A September study published in Food & Function found that daily peanut consumption may improve how memory-related brain regions respond to insulin in healthy older adults. The research followed 31 people ages 60 to 75 for 16 weeks and used MRI scans to measure changes in the brain.
Food & Function study
Researchers at Maastricht University Medical Center in the Netherlands gave participants 60 grams, or around two servings, of unsalted, skin-roasted peanuts each day. During a control phase, the same participants ate no peanuts. After 16 weeks, the team reported improved insulin responsiveness in memory-related brain regions and about a 4% increase in overall brain blood flow.
The design matters because it tracks the same people through both peanut and no-peanut phases, which helps isolate the dietary change they were testing. But the group was small, and the study involved only healthy adults in a narrow age range, so the findings cannot be stretched to older adults as a whole.
Kellyann Niotis on brain insulin
Kellyann Niotis, a New York-based preventive neurologist, said, "This is an interesting study because we're increasingly recognizing that insulin plays an important role in brain health, not just blood sugar regulation," She added, "Insulin has important functions in the brain, including supporting communication between brain cells and the processes involved in learning and memory."
She also said, "I would not interpret these findings as evidence that peanuts prevent Alzheimer's." That caution matches the study's limit: the researchers did not determine whether the changes could prevent cognitive decline or Alzheimer's disease.
Stanford University view
Christopher Gardner, a nutrition scientist at Stanford University, said increasing fiber is crucial in a healthy diet and recommended eating more fruits, vegetables and minimally processed foods rather than eliminating an entire food group. His view points readers toward the broader diet pattern around the snack, not a single-food fix.
For readers, the practical takeaway is narrow but useful: the study offers an early signal that peanuts may influence brain metabolism in a small group of healthy older adults, yet it does not justify treating peanuts as a proven way to protect memory or prevent Alzheimer's disease.
