Your Brain on Food: How What You Eat Affects Cognition

An anti-inflammatory, plant-forward approach to eating may be a path to better cognitive function and a lower risk of dementia.

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What you eat may impact your brain health today and for years to come. Recent research into the effects of food choices on dementia outcomes suggests that following an anti-inflammatory, plant-forward diet is associated with better cognitive function and a lower risk of neurological disorders such as Alzheimer’s.

The World Health Organization estimates that more than 55 million people have dementia worldwide, and cases are expected to surpass 150 million by 2050. Yet it’s possible that as many as 45 percent of these cases could be prevented by controlling “modifiable risk factors,” including conditions associated with inflammation, such as high blood pressure, high cholesterol, diabetes, and obesity.

By making dietary changes that emphasize foods associated with improved cognition, it may be possible to reduce your risk of dementia—or improve overall brain function.

The Inflammation Connection

Chronic inflammation appears to play a key role in pathways related to the development of dementia. In their book “The Alzheimer’s Solution,” Drs. Dean and Ayesha Sherzai detail several factors that can contribute to or arise from an inflammatory state:

• Oxidative stress, a process in which unstable molecules called free radicals cause damage to other cells and trigger your body’s inflammatory response
• Insulin resistance, which can cause high blood sugar and potentially promote oxidative stress
• Lipid dysregulation, a condition in which fats build up in the bloodstream, where they can oxidize and become pro-inflammatory

According to the Sherzais, these combined factors may lead to dementia by damaging brain cells and blood vessels. This damage impairs the brain’s ability to clear cellular waste and promotes the formation of plaques and amyloid proteins that can block blood flow and interfere with brain cell function.

The Brain Science of Food

Food may be particularly influential in brain inflammation.

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“The brain is an energy-intensive organ, consuming around 20 [percent] of the body’s energy,” Megan Lee, assistant professor at Bond University and founder of Food Mood Doctor, told The Epoch Times in an email. “Nutrients from food provide fuel, repair mechanisms, and signaling pathways necessary for healthy brain function.” Lee is also secretary of the International Society of Nutritional Psychiatry Research.

That means that a significant amount of what you eat goes toward powering your brain and supporting—or inhibiting—activities such as cognition.

Diet appears to begin influencing brain health early in life. A 2023 study in the European Journal of Epidemiology assessed the diets, brain development, and IQs of thousands of children and found a significant association between eating patterns and cognitive development.

Mothers filled out four-week diet questionnaires for their children at age 1 and again at age 8. From these, researchers identified dietary patterns based on intakes of foods such as fruits, vegetables, grains, fats, and snacks. Two dietary patterns had measurable effects on the children’s brain development: snacks, processed foods, sugar, whole grains, soft fats, and dairy.

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A soft fat refers to a fat that’s typically liquid at room temperature.

MRIs of the children’s brains at age 10 showed that those who followed a low-quality, Western-style diet high in snack foods, processed foods, and sugars from infancy had lower total cerebral matter. By contrast, children whose diets incorporated whole grains, soft fats, and dairy products early in childhood had more cerebral gray matter and greater gyrification—folds in the cortex that create more total brain surface area.

Researchers noticed increased gyrification in areas important for functions such as literacy, math, reasoning, memory, and decision-making. These changes appeared to influence IQ scores, which were assessed at age 13.

Other studies have sought to identify specific foods and dietary patterns that may support cognitive health. One such diet, the Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay diet, known as the MIND diet, combines the approaches of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets, both known for their anti-inflammatory properties.

MINDing Your Nutrition

The Mediterranean diet is patterned after eating habits common to European countries bordering the Mediterranean Sea. It is noted for its focus on whole, minimally processed plant-based foods, lean proteins, and unsaturated fats.

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The DASH diet was designed to help control factors that may contribute to high blood pressure, which affects nearly half of adults in the United States. It takes a similar approach to the Mediterranean diet by reducing the intake of salt, added sugar, and high-fat meat and dairy products.

The MIND diet emphasizes leafy greens and other vegetables, encourages frequent consumption of whole grains, nuts, beans, and berries, and recommends olive oil as the only added fat. Minimal amounts of poultry and fish may be included, and foods high in saturated and trans fats should be avoided. The overall dietary pattern is high in compounds and nutrients such as fiber, polyphenols, carotenoids, omega-3 fats, and vitamins C and E, which may contribute to the beneficial effects observed in research.

In a 2023 prospective study and meta-analysis published in The American Journal of Clinical Nutrition, researchers conducted a study that included 4,066 Chinese adults over age 55 and reviewed existing research to evaluate the effects of the MIND diet on cognitive health. Their results showed that closer adherence to the diet correlated with better cognitive function and “potentially slower cognitive decline in later life.”

Additional research suggests that the Mediterranean and DASH diets may lower pro-inflammatory markers, prevent cognitive decline, and support cognitive performance.

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A 2023 meta-analysis in the Journal of Neurology showed that a high intake of ultra-processed foods is associated with an increased risk of all types of dementia, including Alzheimer’s disease.

The Ultra-Processed Brain

“Numerous studies have shown that ... poor dietary habits like increased consumption of ultra-processed, and refined and sugary foods are linked to cognitive decline, increased risk of dementia, and mental health issues,” Lee told The Epoch Times.

Ultra-processed and refined foods tend to be high in saturated fat, trans fat, and refined carbohydrates and low in fiber, a combination that appears to increase the cardiometabolic risk factors that may influence the development of dementia. Processed red meats, which are often high in salt and contain additives such as nitrates, are also associated with a greater risk of all-cause dementia.

Lee said eating these foods “can lead to oxidative stress, inflammation, and insulin resistance, all of which can impair brain function.”

Ultra-processed fare may also alter the gut microbiome and promote inflammation that can damage the gut’s protective lining.

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Several types of beneficial gut bacteria feed on fiber and produce compounds called short-chain fatty acids, which have been shown to reduce inflammation and strengthen the gut barrier.

Ongoing research shows a potential connection between disruptions in gut health and the development and progression of cognitive disorders such as Alzheimer’s. When the gut barrier is damaged, pro-inflammatory compounds and bacterial toxins can pass through junctions between cells, enter the bloodstream, and potentially travel to the brain, where they can damage the blood-brain barrier and promote brain inflammation and neurodegeneration.

A Flexible Approach

There may not be a one-size-fits-all eating plan for better cognition. Laura M. Ali, a registered dietitian, culinary nutritionist, and author of “MIND Diet for Two,” told The Epoch Times that nutrition is a very young science. “We’re still learning about it,” she said.

Rather than a strict set of rules, evidence suggests that focusing on whole and minimally processed plant foods and minimizing ultra-processed foods and processed red meats may be the best approach to prevent cognitive decline.

Lee said emphasizing a range of plant foods such as legumes, whole grains, nuts, seeds, and fresh fruits and vegetables is particularly protective.

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“Plants are full of antioxidants, polyphenols, and dietary fibre that support mood and mental health,” Lee wrote.

She also recommended avoiding pro-inflammatory foods such as processed meat, refined carbohydrates, and packaged snacks that contain trans fats.

If you include animal foods in your diet, Ali recommended choosing choline-rich eggs. Choline is a precursor to the neurotransmitter acetylcholine, which helps with functions such as memory, learning, attention, and arousal. According to Ali, research shows that people with higher choline levels show better performance on memory and learning tests.

Although excess meat consumption has been implicated as a factor in the risk of cognitive impairment, some research suggests that unprocessed red meats may have a beneficial effect.

In one population-based study, researchers observed an increase in the risk of all-cause dementia and Alzheimer’s for every additional 25 grams of processed meat eaten per day. However, each 50 gram increase in unprocessed red meat was associated with lower risks, suggesting that unprocessed red meat may have a place in a brain-healthy diet.

The Best Diet for Cognitive Health

Ali said the research is encouraging for people who see dietary change as an all-or-nothing prospect. Following a framework such as the MIND diet, she said, simply shifts the emphasis from meat-focused with a little bit of plants to plant-focused with the option for some meat, fish, and eggs.

“So the broad dietary pattern is to eat more fruits, vegetables, grains, [and] beans, most of the time,” she said. “You can work your favorite foods in and still eat a very brain-healthy way.”