Small trial finds changes in brain insulin responsiveness after 16 weeks of unsalted peanut consumption.
By SPEAKIN’ OUT NEWS
An everyday snack is giving scientists another reason to investigate the relationship between food and the aging brain. A small clinical trial found that eating unsalted, skin-roasted peanuts affected insulin responsiveness in brain regions involved in memory.
Researchers at Maastricht University Medical Center in the Netherlands studied 31 healthy older adults. Participants completed a 16-week peanut period and a no-peanut comparison period, separated by an eight-week break. During the peanut phase, they consumed 60 grams daily, approximately two servings.
The study, published in Food & Function, used MRI scans to examine brain blood-flow responses after insulin was administered through the nose. Researchers detected a potentially beneficial response in one cluster of brain regions. Measures of liver fat and circulating glucose, lipid and inflammation markers did not change.
“The hormone insulin plays an important role in the brain, where it supports memory and other cognitive processes,” senior author Dr. Peter Joris said in a release distributed by The Peanut Institute.
The release explained that insulin supports nerve-cell survival and communication. It also described peanuts’ mix of unsaturated fats, fiber and other nutrients as possible contributors, rather than identifying one ingredient responsible for the findings.
The Peanut Institute Foundation funded the study. The release states that the funder did not participate in study design, implementation, analysis, interpretation or manuscript preparation.
The findings received November 1 news coverage, but the research predates that report. Its small sample and brain-imaging outcome do not establish that peanuts prevent dementia or Alzheimer’s disease.
Nor does the trial establish equivalent benefits from peanut butter or sweetened peanut products. The tested food was specifically unsalted, skin-roasted peanuts, and larger studies are needed before drawing broader conclusions.