MAASTRICHT, THE NETHERLANDS: Eating peanuts daily may offer benefits for brain health in older adults. New research suggests that regular consumption of unsalted, skin-roasted peanuts may influence insulin responsiveness in brain regions involved in memory.
The findings add to research linking peanut consumption with better brain blood flow and certain aspects of memory. However, scientists have not established that peanuts can prevent Alzheimer’s disease.
What New Research Reveals About Peanuts
A study published in Food & Function on October 19, 2026, investigated how daily peanut consumption affects the brain’s response to insulin.
Researchers from Maastricht University Medical Center in the Netherlands examined whether peanuts could influence brain insulin responsiveness in older adults.
Insulin is best known for regulating blood sugar. However, it also has important functions in the brain. It supports nerve cell activity, communication between neurons and memory formation.
As people age, the brain may become less responsive to insulin. Researchers are investigating whether these changes contribute to age-related cognitive decline and conditions such as Alzheimer’s disease.
The new research examined whether regular peanut consumption could influence this process.
How the Study Was Conducted
The randomized, single-blind, controlled crossover study involved 31 healthy older adults. Participants had an average age of 67 years.
They consumed 60 grams of unsalted, skin-roasted peanuts daily for 16 weeks. This amount represents approximately two servings.
After the peanut intervention, participants completed a control period during which they avoided peanuts. The two periods were separated by an eight-week washout period.
The researchers provided peanuts in premeasured packets. Participants could eat them in the morning or afternoon. They could consume the full portion at once or divide it throughout the day.
Researchers used magnetic resonance imaging (MRI) to examine changes in brain blood flow. They also administered insulin through the nose to assess the brain’s response to the hormone.
What Did the Researchers Find?
The researchers identified a change in insulin-related blood flow responses in one region of the right side of the brain.
The measured response was lower following peanut consumption than during the control period. The affected region partly overlapped areas associated with memory, including the hippocampus and para hippocampal gyrus.
The study authors interpreted this pattern as a potentially beneficial change in regional brain insulin responsiveness.
However, the result needs careful interpretation. The researchers did not demonstrate an overall increase in insulin responsiveness throughout the brain. They identified a specific change in the blood flow response to an insulin challenge.
The study also found no significant changes in liver fat, glucose regulation, lipid metabolism or markers of low-grade inflammation.
Importantly, the researchers did not directly test whether participants experienced better memory after this intervention or whether their risk of Alzheimer’s disease changed. (Kerkhof et al., 2026)
The findings were also covered by The Independent, which highlighted the possible relationship between daily peanut consumption and brain health.
Earlier Research Found Memory Benefits
The 2026 research builds on findings previously published by the same Maastricht research team in Clinical Nutrition in 2025.
That research examined brain blood flow and cognitive performance following 16 weeks of daily peanut consumption.
The researchers reported several changes compared with the control period.
Increased brain blood flow: Global cerebral blood flow increased by 3.6%. Blood flow in grey matter increased by 4.5%.
Improved verbal memory: Participants showed a 5.8% improvement in delayed verbal memory performance, equivalent to approximately 1.4 additional words recalled correctly.
Changes in blood pressure: Systolic blood pressure decreased by approximately 5 mmHg, while pulse pressure decreased by 4 mmHg.
However, the study did not find significant benefits in executive function or psychomotor speed. These functions include planning, decision-making, attention and the speed of physical responses.
The researchers suggested that improved blood circulation could help explain the observed memory benefits.
These findings are encouraging, but they came from a small group of healthy older adults. They do not establish that peanuts prevent memory disorders.
The 2025 and 2026 publications report different outcomes from the same research program. They should not be treated as independent clinical confirmations. (Kerkhof et al., 2025)
Why Peanuts May Support Brain Health
Peanuts contain several nutrients that may contribute to healthy brain function. Researchers believe their combined effects could be more important than any single nutrient.
1. Healthy Unsaturated Fats
Peanuts contain monounsaturated and polyunsaturated fats.
These fats support cardiovascular health when they replace foods high in saturated fats. Healthy blood vessels help maintain adequate circulation throughout the body, including the brain.
The brain requires a continuous supply of oxygen and nutrients. Healthy circulation helps deliver these essential materials to brain cells.
2. L-Arginine and Nitric Oxide
Peanuts are a good source of plant-based protein and the amino acid L-arginine.
The body uses L-arginine to produce nitric oxide, a molecule that helps blood vessels relax and regulate blood flow.
Nitric oxide also plays a role in biological processes involved in learning and memory.
Researchers believe this pathway may contribute to the potential brain benefits associated with peanut consumption. However, the clinical trial did not establish that L-arginine was responsible for the observed changes.
3. Antioxidants and Plant Compounds
Peanuts contain bioactive phytochemicals, including polyphenols.
These plant compounds have antioxidant properties. They help protect cells from oxidative stress, which can damage cellular structures.
Oxidative stress is also being investigated in relation to age-related brain changes and neurodegenerative conditions.
The peanut studies did not isolate the effects of individual antioxidants. More research is needed to understand their contribution to brain health.
4. Fiber, Vitamins and Minerals
Peanuts also provide dietary fiber, vitamins and minerals.
These nutrients support several normal body functions, including energy metabolism, nerve function and general health.
Their nutritional value makes peanuts a useful part of a varied diet. However, their individual effects on Alzheimer’s disease remain unproven.
Do All Peanut Studies Show Benefits?
Not all clinical research has reported improvements in cognitive performance.
A separate randomized controlled trial published in Frontiers in Nutrition in August 2026 examined peanut consumption in older adults who had memory complaints and cardiovascular risk factors.
The researchers enrolled 30 overweight or obese older adults. The final analysis included 27 participants.
The intervention group consumed between 42 and 86 grams of peanuts or peanut butter daily for 12 weeks. The control group avoided peanuts.
Researchers assessed memory, other cognitive abilities and brain activity using functional MRI.
The results showed no significant differences between the peanut and control groups in cognitive performance or task-related brain activation.
This study involved a different population and intervention from the Maastricht research. Its findings do not cancel out the earlier results, but they show that cognitive benefits cannot be assumed for every group of older adults.
Larger trials involving different populations are necessary to understand whether peanuts produce consistent benefits. (Chiriac et al., 2026)
Can Peanuts Prevent Alzheimer’s Disease?
The current evidence does not establish that eating peanuts prevents Alzheimer’s disease.
Alzheimer’s is a progressive brain disorder associated with the accumulation of abnormal amyloid-beta plaques and tau protein tangles. These changes disrupt communication between nerve cells and contribute to the gradual loss of cognitive function.
Researchers are also investigating the roles of insulin signaling, inflammation, oxidative stress and reduced brain blood flow in cognitive decline.
The peanut research provides useful information about some of these biological processes. However, improvements in blood flow or insulin-related responses do not automatically translate into a lower risk of Alzheimer’s disease.
The National Institute on Aging explains that no individual food has been proven to prevent Alzheimer’s disease or age-related cognitive decline.
A healthy dietary pattern may support overall brain health, but it should not be considered a treatment or guaranteed prevention strategy. (National Institute on Aging)
How to Include Peanuts in Your Diet
The Maastricht researchers used 60 grams of unsalted, skin-roasted peanuts daily. This was the research amount, not an established medical recommendation.
People who enjoy peanuts can include them as part of a balanced diet.
Practical choices include:
- Unsalted, skin-roasted peanuts with their skins.
- Peanuts added to salads or meals.
- A small portion of peanuts as a snack.
- Peanuts without added sugar or excessive salt.
Peanuts are energy-dense, so portion sizes should fit individual nutritional needs.
People with peanut allergies must avoid them because allergic reactions can be severe. Those with specific dietary restrictions should seek advice from a qualified healthcare professional.
Conclusion
Daily peanut consumption may support certain aspects of brain health in older adults. Research from Maastricht University Medical Center found changes in regional brain insulin responsiveness, while an earlier analysis reported improved brain blood flow and a modest benefit in delayed verbal memory.
However, the studies involved small groups and relatively short intervention periods. Other research has not found significant improvements in cognitive performance among older adults with memory complaints.
Peanuts can provide healthy fats, protein, fiber and other important nutrients. Including them in a balanced diet may support general health, but they should not be considered a way to prevent or treat Alzheimer’s disease.
Further research involving larger populations and longer follow-up periods is needed to establish their long-term effects on memory and cognitive health.
