You are what you eat — or at least, your brain is.

Medical researchers are discovering how everyday foods can contribute to the risk of declining brain health and dementia.

At the same time, however, they’re also finding that some foods and beverages can help you maintain healthy cognitive functioning well into old age.

“There may be some potent nutritional tools in your home to help fight the inflammation that could contribute to brain aging,” Dr. Nikolaos Scarmeas, a Fellow of the American Academy of Neurology, said in a news release.

“Diet is a lifestyle factor you can modify, and it might play a role in combating inflammation, one of the biological pathways contributing to risk for dementia and cognitive impairment later in life,” Scarmeas added.

Eat these foods to prevent dementia

In a groundbreaking 2021 study, published in the journal Neurology, Scarmeas and a research team from the National and Kapodistrian University of Athens looked at 1,059 people in Greece with an average age of 73 who did not have dementia.

The study participants were surveyed about their diets and were ranked on how anti-inflammatory their eating and drinking habits were.

People with dementia ate fewer whole foods

After three years, 62 of the people developed dementia — and those who developed the disease consumed about half as much of the following four items as those who did not show symptoms of cognitive decline:

• Beans and other legumes
• Tea and coffee
• Fruits
• Vegetables

“Our results are getting us closer to characterizing and measuring the inflammatory potential of people’s diets,” Scarmeas said. “That in turn could help inform more tailored and precise dietary recommendations and other strategies to maintain cognitive health.”

Find the flavanols

Other studies have found similar results. A recent report from the Proceedings of the National Academy of Sciences revealed that people whose diets were low in flavanols — a substance found in certain foods — had better memories after three years of taking flavanol supplements.

Flavanol-rich foods include:

• Red wine
• Black and green tea
• Dark chocolate
• Beans
• Kale
• Watercress
• Onions
• Cherries
• Blackberries
• Black grapes
• Apples

Foods to avoid that lead to dementia

Meanwhile, a large and growing body of evidence finds that many foods — especially highly processed and fast foods — can contribute to dementia.

A study published last year in Neurology as well found that for every 10% increase in daily intake of highly processed foods, the risk of dementia increased by 25%.

Participants in the study included over 72,000 men and women living in the UK who were 55 or older and had no symptoms of Alzheimer’s disease or other forms of dementia.

The researchers tracked them for an average of 10 years, during which time 518 were diagnosed with dementia or Alzheimer’s disease. Those who ate the most highly processed foods were at highest risk of developing dementia.

Examples of highly processed foods:

• Fast foods
• Soft drinks, including diet
• Un-fresh fruit juices
• Pre-packaged snacks
• Bottled sauces and dressings
• Store-bought breads
• Frozen dishes
• Deli meats

Meanwhile, those who ate the fewest highly processed foods — less than 10% of their daily food intake — had the lowest risk of dementia.

“Ultra-processed foods are meant to be convenient and tasty, but they diminish the quality of a person’s diet,” study author Huiping Li, of Tianjin Medical University in China, said in a news release.

“These foods may also contain food additives or molecules from packaging or produced during heating, all of which have been shown in other studies to have negative effects on thinking and memory skills,” Li added.

Highly processed foods contain:

• Added sugars
• Refined carbohydrates
• Salt
• Saturated fats
• Artificial flavors and dyes
• Unnatural preservatives, e.g. sodium benzoate, sorbic acid, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT)

Apparently, eating an apple a day to keep the doctor away isn’t just an old children’s rhyme.

“Our results also show increasing unprocessed or minimally processed foods by only 50 grams a day, which is equivalent to half an apple … and simultaneously decreasing ultra-processed foods by 50 grams a day … is associated with 3% decreased risk of dementia.”