Walnuts May Support Brain Function in Older Adults, Study Shows

Eating walnuts could be the ticket to supporting cognitive function in older adults, according to a recent study.

After conducting telephone interviews to assess cognitive status in 3,632 adults ages 65 and older in the U.S., researchers concluded any walnut consumption was associated with higher cognitive ability. The results were published in Public Health Nutrition on July 31.  

“In this study, researchers found walnut consumption—even less than the traditional 1-ounce serving—was associated with greater cognitive scores than in non-walnut eaters,” Natalie Rizzo, MS, RD, a partner with California Walnuts, who funded the study, tells Verywell. 

To assess cognitive status, researchers used the Telephone Interview for Cognitive Status, a short questionnaire that asks basic math, verbal, and reasoning questions. They divided participants' walnut consumption into two categories: none/low intake (0.01-0.08 1-ounce servings per day) versus moderate intake (more than 0.08 1-ounce servings per day).

While results suggest people who reported eating walnuts had greater cognitive scores than those who avoided the nut, it does not prove that walnuts offer a protective effect against cognitive decline.

“This research shows similar results to other studies analyzing walnut consumption and cognitive function,” Rizzo says. “For example, according to an epidemiological study published in The Journal of Nutrition Health & Aging, eating walnuts may improve performance on cognitive function tests for memory, concentration, and information processing speed in adults.”

Walnuts and Brain Health

Walnuts are well-know for their brain-supporting nutrients, including ALA omega-3 fatty acids and polyphenols. They also support healthy blood pressure, which facilitates brain health by helping the heart pump blood to the brain.

This is not the first study that suggests walnut consumption has a positive effect on brain health. Results from other studies suggest:

• Women who consume at least two servings of walnuts per week during their late 50s and early 60s are more likely to age healthfully compared to those who do not eat walnuts. In this study, “healthy aging” was defined as having no chronic diseases, no memory impairment, and no physical disabilities, as well as having "intact mental health" after the age of 65.  
• Eating a Mediterranean diet supplemented with olive oil or nuts (primarily walnuts) is correlated with reduced age-related cognitive decline in an older Spanish population at high cardiovascular risk.
• Eating nuts, like walnuts, along with berries may have beneficial effects for cognitive performance and neurodegeneration in aging.

Is Walnut Consumption A Must When Supporting Cognitive Function?

According to the all current data, walnuts appear to be a brain-boosting superfood. However, the authors of the Public Health Nutrition study note that those who ate more walnuts also tended to exhibit other positive health behaviors that support cognitive health. Therefore, it's uncertain whether walnuts, specifically, boosted cognitive scores, or if the scores can be attributed to the healthier lifestyles of people who happen to eat walnuts.

“This study—in addition to the large body of research available on walnuts and health—proves walnuts are a healthy addition to one's diet,” Elizabeth Shaw, MS, RDN, CPT, a nutrition expert and author of "Air Fryer Cookbook For Dummies" and "Instant Pot Cookbook For Dummies," tells Verywell. "However, I'm hesitant to say based solely on the 3600+ participants in the study that eating walnuts alone promotes cognition."

Like the study authors imply, Shaw thinks a variety of healthy behaviors and a balanced diet are better predictors of cognitive health.

"Walnuts may certainly work synergistically with other foods known to promote cognitive health, like wild blueberries and eggs," Shaw says. "While walnuts may be challenging for some older adults to chew, eggs are easily palatable. They are also one of the most concentrated sources of choline, a B-like vitamin crucial for cognitive health that 90% of Americans don't get enough of.”

So, if you are not a walnut aficionado, don’t feel like you have to force-feed yourself walnut butter every day. Other foods have been shown to play a positive role in cognition too, including fish, eggs, and blueberries.

Relying solely on walnuts for brain health is also not your best bet. Healthcare providers suggest focusing on dietary patterns, such as the Mediterranean diet, instead of one single food to support brain health.