295: Impacts of Boiled or Roasted Peanuts on Glycemic Response in Acute and Chronic Trials

Introduction

Peanuts are known as a high protein food with a low glycemic index and glycemic load. Boiled peanuts are widely eaten in the American South, which has the highest regional prevalence of diabetes in the nation. Reis et al. found that consumption of peanut butter resulted in a lower glycemic response than raw peanuts. This study measured the impact of peanut preparation methods on glycemic response. Hypotheses explaining an effect of peanuts on glycemic load of a diet involve the fat and fiber content or different amounts of destruction or activation of bioactive compounds in boiled or roasted peanuts.

Methods

14-17 subjects completed five glucose tolerance tests (GTT) over the course of 11 weeks, with two phases: acute and chronic. Each test was conducted after ≥8 hours of fasting and consisted of 10 blood glucose samples taken at 10 to 30 min intervals over two hours. The first test used a glucose drink to establish a personal baseline. The two acute tests were conducted immediately after consumption of roasted or boiled peanuts in addition to the glucose drink. The two chronic trials consisted of a two-week period of daily consumption of boiled peanuts or roasted peanuts, with a week-long washout between trials, followed by a GTT.

Results

Compared to the baseline GTT data, none of the four trials showed a significantly different glycemic response (p > 0.05). However, the mean (±SEM) net incremental area under the curve (NetiAUC) of the baseline test, the acute boiled trial, the acute roasted trial, the chronic boiled trial, and the chronic roasted trial were 5172±446, 4535±485, 3983±666, 4379±586, and 5235±404 min*mg/dL respectively, demonstrating high variation among the participants. There is a repeatable significant variation among individuals, with high coefficients of variation (CV) for each GTT (32%, 44%, 67%, 50%, and 29% respectively).

Significance

Boiling or roasting peanuts showed no significant effect on glycemic response when compared to each other or the no-peanut control with either immediate or daily intake. The high CV among subjects could be due to diet, BMI, or physical activity. Further research with boiled peanuts as a high-protein staple or snack food is warranted.

Authors: JA Londoño, LL Dean, A Fares, JC Allen