Daily consumption of 60 grams of roasted peanuts improves insulin sensitivity in memory-related brain regions and increases cerebral blood flow among older adults, according to a 16-week intervention study conducted by researchers at Maastricht University Medical Centre and described in the journal Food & Function.
In Plain English: The Clinical Takeaway
- Targeted Brain Response: Eating a daily portion of peanuts enhances how insulin is processed in key areas of the right hemisphere, including the hippocampus, which governs learning and memory.
- Vascular Support: Peanuts deliver L-arginine, an amino acid that helps produce nitric oxide to support blood vessel elasticity and cerebral circulation.
- Dietary Integration: The clinical trial used 60 grams—roughly two small handfuls—of unsalted, skin-on roasted peanuts daily over a 16-week period.
Maastricht University Researchers Track Brain Blood Flow and Insulin Response
Scientists at the Maastricht University Medical Centre tracked 31 healthy volunteers aged 60 to 75 to evaluate how routine peanut consumption alters neural metabolism. Participants consumed 60 grams of unsalted, roasted peanuts with skins daily for 16 weeks, with researchers comparing these metabolic markers against a control period involving zero peanut intake. To measure physiological shifts, the team administered intranasal insulin and utilized specialized arterial spin-labeling magnetic resonance imaging (MRI) scans to map changes in regional brain perfusion.
The imaging data revealed heightened insulin responsiveness across several structures in the right cerebral hemisphere. Affected areas included the posterieure cingulaire gyrus, linguale gyrus, parahippocampale gyrus, and the hippocampus. Because insulin signaling regulates neuronal communication and synaptic plasticity—processes that typically degrade with advanced age—these localized physiological changes highlight a direct link between diet and central nervous system function.
Nutritional Composition and Vascular Mechanisms
The observed neurological benefits stem from the complex nutrient profile packed into whole peanuts. Continental Hospitals noted that peanuts provide unsaturated fats that support neuronal cell membranes, alongside vitamin E to combat oxidative stress, niacin for cerebral metabolism, and magnesium to facilitate nerve signal transmission. Furthermore, the presence of L-arginine supplies the foundational substrate for endothelial nitric oxide synthase, an enzyme critical for vasodilation and adequate blood supply to cognitive centers.
These findings build directly upon a preceding 2025 trial executed by the same research group. That earlier investigation demonstrated that daily peanut intake corresponded with a 5.8 percent improvement in verbal memory scores alongside a 3.6 percent elevation in total cerebral blood flow. Despite these measurable markers, investigators emphasize that the trial did not evaluate or prove any preventative efficacy against dementia or Alzheimer’s disease.
| Trial Parameter | Maastricht University Study Data |
|---|---|
| Cohort Size | 31 healthy participants (aged 60–75) |
| Intervention | 60 grams daily of un-salted, skin-on roasted peanuts |
| Trial Duration | 16 weeks |
| Measured Outcomes | 5.8% verbal memory increase, 3.6% cerebral blood flow increase |
Future Research and Methodological Limitations
Study authors caution that due to the modest sample size of 31 participants, broader clinical generalizations cannot be made regarding neuroprotection against neurodegenerative pathologies. Future longitudinal investigations featuring larger cohorts and extended observation windows remain necessary to verify whether short-term improvements in cerebral insulin sensitivity translate into sustained, long-term cognitive preservation.
References
- Maastricht University Medical Centre. Research published in Food & Function.
- Continental Hospitals. Clinical analysis on dietary fat, L-arginine, and cerebral perfusion.
