Daily peanuts deliver a surprising brain benefit, scientists discover after 16 weeks of eating them every day

Changes in brain insulin response

After participants ate 60 grams of peanuts each day for 16 weeks, researchers observed improved insulin responsiveness in several regions of the right hemisphere. These included parts of the lingual gyrus, hippocampus, parahippocampal gyrus and posterior cingulate gyrus, which contribute to memory-related processes.

Insulin regulates blood sugar, but it also supports the growth, survival and communication of nerve cells. Healthy insulin signaling may help protect against processes associated with Alzheimer’s disease.

How the study was conducted

The study involved 31 healthy adults between 60 and 75 years old. Researchers used a randomized, controlled crossover design to compare peanut consumption with avoiding peanuts. The team used arterial spin labeling MRI to measure blood flow in brain regions, then tracked changes after insulin was administered through the nose. Abdominal MRI assessed liver fat, while cognitive abilities were tested using the Cambridge Neuropsychological Test Automated Battery.

Earlier findings and possible nutrients

The results build on research published by study senior author Peter Joris in 2025. That earlier study reported a 3.6% increase in overall cerebral blood flow and a 5.8% improvement in verbal memory after 16 weeks of peanut consumption.

Joris said several peanut components may contribute, including unsaturated fats, fiber, vitamins, minerals and bioactive phytochemicals. Peanuts also contain plant-based protein and are rich in L-arginine, a precursor of nitric oxide that has been reported to support learning and memory.

Study setting and publication

The research was conducted by the Institute of Nutrition and Translational Research in Metabolism at Maastricht University Medical Center in the Netherlands. Its findings were published in the peer-reviewed journal Food & Function.

Researchers supplied premeasured packets of skin-roasted peanuts to help keep intake consistent. Participants were asked to eat them in the morning or afternoon and could choose how to fit the serving into their routine.