Effects of Daily Almond Consumption on Glycemia in Adults with Elevated Risk for Diabetes: A Randomized Controlled Trial

Abstract

The purpose of this study was to examine the potential for sustained almond consumption to reduce HbA1c concentrations among individuals with elevated values. A 16-week randomized, parallel-arm, controlled trial was conducted. Eighty-one adults with elevated HbA1c concentrations (>5.7%) were randomly assigned to incorporate 2 oz of raw almonds (A: n=39) or energy-matched snacks (C: n=42) into their daily diets. Body weight, body composition, plasma lipids, HbA1c, plasma vitamin E, glycemia (by meal tolerance test and continuous glucose monitoring), dietary intake, and hedonic responses to test foods were measured at stipulated time points. Participants consuming almonds ingested 253 kcal/d more than participants in the control group (P=0.02), but this did not result in a significant difference in body weight. No statistically significant differences were observed in HbA1c concentrations, blood chemistries, body composition, or glycemia over time or between groups. However, Healthy Eating Index scores improved within the almond group as compared to the control group (P<0.001). Additionally, the hedonic rating of almonds within the almond group did not decline as markedly as the control group’s reduced liking of the pretzel snack. Alpha-tocopherol increased significantly, and gamma tocopherol tended to decrease in the almond group, indicating compliance with the dietary intervention. Overall, daily ingestion of 2oz of raw almonds in a self-selected diet for 16 weeks did not alter short-term or longer-term glycemia or HbA1c concentrations in adults with elevated HbA1c concentrations, but they were well-tolerated hedonically and improved diet quality without promoting weight gain.