Clinical trial NCT03236116: Almond Consumption and Glycemia
Official title: Almond Consumption and Glycemia
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Glucose Intolerance
Appetite Disorders
Glucose Metabolism Disorders (Including Diabetes Mellitus)
Lipid Metabolism Disorder
Lead sponsor: Purdue University
Sponsor class: OTHER
Collaborators: name: Almond Board of California
First posted: 2017-08-01
Enrollment: 75
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: This study will examine the effects of almonds consumed by adults with different body fat distributions on indices of carbohydrate and lipid metabolism.

Detailed description: There is considerable evidence supporting a causal role for truncal visceral fat depots in glucose dysregulation. Individuals with large visceral fat depots have impaired suppression of free fatty acid release in response to insulin, elevated triglycerides and low concentrations of high density lipoprotein cholesterol. The high free fatty acid concentration may induce insulin resistance in the muscle and liver. There is more recent evidence that truncal subcutaneous fat depots are also problematic, though this literature is mixed. In contrast, gluteo-femoral fat depots have not been implicated in insulin resistance and dysregulation of carbohydrate metabolism. Failure to account for differences in the contributions of these depots will add noise to measurements of dietary interventions to mitigate glucose dysregulation. Previous studies have reported evidence indicating acute and chronic consumption of almonds improves glycemia. Acute effects are important indicators of health benefit, but longer-term trials, ones permitting identification of the effects of a dietary intervention on HbA1c, are more telling and clinically relevant. To more definitively establish the association between almond consumption and improved carbohydrate metabolism, we propose a six-month trial that contrasts the effects of almond consumption at optimal times of the day versus consumption of low nutrient dense snack foods on indices of carbohydrate metabolism, food intake and appetite in adults characterized by three distinct fat depots.

Participants will consume either almonds, or no nuts every day for 6 months. At baseline, participants will be weighed and undergo a DEXA scan to determine body fat composition and will be assigned a group. Blood will also be collected fasted and at stipulated times in response to a meal tolerance test to measure insulin, glucose, C-peptide, HbA1c, lipid panel, gut peptides, and compliance to the diet. Participants will be given links to complete appetite ratings and record food intake. Participants will report to the lab every two weeks to be weighed, and get a resupply of almonds (if in the almond group). At the two-week mark on months 2 and 4, participants will be weighed, blood will be taken to assess compliance to the diet, and links will be given to complete appetite ratings and record food intake. At month 6, all measurements from baseline will be repeated.

Eligibility criteria: Inclusion Criteria:

* Meeting one of the following body fat distribution criteria determined by DEXA: 1. High visceral fat 2. High gluteo-femoral fat 3. High truncal subcutaneous fat
* 18-60 years
* no nut allergies

Exclusion Criteria:

* Not meeting one of the body fat distribution criteria
* allergic to nuts

Primary outcomes:
measure: HbA1c
timeFrame: Baseline
measure: fasting glucose
timeFrame: Baseline
measure: fasting triglycerides
timeFrame: Baseline
measure: Change in Body weight
timeFrame: Every two weeks for 6 months.
measure: Body composition
timeFrame: Baseline
measure: GLP-1
timeFrame: Baseline
measure: Change in HbA1c
timeFrame: 6 months
measure: Change in fasting glucose
timeFrame: 6 months
measure: fasting triglycerides
timeFrame: 6 months
measure: Change in Body composition
timeFrame: 6 months
measure: Change in GLP-1
timeFrame: 6 months
measure: fasting insulin
timeFrame: Baseline
measure: total cholesterol
timeFrame: Baseline
measure: LDL-cholesterol
timeFrame: Baseline
measure: HDL-cholesterol
timeFrame: Baseline
measure: GIP
timeFrame: Baseline
measure: change in fasting insulin
timeFrame: 6 months
measure: change in total cholesterol
timeFrame: 6 months
measure: change in LDL-cholesterol
timeFrame: 6 months
measure: change in HDL-cholesterol
timeFrame: 6 months
measure: change in GIP
timeFrame: 6 months
measure: C-peptide
timeFrame: baseline
measure: C-peptide
timeFrame: 6 months
measure: Homa-IR
timeFrame: baseline
measure: Homa-IR
timeFrame: 6 months
measure: Homa-Percent Beta
timeFrame: Baseline
measure: Homa-Percent Beta
timeFrame: 6 months
Secondary outcomes:
measure: Diet Quality
timeFrame: Three days (two non-consecutive week days and one weekend day) at baseline, month 2, 4, and 6.
measure: Compliance
timeFrame: Baseline, month 2, 4, and 6.
Other outcomes:
Locations:
city: Indianapolis
country: United States
facility: Indiana University School of Medicine
state: Indiana
city: West Lafayette
country: United States
facility: Purdue University
state: Indiana
city: West Lafayette
country: United States
facility: Purdue University
state: Indiana
Study officials:
affiliation: Purdue University
name: Richard D Mattes, PhD
role: PRINCIPAL_INVESTIGATOR
References: