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.

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05456347

Enrollment

120

Registered

2022-07-13

Start date

2021-07-01

Completion date

2022-11-01

Last updated

2022-11-08

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Diabetes Mellitus, Type 2, Overweight and Obesity, PreDiabetes

Brief summary

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.

Interventions

BEHAVIORALLow-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.

BEHAVIORALLow-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.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 80 Years

Healthy volunteers

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.

Design outcomes

Primary

Measure	Time frame	Description
HOMA-IR change.	After 3 and 6 months of intervention.	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.
Body fat mass change.	After 3 and 6 months of intervention.	Body fat mass change assessed by difference in fat mass (%) comparing 3 and 6 months visits with respect to baseline.
Fat-free mass change.	After 3 and 6 months of intervention.	Fat-free mass change assessed by difference in fat free-mass (%) comparing 3 and 6 months visits with respect to baseline.
Visceral fat mass change.	After 3 and 6 months of intervention.	Visceral fat mass change assessed by difference in visceral fat mass (kg and %) comparing 3 and 6 months visits with respect to baseline.
Glucose change.	After 3 and 6 months of intervention.	Glucose change assessed by difference in fasting glucose concentration (mg/dL and %) comparing 3 and 6 months visits with respect to baseline.
Glycated hemoglobin change.	After 3 and 6 months of intervention.	Glycated hemoglobin change assessed by difference in glycated hemoglobin concentration (%) comparing 3 and 6 months visits with respect to baseline.
Insulin change.	After 3 and 6 months of intervention.	Insulin change assessed by difference in fasting insulin concentration (UI/mL and %) comparing 3 and 6 months visits with respect to baseline.

Secondary

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

Other

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

Countries

Spain

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 5, 2026