Daily consumption of unsalted, skin-roasted peanuts may support aspects of brain health in older adults, according to research from Maastricht University Medical Center in the Netherlands. The study found that eating approximately 60 grams of peanuts per day for 16 weeks improved insulin responsiveness in several brain regions involved in memory.

The findings were produced by researchers from the Institute of Nutrition and Translational Research in Metabolism and published in the peer-reviewed journal Food & Function. The study involved 31 healthy adults between 60 and 75 years old and used a randomized, controlled crossover design, allowing participants’ results during the peanut phase to be compared with results during a period in which they avoided peanuts.

Insulin is involved not only in blood sugar regulation but also in brain processes that support the growth, survival and communication of nerve cells. Researchers observed improved insulin responsiveness in regions of the right hemisphere, including parts of the lingual gyrus, Hippocampus, parahippocampal gyrus and posterior cingulate gyrus. These areas contribute to memory-related functions.

The study’s senior author, Peter J. Joris, said that brain responsiveness to insulin can decline with age and has been associated with age-related cognitive deterioration. He said the results suggest that changes in regional brain insulin responsiveness could contribute to potential cognitive benefits associated with unsalted, skin-roasted peanut consumption.

The research builds on an earlier study led by Joris, published in 2025, which reported that 16 weeks of peanut consumption increased overall cerebral blood flow by 3.6% and improved verbal memory performance by 5.8%. Cerebral blood flow reflects the circulation of oxygen and nutrients through the brain and is an indicator of brain vascular health.

To assess the effects of the diet, the researchers used arterial spin labeling magnetic resonance imaging to measure blood flow in different brain regions. They assessed the brain’s response to insulin after administering it through the nose, while abdominal MRI scans were used to measure liver fat. Participants’ cognitive abilities were evaluated with the Cambridge Neuropsychological Test Automated Battery.

The researchers said the potential effects may result from several peanut components rather than one individual nutrient. These include unsaturated fats, dietary fiber, vitamins, minerals and bioactive phytochemicals. Peanuts also provide plant-based protein and are rich in L-arginine, a precursor of nitric oxide that has been associated with learning and memory performance.

Participants received premeasured packets and could eat the peanuts in one portion, divide them during the day or include them in meals. During the control period, they avoided peanuts entirely before switching to the alternative condition after 16 weeks.

The study was funded by The Peanut Institute Foundation. The researchers stated that the foundation did not participate in the study’s design, execution, analysis, interpretation or manuscript preparation.

Sources: ScienceDaily.