How Does Eating 60 Grams of Peanuts a Day Affect Brain Function?

A new study suggests that eating 60 grams of unsalted, roasted peanuts with skin daily may improve the brain's response to insulin in healthy older adults. However, it is not yet clear whether this effect can prevent memory loss or dementia.

A new study suggests that daily consumption of 60 grams of unsalted, roasted peanuts with the skin on may improve the brain's response to insulin in healthy older adults. However, it is not yet clear whether this effect can prevent memory loss or dementia.

Insulin is best known for regulating blood glucose, but it also functions in the brain, where it supports processes involved in neuronal survival, communication, and memory. As we age, the brain may become less responsive to insulin, potentially contributing to changes in cognitive function.

In the current study, researchers investigated whether regular peanut consumption could affect the brain's insulin response in the elderly. This trial included 31 healthy adults between 60 and 75 years old.

Participants consumed 60 grams of unsalted, roasted, skinned peanuts per day for 16 weeks or followed a peanut-free control period. Then, after a period of eight weeks, they changed the situation to another state.

Using arterial spin labeling magnetic resonance imaging, the researchers measured changes in cerebral blood flow after nasal insulin administration. They found that peanut consumption effectively affected the response to insulin in a set of brain regions in the right hemisphere, including the lingual gyrus, hippocampus, parahippocampal gyrus, thalamus, and posterior cingulate gyrus. Several of these regions are involved in memory and other cognitive processes.

These findings are based on previous research by the same group, which showed that a 16-week peanut intervention increased cerebral blood flow by 3.6% and improved verbal memory by 5.8%. Improving the brain's insulin response could potentially help explain these cognitive and vascular effects, the researchers said.

"Multiple nutrients in peanuts, including polyunsaturated fats, dietary fiber, vitamins and minerals, and bioactive chemicals, could potentially contribute to the observed brain benefits," Dr. Peter Juris, senior author of the study and assistant professor in the Department of Nutrition and Movement Sciences at Maastricht University Medical Center in the Netherlands, said in a press release.

"Peanuts are also a good source of plant-based protein and are particularly rich in L-arginine, a precursor to nitric oxide (NO) that supports learning and memory," he added.

However, this study has several limitations. The study was small and only included healthy older adults, so the findings cannot prove that eating peanuts prevents cognitive decline or dementia.

Therefore, more research is needed to determine whether these effects persist with long-term peanut consumption and whether similar benefits occur in people with insulin resistance, cognitive impairment, or neurological diseases.