Peanuts could be doing more than satisfying a mid-afternoon craving. New research suggests they may also help support brain health in older adults, improving blood flow to key areas of the brain and offering a modest lift to memory.
Researchers at the NUTRIM Institute at Maastricht University Medical Center in the Netherlands recruited 31 healthy adults aged 60 to 75 and guided them through two study phases. Participants spent 16 weeks eating 60 grams of unsalted, skin-roasted peanuts every day, followed by 16 weeks of avoiding peanuts entirely, with an eight-week break in between.
The team tracked changes using MRI scans and memory tests, and the results were unexpectedly impressive. After the peanut-eating period, global cerebral blood flow increased by 3.6 percent, with even stronger gains in key grey-matter regions involved in memory and decision-making. The brain’s frontal and temporal lobes, which are crucial for language and higher-level thinking, also showed improved vascular activity.
Dr. Peter Joris said the findings point to meaningful changes in brain circulation. “We found that longer-term consumption of unsalted, skin-roasted peanuts improved global cerebral blood flow, which suggests an overall enhancement in brain vascular function,” he explained.
- Memory also saw a modest boost. Participants scored 5.8 percent better on verbal memory tests, although reaction time and executive function showed little change.
- The benefits extended beyond the brain. Systolic blood pressure and pulse pressure dipped slightly, hinting at broader cardiovascular support.
Peanuts are rich in unsaturated fats, fibre, polyphenols, and plant protein, and they are especially high in L-arginine, an amino acid known to support blood vessel health. Keeping the skins on during roasting also preserves antioxidants, which may further benefit vascular function.
Still, researchers caution against over interpreting the findings. The study was small and focused on healthy older adults, meaning the results may not apply to other age groups, health conditions, or different forms of peanuts. Participants were also likely aware of when they were consuming peanuts, so a placebo effect cannot be ruled out.