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Shake It Up
Chow down at the same restaurant every date night? Jog the same route? Mixing it up could keep you younger—and sharper. "New surroundings and experiences can stimulate new ways of thinking, which keeps your brain young and vibrant," says Marie Pasinski, M.D., staff neurologist at Massachusetts General Hospital and author of Beautiful Brain, Beautiful You.
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The next time you're bored by the pool, break out a board game or deck of cards. Exercising your mind with a game that requires brainpower, like chess or bridge, is more than just fun, says Louis Matzel, Ph.D., professor of behavioral science at Rutgers University. "These types of games are inherently challenging, while at the same time they tax your working memory," he says.
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Whip Up Some Guac
The perfect summer dip is more than just a yummy accompaniment for your favorite chips. Guacamole is a great source of vitamin E, which research by Martha Clare Morris, Sc.D., director of the section on nutrition and nutritional epidemiology in the department of internal medicine at Rush University in Chicago, says may ward off Alzheimer's disease.
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Get Out of Town
Traveling, especially abroad where English isn't spoken, can make you smarter. "There is a great deal of recent research demonstrating that bilingualism enhances cognitive function," says Judith Kroll, Ph.D., professor of psychology, linguistics, and women's studies, and director, center for language science at Pennsylvania State University.
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Not only are they the perfect snack for a summer road trip (hello, feel-full protein!), nuts also keep your mind sharp. Almonds and cashews are rich in magnesium (a handful gives you 20 percent of your daily requirement), which was found to improve learning and memory in mice, according to research published in the journal Neuron. In another study at New York State Institute for Basic Research in Developmental Disabilities, mice that ate the equivalent of one ounce of walnuts showed improvement in learning, memory, emotional regulation and motor coordination compared with those who went nut-free.
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Visit the Farmers' Market
Summertime equals fantastically fresh fruits and veggies in innumerable hues. "Research shows that people who consume a diet rich in fruits and vegetables are not only leaner but have sharper memories," Dr. Pasinski says. Choose produce in a variety of colors to get lots of phytonutrients, which are great for the body and brain, she says.
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Write Down Memory Lane
If you're feeling forgetful, follow the lead of Leisha Holland of Powder Springs, Georgia. "My old friends from summer camp and I have started writing letters in the summer. It keeps my memories fresh, and it's a great way to catch up," she says. "We share the latest news in our lives, plan vacations, and share our thoughts about the latest Hollywood gossip. It's not much, but it's exciting, and I feel like it makes my mind a little sharper."
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Embrace Your Inner Red Rover
The next time the kids are playing Mother May I? or Capture the Flag in the front yard, join in. "Playing like a kid brings the brain into focus and keeps you energized," says John Ratey, Ph.D., associate clinical professor of psychiatry at Harvard Medical School, and author of Spark: The Revolutionary New Science of Exercise and the Brain. "Playful exercise can regulate your mood, increase attention span and lower stress."
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Atlantic salmon, Pacific cod and tuna are some of the best food sources of docosahexaenoic acid (DHA for short), the omega-3 fatty acid that's been shown to improve memory and learning. So grill it, bake it or steam it, but don't fry it. Fatty, fried foods have been linked to a decline in cognitive function.
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Be a Nature Girl
The summer months practically beg for shady walks in the woods, chill-time by the lake, and any other activity that puts you out of doors. According to a University of Pittsburgh study, spending just one hour in nature—sorry, city slickers—can boost memory and attention by 20 percent. And a walk in nature is a double bonus. Walking six to nine miles per week appears to protect the brain against shrinkage, according to the study.
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Don't Skip the Neighborhood Barbecue
What's summer without some grilling and friendly chitchat with the neighbors? It turns out this rite of the season is actually good for your mind. A University of Michigan study found that people who engaged in social interaction displayed higher levels of cognitive performance than those who didn't. But keep it friendly. A follow-up study by the same researchers found that friendly chats boosted brainpower, while convos that were competitive in nature didn't.
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If you can't remember where you left the sunscreen, your waterproof camera, or your sunglasses (psst—try on top of your head!), you may be a candidate for the ancient yogic technique of left-nostril breathing. A study published in the Indian Journal of Physiology and Pharmacology found that holding the right nostril closed and breathing only through the left improves spatial memory, the kind that helps you remember where you put things.
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"Leafy vegetables—think spinach, watercress and kale—are like the fountain of youth for your body and mind," Dr. Pasinski says. In fact, a Harvard Medical School study of more than 13,000 women found that those who frequently ate green leafy vegetables took one to two years off their mental age compared with those who ditched greens.
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Schedule Tea Time
Just because it's a scorcher out there doesn't mean you have to send your tea leaves packing. Brew a pot, pour it over ice, then sit back and get smart. According to a study at UCLA, regular tea drinkers slowed cognitive decline by up to 37 percent.
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Beef Up on Books
... or at least the bestseller list. "I love to start my weekend mornings with a cup of coffee and the New York Times Book Review," says Courtney Lucas of Birmingham, Alabama. "The coffee perks up my mind, and the reviews guide me to the next bestseller to dive into. It makes for great conversation at cocktail parties too. Who doesn't want a recommendation for the beach?"
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Sometimes it's easy to agree with the old adage "You can't teach a dog new tricks," but actually believing might make it true. According to Stanford University studies, subjects who believed they were capable of learning more were more motivated to learn and thus increasing their mental abilities. Those who thought they were trapped in their IQ encountered the opposite experience.
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Snack on Celery
It's not just for the kiddos' lunch boxes (ants on a log, anyone?). Celery is rich in luteolin, a compound that has been found to reduce brain inflammation and reverse age-related memory loss in mice, according to a study at the University of Illinois. Other luteolin-rich eats are carrots, peppers and olive oil.
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Yet another reason to fit in that sweat session: "Studies show that aerobic exercise actually increases the size of the brain, making it stronger and healthier," Dr. Pasinski says. "Aerobic exercise enhances concentration, learning and memory. It also uplifts our mood, relieves anxiety and has been shown to stave off dementia as we age." Take a splash in the pool, a stroll on the beach, or a bike ride through your neighborhood to up your smarts and whittle your waist.
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Play with Words
"For my family, summer means lots of Scrabble games," says Susan Wayland of White Stone, Virginia. "It's a family tradition, and we all like to think that unscrambling those seven letters into words is making us smarter as we go. My mother, who passed away at the age of 93 still sharp as a tack, attributed her thriving brainpower to playing Scrabble every day and having a gin martini every night." Wayland may be on to something. According to a study published in the journal Neurology, exercising word skills may protect against memory loss.
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Get Your Zzz's
With summer's longer days, getting enough sleep can be tricky, but it's crucial for a strong mind. "Studies show that we store memories and actually learn while we sleep," Dr. Pasinski says. In other words, the better you sleep, the more information your brain will retain. Hello, naptime! A nap can help cognitive function too.