Eating a Mediterranean diet -- rich in produce, olive oil and fish -- improves brain functioning and lowers the risk of Alzheimer's disease, according to a new review of the available research.

The review, published in the journal Epidemiology, includes 12 studies, nine of which showed an association between eating a Mediterranean diet and having lower Alzheimer's risk, improved cognitive functioning and lower rate of cognitive decline.

However, the researchers did not find definitive associations between eating a Mediterranean diet and having decreased risk of mild cognitive impairment (considered to be more severe cognitive decline than that which comes from aging, but not yet full-blown dementia).

"Mediterranean food is both delicious and nutritious, and our systematic review shows it may help to protect the aging brain by reducing the risk of dementia. While the link between adherence to a Mediterranean diet and dementia risk is not new, ours is the first study to systematically analyze all existing evidence," study researcher Iliana Lourida, of the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care in the South West Peninsula, said in a statement.

Recent research has also tied eating a Mediterranean-style diet with a lower risk of diabetes, living a longer lifespan and having a lower risk of heart disease.

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  • Flaxseed Or Flaxseed Oil

    Flaxseed is one of the most highly-recommended plant sources for omega-3s. Ground flaxseed is a staple in my kitchen -- it keeps for a long time in the freezer, and because flaxseed is virtually tasteless, I throw it in all sorts of things -- cereal, oatmeal, smoothies -- to boost my omega-3 intake. You can use ground flaxseed goo as an egg substitute in vegan baking. Flaxseed oil has <a href="http://www.krispin.com/omega3.html#Supplementing" target="_hplink">7980 mg omega-3's per 1-tbsp serving</a>. <strong>More from Blisstree.com:</strong> <a href="http://blisstree.com/move/best-fitness-trackers-similar-to-the-nike-fuel-band-658/" target="_hplink">The Best Fitness Trackers</a> <a href="http://blisstree.com/eat/supplements/which-is-better-krill-oil-or-fish-oil-841/" target="_hplink">Krill Oil vs. Fish Oil</a> <a href="http://blisstree.com/feel/eat-for-your-teeth-omega-3s-could-prevent-gum-disease/" target="_hplink">Eat for Your Teeth: Omega 3s Could Prevent Gum Disease</a> <em>Flickr photo by <a href="http://www.flickr.com/photos/alishav/3462217890/" target="_hplink">Alisha Vargas</a></em>

  • Chia Seeds

    Chia seeds are another plant source of omega-3's that I like to sneak into my diet. You can throw chia seeds into stir fry, salads, seitan, dips and more. Like ground flaxseed, chia seeds have a mild -- if any -- taste. But they'll add a dose of omega-3's and a slight crunch wherever they're added. <em>Flickr photo by <a href="http://www.flickr.com/photos/notahipster/4998594527/" target="_hplink">little blue hen</a></em>

  • Hemp Seeds

    Vegan and gluten-free, hemp seeds also have the most essential fatty acids of any nuts or seeds and a perfect 3:1 <a href="http://today.msnbc.msn.com/id/16637630/ns/today-food/t/nutty-hemp-hot-food-trend/" target="_hplink">ratio of omega-3 to omega-6</a>. They're also high in protein, minerals and rare polyunsaturated fatty acids like gamma-linolenic acid (GLA) and stearidonic acid (SDA). Like flax and chia seeds, you can sprinkle hemp seeds into lots of different things. Store in the freezer to keep them from going bad. <em>Flickr photo by <a href="http://www.flickr.com/photos/restlessglobetrotter/3425782783/" target="_hplink">Jason Rogers</a></em>

  • Perilla Oil

    Perilla oil comes from the seeds of the herb perilla. Over 50 percent of perilla oil consists of ALA, with about <a href="http://www.krispin.com/omega3.html#Supplementing" target="_hplink">8960 mg omega-3 fatty acids</a> per tablespoon (compared to 1680 mg omega-6's).

  • Cauliflower

    "Many people are not aware that cauliflower contains a good amount of omega-3 essential fatty acids, making this veggie great for heart health," says nutritionist Margaux Rathbun. "In addition to the omega-3, cauliflower contains other heart-friendly nutrients including potassium, magnesium and niacin." <a href="http://nutritiondata.self.com/facts/vegetables-and-vegetable-products/2390/2" target="_hplink">One cup contains about 37 mg of omega-3's</a>. To retain the nutrients in cauliflower, Rathbun recommends steaming it for no more than five to six minutes, then adding lemon juice and cold-pressed extra-virgin olive oil. <em>Flickr photo by <a href="http://www.flickr.com/photos/wordridden/4626951567/" target="_hplink">Jessica Spengler</a></em>

  • Hummus

    "Hummus is a vegan source of omega-3's," with about 300 mg in a one-cup serving, explains Charis Freiman-Mendel, author of "Cook Your Way Through the S.A.T.". That's because hummus is made with tahini, which is made from omega-3-packed sesame seeds. "Delicious, healthy, great brain food," says Freiman-Mendel. <em>Flickr photo by <a href="http://www.flickr.com/photos/alga/3122887625/" target="_hplink">Albertas Agejevas</a></em>

  • Purslane

    Purslane is a salad or cooking green with a slightly peppery taste. It's got <a href="http://www.health.com/health/gallery/0,,20487719_5,00.html" target="_hplink">400 mg of omega-3's per serving</a>. It's also high in <a href="http://nutritiondata.self.com/facts/vegetables-and-vegetable-products/2604/2" target="_hplink">vitamin A</a>, calcium, potassium and iron.

  • Brussels Sprouts

    One serving of Brussels sprouts contains about 430 milligrams of alpha-linolenic acid -- more than one-third of the <a href="http://www.nal.usda.gov/fnic/DRI//DRI_Energy/energy_full_report.pdf" target="_hplink">daily ALA amount recommended</a> by the National Academy of Sciences. "These tasty little green veggies are loaded with nutrients, including omega-3 fatty acids," says nutritionist Margaux Rathbun. "They're the perfect food for promoting healthy and beautiful skin. Try steaming them for about five minutes to keep all of the health-promoting nutrients intact." <strong>More from Blisstree.com:</strong> <a href="http://blisstree.com/move/best-fitness-trackers-similar-to-the-nike-fuel-band-658/" target="_hplink">The Best Fitness Trackers</a> <a href="http://blisstree.com/eat/supplements/which-is-better-krill-oil-or-fish-oil-841/" target="_hplink">Krill Oil vs. Fish Oil</a> <a href="http://blisstree.com/feel/eat-for-your-teeth-omega-3s-could-prevent-gum-disease/" target="_hplink">Eat for Your Teeth: Omega 3s Could Prevent Gum Disease</a> <em>Flickr photo by <a href="http://www.flickr.com/photos/39975765@N05/6399983389/" target="_hplink">Mallory Dash</a></em>

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