Effects of Almonds on Glycemia in Adults With Elevated Hemoglobin A1c Concentrations

This study will examine the effects of regular almond consumption by individuals with elevated HbA1c on long-term glycemic control.

Study Overview

• Status: Active, not recruiting
• Conditions: Glucose Intolerance; Glucose Metabolism Disorders (Including Diabetes Mellitus)
• Intervention / Treatment: Other: Almond; Other: Control

Detailed Description

Globally, it is projected that 418 million people will have impaired glucose tolerance by 2025. In the US, an estimated 34 million Americans have diabetes and 88 million, 33% of adults, have pre-diabetes. Impaired glucose tolerance is now manifesting in young adults where 20% of those 12-18 years of age have prediabetes. The current prevalence of Type 2 diabetes is over 8%, but it is projected that up to a third of Americans will develop diabetes in their lifetime. Additionally, the total annual cost of diabetes is approximately $327 which accounts for 25% of all US health care costs. Moreover, the costs rose 60% from 2007 to 2017 and this trend is continuing.

Diet is the preferred approach for management for this diet-related chronic disorder. Accumulating evidence suggests almond consumption decreases postprandial glycemia and may evoke a second meal effect, especially when they are consumed at breakfast or as an afternoon snack, which may aid in long-term glycemic control. Additionally, almond consumption can decrease total and LDL cholesterol, resulting in lower peripheral insulin resistance and cardiometabolic complications from type 2 diabetes mellitus. However, there is mixed evidence on the effects of almond consumption on HbA1c, a clinically important endpoint that provides a reliable measure of long-term glycemia and is correlated with risk of complications from diabetes. Thus, the investigators hypothesize a beneficial effect of regular almond consumption on long-term glycemic control in individuals with elevated baseline HbA1c.

• Study Type: Interventional
• Enrollment (Estimated): 84
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Li-Chu Huang; Email: huan1472@purdue.edu

Study Locations

• United States
  • Indiana
    • West Lafayette, Indiana, United States, 47907
      • Purdue Univeristy

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• HbA1c >5.7%
• BMI >20 kg/M^2
• Prefer no use of medications, but if on medication, must have been on a stable dose for 3 months and plan to remain at the same level for the duration of the trial.
• Healthy, good dentition
• No nut allergies
• >4.0 eating events per day
• >=1 low nutrient density snack/d
• No allergy to chocolate

Exclusion Criteria:

• HbA1c within normal range
• BMI <20 kg/M^2
• Nut allergies
• Smoker
• Pregnant

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Almond Group; Participants will consume almonds every day for 16 weeks, but will not be allowed to consume any other nuts or nut products.	Other: Almond; Participants will consume almonds every day for 16 weeks.
Experimental: Control Group; Participants will consume pretzels every day for 16 weeks, but will not be allowed to consume any other nuts or nut products.	Other: Control; Participants will consume pretzels every day for 16 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
HbA1c		Baseline
Change in HbA1c	HbA1c % change	16 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose response to a meal tolerance test	mg/dl	Baseline and week 16
Insulin response to a meal tolerance test	mmol/L	Baseline and week 16
Chronic glycemia	mg/dl	Baseline, week 8 and week 16
Food intake	kcal	Two days (one week day and one weekend day) at screening, week 8 and week 16.
Body weight	Kilograms (kg)	Screening, baseline, week 4, week 8, week 12, and week 16
Body composition	Percentage (%)	Baseline, week 16
Hedonic survey	mm on a VAS	Baseline, week 4, week 8, week 12. week 16

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Compliance - Vitamin E	mg/L	Baseline, week 8 and week 16.
Compliance - fatty acid profile	% fatty acid composition	Baseline, week 8 and week 16

Collaborators and Investigators

• Sponsor: Purdue University
• Collaborators: Almond Board of California
• Investigators: Principal Investigator: Richard D Mattes, PhD, Purdue University

Study record dates

Study Major Dates

• Study Start (Actual): February 9, 2022
• Primary Completion (Actual): July 30, 2023
• Study Completion (Estimated): May 30, 2024

Study Registration Dates

• First Submitted: November 23, 2021
• First Submitted That Met QC Criteria: January 3, 2022
• First Posted (Actual): January 4, 2022

Study Record Updates

• Last Update Posted (Estimated): December 12, 2023
• Last Update Submitted That Met QC Criteria: December 11, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Hyperglycemia; Glucose Intolerance; Metabolic Diseases; Glucose Metabolism Disorders
• Other Study ID Numbers: 055-055

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No