This Is the Best Diet for Cognitive Health

Brain health has gotten more attention these days—and for good reason. Your brain is the master control panel for every process in your body. If your brain isn’t healthy, it will affect the rest of your body. And a huge part of your brain health is cognition, or your brain’s ability to perceive, conceive, remember, reason, judge, imagine and problem solve.

As of 2022, about 4% of Americans were diagnosed with dementia, which affects cognition. An estimated 7.2 million Americans age 65 and older are currently living with Alzheimer’s disease, the most common type of dementia. While the risk of dementia increases with age, it can occur in younger people, too. Researchers believe that about 200,000 Americans between the ages of 30 and 64 are currently living with younger-onset dementia.

While genetics plays a role in dementia, there’s a significant lifestyle component as well. Researchers from China examined the relationship of several eating patterns to dementia and death from Alzheimer’s disease. They recently published their findings in The Journal of Prevention of Alzheimer’s Disease. Let’s break them down.

How Was This Study Conducted?

Researchers drew their data from a previously conducted long-term U.S. study called NHANES—National Health and Nutrition Examination Survey. There were two parts to their analysis. The first was to examine relationships between eating patterns and death (mortality) from Alzheimer’s disease. For this analysis, there were more than 27,000 participants. The second part examined the link between the same eating patterns and mild cognitive impairment. This analysis included around 2,700 participants. The average age of participants was 60, with just over half of them being female. 

Dietary intake was assessed based on one or an average of two 24-hour recalls—meaning that the participants told researchers what they had eaten in the last day. From this, researchers calculated dietary pattern scores based on five different eating patterns: the Healthy Eating Index (HEI-2015), the alternate Mediterranean diet (aMED), Dietary Approaches to Stop Hypertension (DASH), the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) and Healthful Plant-based Diet Index (hPDI). 

Since the primary outcome of this study was to examine Alzheimer’s disease mortality, researchers used death certificates to determine the cause of death. The secondary outcome they were testing was mild cognitive impairment, which was determined via cognitive testing. Specifically, they used tests that assessed memory, verbal fluency and executive function, which includes higher-level cognitive skills used to control and coordinate other abilities and behaviors. 

What Did This Study Show?

After running several statistical analyses, including adjusting for factors that may influence brain health (like sex, age, physical activity, smoking and alcohol use), the main finding of this study was that the Mediterranean diet showed the strongest relationship to Alzheimer’s disease mortality. 

Specifically, the researchers observed that higher alternative-Mediterranean diet (aMED) scores were associated with a 28% lower risk of dying from Alzheimer’s disease and 31% lower odds of having mild cognitive impairment when compared to those with the lowest aMED scores.

When comparing the highest to the lowest scores of other healthy eating patterns—including the MIND diet, the healthy eating index and the plant-based diet—they showed 11% to 19% lower odds of mild cognitive impairment.

Overall, researchers state that their findings suggest the importance of healthy eating patterns for maintaining cognitive health. 

As with any study, there were a few limitations to this one. First, researchers relied on 24-hour dietary recalls to determine eating patterns. Recalling what you ate the previous day leaves plenty of room for error, not just in what you ate, but also how much. Plus, one day of eating might not be a good representation of your long-term eating pattern. 

Researchers also state that using Alzheimer’s disease death rates might underestimate the incidence of Alzheimer’s disease, since some people with Alzheimer’s could die from another cause. Lastly, because the study population used only Americans, it is unknown if these results can also be extended to other populations. 

How Does This Apply to Real Life?

It’s no secret that we love the Mediterranean diet around here. And we’re not the only ones. This healthy eating pattern has been ranked the healthiest diet for eight years in a row. And the DASH and MIND diets aren’t far behind. 

These types of eating patterns prioritize nutrient-dense foods, including fruits, vegetables, whole grains, nuts, seeds, legumes and healthy fats from olive oil and fish. They also limit added sugars, ultra-processed foods, processed meats and refined grains. Plus, they’re flexible. You can adapt them to your lifestyle and preferences—no scales or specialty foods necessary.

We’ve got lots of Mediterranean diet meal plans and recipes to make it easy for you to start incorporating more of the foods common to this eating pattern. If you’re totally new to this type of eating, our 7-Day Mediterranean Diet Meal Plan for Beginners is a great place to start. When you’re ready for more, give our 30-Day Mediterranean Diet Meal Plan for Healthy Aging a go. 

Other habits also influence brain health. Getting plenty of quality sleep tops the list, as does moving your body more often and taking time out to chill and rest. Taking a whole-health approach to healthy aging can be a wise way to improve your overall health.

The Bottom Line

This study adds to the growing body of evidence that healthy eating patterns, like the Mediterranean diet, may help protect your brain from dementia. It also suggests that regularly including foods common in the Mediterranean diet may help reduce the risk of dying from Alzheimer’s disease if you do eventually develop the condition, though more research needs to be done. 

Other habits that have been shown to help keep your brain healthy include regular physical activity, managing factors causing chronic stress, getting plenty of quality sleep and spending time with loved ones. Choose one of these areas to start working on today and progressively build in more habits over time to help protect your brain as you age.