense.
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