A study conducted by researchers at Columbia University Mailman School of Public Health and The Robert Butler Columbia Aging Center found that a healthier diet is linked to a reduced risk of dementia and a slower aging process. This study provides valuable insights into the biological mechanisms underlying this association. The findings were published in the Annals of Neurology.

“Much attention to nutrition in dementia research focuses on the way specific nutrients affect the brain,” said Daniel Belsky, PhD, associate professor of Epidemiology at Columbia School of Public Health and the Columbia Aging Center, and a senior author of the study. “We tested the hypothesis that a healthy diet protects against dementia by slowing down the body’s overall pace of biological aging.”

A healthy diet can have a positive impact on aging and reduce the risk of dementia in several ways:

  • Nutrient-rich foods: Consuming a variety of fruits, vegetables, whole grains, and lean proteins provides essential vitamins, minerals, and antioxidants that support brain health and help combat oxidative stress, a factor associated with aging and cognitive decline.

  • Omega-3 fatty acids: Foods like fatty fish (salmon, mackerel), walnuts, and flaxseeds that are rich in omega-3 fatty acids have been linked to a reduced risk of dementia. These healthy fats support brain function and help reduce inflammation.

  • Antioxidants: Foods rich in antioxidants, such as berries, dark chocolate, and green leafy vegetables, can help protect brain cells from damage caused by free radicals, potentially reducing the risk of age-related cognitive decline.

  • Healthy blood sugar levels: A diet that includes whole grains, legumes, and low-glycemic index foods can help regulate blood sugar levels. High blood sugar levels over time can contribute to cognitive decline and increase the risk of dementia.

  • Overall heart health: A healthy diet that supports heart health, such as the Mediterranean or DASH diet, can also benefit brain health. What is good for the heart is often good for the brain, as it promotes good blood flow and reduces the risk of conditions like hypertension and stroke, which are linked to cognitive decline.

Remember, a healthy diet is just one aspect of a holistic approach to aging well and reducing dementia risk. Regular physical activity, mental stimulation, quality sleep, and social engagement are also important factors to consider.

A nutritious diet can help slow down the aging process and lower the chances of developing dementia. By consuming a variety of fruits, vegetables, whole grains, lean proteins, and healthy fats, you can provide your body with essential nutrients that support brain health and overall well-being.

Healthy diet can protect against dementia

The study conducted by researchers at Columbia University Mailman School of Public Health and The Robert Butler Columbia Aging Center found that a healthier diet is linked to a reduced risk of dementia and a slower aging process. This study provides valuable insights into the biological mechanisms underlying this association. The findings were published in the Annals of Neurology.

“Testing the hypothesis that multi-system biological aging is a mechanism of underlying diet-dementia associations was the logical next step,” explained Belsky. The research determined that higher adherence to the Mediterranean-Dash Intervention for Neurodegenerative Delay diet (MIND) slowed the pace of aging as measured by DunedinPACE and reduced risks for dementia and mortality. Furthermore, slower DunedinPACE accounted for 27 percent of the diet-dementia association and 57 percent of the diet-mortality association.

“Our findings suggest that a slowed pace of aging mediates part of the relationship of a healthy diet with reduced dementia risk, and therefore, monitoring the pace of aging may inform dementia prevention,” said first author Aline Thomas, PhD, a postdoc at the Columbia Department of Neurology and Taub Institute for Research on Alzheimer's Disease and the Aging Brain(link is external and opens in a new window). “However, a portion of the diet-dementia association remains unexplained, therefore we believe that continued investigation of brain-specific mechanisms in well-designed mediation studies is warranted.”

Brain-boosting foods that can fight dementia

Colorful Fruits and Vegetables

Studies have found that foods with higher levels of carotenoids–the pigments that give fruits and veggies their orange and red color–are associated with better brain health and a lower risk of dementia. Foods that are rich in carotenoids include carrots, squash, sweet potatoes, bell peppers, tomatoes, papaya, apricots, and leafy greens such as spinach and kale.

Berries

Berries are a great source of antioxidants and flavonoids, both of which are known to prevent cell damage and can stop the progression of brain damage from free radicals. Foods such as blueberries, blackberries and raspberries all pack this nutritional punch–plus they have the added benefit of being naturally lower in sugar than many other fruits.

Fish

Seafood, in particular fatty fish such as tuna and salmon, is an excellent source of omega-3 fatty acids, which are associated with good brain health and a reduced risk of cognitive decline. The omega-3 fatty acid docosahexaenoic acid (DHA) is especially helpful in this regard, but our bodies cannot produce it on their own so we have to rely on diet. Experts say two to three servings of fish a week is enough to provide your brain with all the benefits of this nutrient.

Nuts, seeds and legumes

Nuts, seeds and legumes contain antioxidants and omega-3 fatty acids, as well as other nutrients such as vitamin E, B vitamins, choline, magnesium and zinc. All of these are shown to promote brain health and reduce age-related cognitive decline. Foods such as walnuts, almonds, peanuts, soybeans, lentils, flax seeds and pumpkin seeds are all good choices to add to your diet if you’re looking to score these benefits.

Whole grains

Whole grains are rich in fiber, B vitamins and other nutrients and can reduce inflammation in the brain, supporting memory and warding off dementia. Whole grains such as quinoa, barley, brown rice and oats are great choices and can be healthier alternatives to more processed grains, such as white flour.

10 foods to eat regularly to boost your brain

  • Wholegrains (three or more servings a day)

  • Green leafy vegetables, such as spinach, cabbage, spring greens, kale and salad leaves (one or more servings a day)

  • Other vegetables (one or more servings a day)

  • Nuts (on most days)

  • Beans and lentils (three or more servings a week)

  • Berries, including blueberries and strawberries (two or more servings a week)

  • Chicken or turkey (two or more servings a week)

  • Fish (one or more servings a week)

  • Olive oil (as the main oil or fat you use)

  • Wine (no more than one small glass a day–more than this and it becomes more likely to harm health than help it).

Five foods to avoid or limit to help your brain

  • Fried or fast food (less than once a week)

  • Cheese (less than once a week)

  • Red meats (less than four times a week)

  • Pastries and sweets (less than five times a week)

  • Butter (less than one tablespoon a day).

The diet is relatively new. The first study of its effectiveness, which followed people for an average of 4.7 years, was published in 2015, so it’s early days. That study, which included 960 people, suggested that those who stuck most closely to the diet had brains that were the equivalent of 7.5 years younger than those who followed the diet the least. The diet also appears to reduce your risk of dementia even if you can’t stick to every recommendation 100 percent of the time. But there’s not enough research for it to be part of national dietary guidelines. We need further studies to confirm the findings and refine the specific foods and quantities included. We know this type of diet can help protect heart health. Heart disease and dementia share many risk factors (including high cholesterol and obesity), so it makes sense that a heart-healthy diet could also reduce your risk of dementia.

In one randomized controlled trial performed in Israel and published this year, for instance, researchers took brain scans of more than 200 people who had been split into three diet groups. They found that after 18 months, those who followed a “green” Mediterranean diet—one rich in Mankai (a nutrient-packed green plant), green tea and walnuts—had the slowest rate of age-related brain atrophy. Those who followed a traditional Mediterranean diet were close behind. Those who followed regular healthy diet guidelines—which was less plant-based and allowed for more processed and red meat than the other two diets—had greater declines in brain volume.

Researchers looked at nearly 1,000 people ages 60 to 100 living in Chicago retirement communities or senior public housing who did not have dementia, and followed them for about seven years, on average. Each year, participants filled out diet questionnaires and completed cognitive and memory tests. The researchers found that those who consumed the most flavonoids had slower rates of cognitive decline than people who ate the least. “Those that consumed the highest level of flavonols—an average of seven servings of dark leafy greens per week—versus the lowest, had a 32 percent decrease in their rate of cognitive decline,” said Dr. Thomas M. Holland, who led the study and researches the chronic diseases of aging at the Rush Institute for Healthy Aging in Chicago.

(Article written by Dr. Thiago Freire and Tukakula Swetha Reddy)