Effects of Daily Almond Consumption on Glycemia In Adults with Elevated Risk for Diabetes
Accumulating evidence suggests a potential role for almond consumption in ameliorating post-prandial glycemia. Yet their effect on HbA1c, an indicator of long-term glycemic control, is mixed. The purpose of this study was to examine the potential of sustained almond consumption to reduce HbA1c concentrations among individuals with elevated HbA1c concentrations. A 16-week randomized, parallel-arm, controlled trial was conducted. Eighty-one adults with elevated HbA1c concentrations (>5.7%) were randomly assigned to incorporate two servings (2 oz) of raw almonds (A group; N=39) or energy-matched snacks (pretzels C group; N=42) into their daily diets. Half of these intervention foods were to be ingested at breakfast and the other half as a replacement for either a mid-morning or mid-afternoon snack. Throughout the intervention period, measurements were made of body weight, body composition, plasma lipids, HbA1c, alpha and gamma-tocopherol, glycemia (by meal tolerance test) and continuous glucose monitoring, dietary intake, and hedonic responses to test foods 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 (A: 0.2kg SEM ±0.5, C: 0.4kg SEM ±0.5); p>0.05). No statistically significant differences were observed in HbA1c concentrations (A: 0.1% SEM ±0.1, C: 0% SEM ±0.1; p>0·05), 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 (A: 8.3 points SEM ±1.9, C: -2.3 points SEM ±2.1; p<0.001). Additionally, the hedonic rating of almonds did not decline within the almond group in comparison to 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 2 oz of raw almonds in a regular 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 and improved diet quality without promoting weight gain.
Funding
Almond Board of California
History
Degree Type
- Doctor of Philosophy
Department
- Nutrition Science
Campus location
- West Lafayette