There's good evidence that what you eat can make a difference in your risk of cognitive decline and dementia, including Alzheimer's disease. Here's what to do about it.

By Mayo Clinic Staff

The research is in: Eating certain foods (and avoiding others) has been shown to slow brain aging by 7.5 years, and lessen the chances of developing Alzheimer's disease.

This isn't some trendy diet of the moment. Born as a hybrid of two existing eating styles with decades of research at their backs — the DASH diet and Mediterranean diet — university researchers developed the MIND diet to emphasize foods that impact brain health.

Here's what that looks like:

Just like Mom always told you: Eat your vegetables. But unique to the MIND diet, researchers found that green leafy ones like kale, collards, spinach or lettuce were specifically shown to lower the risk of dementia and cognitive decline.

Greens are packed with nutrients linked to better brain health like folate, vitamin E, carotenoids and flavonoids. And one serving a day has been shown to slow brain aging.

To max out your veggie score, aim to eat at least six servings a week of greens. Then round it out with at least one serving of other vegetables a day.

Nothing against the apple a day, but when scientists reviewed the research on diet and brain health, one type of fruit soared above the rest: berries.

In a 20-year study of over 16,000 older adults, those who ate the most blueberries and strawberries had the slowest rates of cognitive decline. Researchers credit the high levels of flavonoids in berries with the benefit.

Treat yourself to two or more berry servings a week for peak brain health.

Nuts may be high in calories and fat, but they're packed with fat-soluble vitamin E, known for its brain-protective qualities.

Grab a handful at least five times a week instead of processed snacks like chips or pastries. Check the list of ingredients and opt for the dry-roasted or raw, unsalted kind without extra sodium, sweeteners or oils. (Hint: No-stir peanut butters have stuff added.)

Another Mediterranean diet staple that has a home in the MIND diet is olive oil. Researchers recommend using it as your primary cooking oil, and avoiding butter and margarine.

New to olive oil? Look for "extra virgin" olive oil (skip anything labeled "light") and choose a bottle that's opaque or dark glass since light causes it to go bad faster.

Brain-healthy eating encourages consuming meat sparingly (red meat makes an appearance fewer than four times a week in the ideal MIND diet). Beans, lentils and soybeans, which pack protein and fiber, make a worthy substitute. They'll keep you full and are rich in B vitamins, which are important for brain health.

In one study analyzing the diets of older adults, those who had the lowest intakes of legumes had greater cognitive decline than those who ate more.

Constantly forgetting the name of that person you just met? Adults age 65 and older who ate fish once a week or more scored better on memory tests and tricky number games than those who had seafood less often.

But if fish isn't your favorite, there's good news: MIND diet researchers couldn't find proof that having it more than once a week added extra benefits for the brain.

While too much alcohol is unquestionably harmful to the brain and overall health, studies suggest that light to moderate drinking may lower the risk of dementia. And it may delay the onset of Alzheimer's by two to three years.

One possible reason: Alcohol seems to help blood flow, making it less sticky and less prone to potentially harmful clotting.

Given the risks of alcohol, it's probably not a good idea to start drinking it just for the possible brain benefit. But if you enjoy a glass of wine with dinner, you can continue the habit on the MIND diet.

July 31, 2019