Dose Response Relationship Between Fat Ingestion and Metabolism (AFDR)

Investigating the Effect of Acute Fat Ingestion on Glucose Metabolism in Young Healthy Adults: a Dose Response Study

The goal of this clinical trial is to compare features of metabolism in healthy, young adults after they consume four meals of differing fat quantity. The main question this trial aims to answer is how does increasing fat quantity impact glucose tolerance, glucose and insulin metabolism, and hormones involved in hunger. Participant will consume four meals consisting of either 20, 40, 60, or 80% energy from fat.

Study Overview

• Status: Completed
• Conditions: Glucose Tolerance Impaired
• Intervention / Treatment: Other: 20% fat meal; Other: 40% fat meal; Other: 60% fat meal; Other: 80% fat meal

Detailed Description

The long-term consumption of high-fat foods can lead to unhealthy changes in the functioning of the body, giving rise to metabolic diseases such as type 2 diabetes. Similarly, short-term high-fat diets have also been shown to disrupt how the body performs but there is a lack of information regarding how a single high-fat meal can disrupt metabolism. Comparing meals of different fat quantity, without changing the overall energy intake (calories), will help us understand the short-term effect of fat ingestion on the functioning of the body and whether increasing the amount of fat in a meal is related to the level of dysfunction in the body. Therefore, the investigators will provide participants with four meals of varying fat quantity and in the period following the meal, the investigators will take blood samples to determine any changes that occur in the body in response to different levels of fat.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Hamilton, Ontario, Canada, L8S 3X3
      • McMaster University, Ivor Wynne Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• BMI between 18.5 and 30.0 kg/m2
• Weight stable for the past 6 months (± 2kg)
• VO2max values within a below average to above average range (38-50 mL/kg and 35-47 mL/kg for 18-25 year old males and females respectively. 35-48 mL/kg and 34-45 mL/kg for 26-35 year old males and females respectively)
• Fasting blood glucose <6.0 mM
• Resting blood pressure <140/90 mmHg
• Taking second generation oral contraceptives (females only)

Exclusion Criteria:

• Smoking
• Diabetes, cancer, or other metabolic disorders
• Cardiac or gastrointestinal problems
• Infectious disease
• Barium swallow or nuclear medicine scan in the previous 3 weeks
• Follow a strict vegan diet
• Pregnant or breastfeeding (females only)
• Diagnosis of polycystic ovary syndrome (females only)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 20% fat meal; This meal will contain 15 kcal/kg of body weight and consist of 20% fat, 65% carbohydrates, and 15% protein.	Other: 20% fat meal; Provided to participants once throughout duration of study, contains 20% fat
Experimental: 40% fat meal; This meal will contain 15 kcal/kg of body weight and consist of 40% fat, 45% carbohydrates, and 15% protein.	Other: 40% fat meal; Provided to participants once throughout duration of study, contains 40% fat
Experimental: 60% fat meal; This meal will contain 15 kcal/kg of body weight and consist of 60% fat, 25% carbohydrates, and 15% protein.	Other: 60% fat meal; Provided to participants once throughout duration of study, contains 60% fat
Experimental: 80% fat meal; This meal will contain 15 kcal/kg of body weight and consist of 80% fat, 5% carbohydrates, and 15% protein.	Other: 80% fat meal; Provided to participants once throughout duration of study, contains 80% fat

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose tolerance	A 2-hour intravenous glucose tolerance test will be performed 4-hours after meal consumption	Two hours (taking place following the 4-hour postprandial period)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose and lipid metabolites	Postprandial availability of glucose (mM)	During the 4-hour postprandial period
Glucose and lipid metabolites	Postprandial availability of insulin (µIU/mL)	During the 4-hour postprandial period
Glucose and lipid metabolites	Postprandial availability of total cholesterol (mmol/L)	During the 4-hour postprandial period
Glucose and lipid metabolites	Postprandial availability of low-density lipoprotein (mmol/L)	During the 4-hour postprandial period
Glucose and lipid metabolites	Postprandial availability of high-density lipoprotein (mmol/L)	During the 4-hour postprandial period
Glucose and lipid metabolites	Postprandial availability of non-esterified fatty acids (mmol/L)	During the 4-hour postprandial period

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hunger hormones	Postprandial concentration of ghrelin (pmol/L)	During the 4-hour postprandial period
Hunger hormones	Postprandial concentration of leptin (pmol/L)	During the 4-hour postprandial period
Hunger hormones	Postprandial concentration of adiponectin (pmol/L)	During the 4-hour postprandial period

Collaborators and Investigators

• Sponsor: McMaster University

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2023
• Primary Completion (Actual): April 30, 2024
• Study Completion (Actual): April 30, 2024

Study Registration Dates

• First Submitted: March 11, 2023
• First Submitted That Met QC Criteria: June 14, 2023
• First Posted (Actual): June 15, 2023

Study Record Updates

• Last Update Posted (Actual): August 19, 2025
• Last Update Submitted That Met QC Criteria: August 14, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: Insulin; Nutrition; Glucose; Metabolism; High-fat
• Additional Relevant MeSH Terms: Metabolic Diseases; Glucose Metabolism Disorders; Hyperglycemia; Glucose Intolerance
• Other Study ID Numbers: 16153

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD will not be available to other researchers

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No