Effect of a Low-calorie and High-protein Diet Specially Rich in Animal Protein Compared to a Low-calorie and High-protein Diet Specially Rich in Plant Protein on Glucose Metabolism in Subjects With Prediabetes or Type 2 Diabetes and Overweight or Obesity.

A Randomized Study to Investigate the Effect of a Low-calorie and High-protein Diet Specially Rich in Animal Protein Compared to a Low-calorie and High-protein Diet Specially Rich in Plant Protein on Glucose Metabolism in Subjects With Prediabetes or Type 2 Diabetes and Overweight or Obesity.

The aim of the study is to explore the effect of a low-calorie diet rich in protein (with a content of 35% of the total calories of the diet), mostly coming from animal sources (75% of total protein), compared to a hypocaloric diet rich in protein (with a content of 35% of the total calories of the diet), mostly coming from plant sources (75% of total proteins), in subjects with prediabetes or type 2 diabetes and overweight or obesity, on body composition, glucose and lipid metabolisms, after 6 months of intervention.

To achieve the objective, a nutritional intervention study is carried out by randomizing participants to: a) a hypocaloric and high-protein diet (35% of total calories), mostly of them coming from animal sources (75% of total protein); b) a hypocaloric and high-protein diet (35% of total calories), mostly of them coming from plant sources (75% of total protein). The study has a total duration of 6 months and include the assessment of clinical, anthropometric, biochemical and lifestyle parameters, at the beginning of the study and after 3 and 6 months of intervention.

Study Overview

• Status: Completed
• Conditions: Diabetes Mellitus, Type 2; PreDiabetes; Overweight and Obesity
• Intervention / Treatment: Behavioral: Low-calorie and high-protein diet with the majority of protein coming from animal sources.; Behavioral: Low-calorie and high-protein diet with the majority of protein coming from plant sources.

• Study Type: Interventional
• Enrollment (Actual): 120
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Zaragoza, Spain, 50009
    • Instituto de Investigación Sanitaria Aragón, Hospital Universitario Miguel Servet, Universidad de Zaragoza

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged between 18 and 80.
• BMI between 27.5 kg/m2 and 40 kg/m2.
• Diagnosed as prediabetes or type 2 diabetes according to ADA criteria.
• Informed consent to be signed.

Exclusion Criteria:

• Taking antidiabetic drugs (except for metformin with stable dose in the previous 6 months).
• Taking lipid-lowering drugs in unstable dose in the previous 2 months.
• Taking functional foods (i.e. sterols enriched food) or any other dietary supplement with a significant effect on lipid and glucose metabolism and body weight.
• Uncontrolled type 2 diabetes (i.e. glycated hemoglobin over 8%)
• Any disease that could affect study results (i.e. uncontrolled hypothyroidism).
• Alcohol intake over 30 g/day.
• Pregnancy or breastfeeding.
• Any other condition that investigators consider that could interfere with study outcomes.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High-protein animal diet.; Low-calorie and high-protein diet (35% of total calories), mostly of protein coming from animal sources (75% of total protein).	Behavioral: Low-calorie and high-protein diet with the majority of protein coming from animal sources.; Diet was prescribed to the participant and menus and recipes were also provided.
Experimental: High-protein vegetal diet.; Low-calorie and high-protein diet (35% of total calories), mostly of protein coming from plant sources (75% of total protein).	Behavioral: Low-calorie and high-protein diet with the majority of protein coming from plant sources.; Diet was prescribed to the participant and menus and recipes were also provided.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose change.	Glucose change assessed by difference in fasting glucose concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Glycated hemoglobin change.	Glycated hemoglobin change assessed by difference in glycated hemoglobin concentration (%) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Insulin change.	Insulin change assessed by difference in fasting insulin concentration (UI/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
HOMA-IR change.	HOMA-IR change assessed by difference in HOMA-IR concentration (absolute units and %) comparing 3 and 6 months visits with respect to baseline. HOMA-IR is calculated by calculating: [(fasting glucose (mg/dL) x 0,0555) x fasting insulin (UI/ml)] ÷ 22,5.	After 3 and 6 months of intervention.
Body fat mass change.	Body fat mass change assessed by difference in fat mass (%) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Fat-free mass change.	Fat-free mass change assessed by difference in fat free-mass (%) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Visceral fat mass change.	Visceral fat mass change assessed by difference in visceral fat mass (kg and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total cholesterol change.	Total cholesterol change assessed by difference in fasting total cholesterol concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
LDL cholesterol change.	Total LDL cholesterol change assessed by difference in fasting LDL cholesterol concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
HDL cholesterol change.	HDL cholesterol change assessed by difference in fasting HDL cholesterol concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Triglycerides change.	Triglycerides change assessed by difference in fasting triglycerides concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
C-reactive protein change.	C-reactive protein change assessed by difference in fasting C-reactive protein concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Liver enzymes change.	Liver enzymes (GGT, GOT and GPT) change assessed by difference in fasting liver enzymes concentration (U/L and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Uric acid change.	Uric acid change assessed by difference in fasting uric acid concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
GLP-1 change.	GLP-1 change assessed by difference in fasting GLP-1 concentration (pg/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
GIP change.	GIP change assessed by difference in fasting GIP concentration (pg/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
IL-6 change.	IL-6 change assessed by difference in fasting IL-6 concentration (pg/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
Leptin change.	Leptin change assessed by difference in fasting leptin concentration (pg/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
MCP1 change.	MCP1 change assessed by difference in fasting MCP1 concentration (pg/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.
TNF-alpha change.	TNF-alpha change assessed by difference in fasting TNF-alpha concentration (pg/mL and %) comparing 3 and 6 months visits with respect to baseline.	After 3 and 6 months of intervention.

Collaborators and Investigators

• Sponsor: Universidad de Zaragoza

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2021
• Primary Completion (Actual): October 1, 2022
• Study Completion (Actual): November 1, 2022

Study Registration Dates

• First Submitted: July 1, 2022
• First Submitted That Met QC Criteria: July 8, 2022
• First Posted (Actual): July 13, 2022

Study Record Updates

• Last Update Posted (Actual): November 8, 2022
• Last Update Submitted That Met QC Criteria: November 6, 2022
• Last Verified: November 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Overnutrition; Nutrition Disorders; Body Weight; Hyperglycemia; Diabetes Mellitus; Diabetes Mellitus, Type 2; Obesity; Prediabetic State; Glucose Intolerance; Overweight
• Other Study ID Numbers: PI19/485

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