Skip to main content
OpenTrials
Completed

NCT Number: NCT07830121

Very-Low-Carbohydrate Diet for Prediabetes and Obesity

Prediabetes is a condition where blood sugar is higher than normal but not yet high enough to be called type 2 diabetes. It is common in adults who are overweight or obese, and without treatment it often progresses to diabetes over time.

This study looks at whether following a very-low-carbohydrate diet for 12 weeks can help adults with prediabetes and obesity lose weight, reduce body fat, and improve how well their body responds to insulin, compared with standard dietary advice.

Adults aged 30 to 65 with obesity and newly diagnosed prediabetes are invited to take part. Participants are randomly assigned to one of two groups: one follows a very-low-carbohydrate diet with support from a dietitian, and the other receives standard dietary advice without a specific carbohydrate limit. Both groups are followed for 12 weeks, during which their weight, body composition, blood sugar, insulin levels, cholesterol, and kidney function are checked.

The study aims to find out whether the very-low-carbohydrate diet leads to greater improvements in weight, body fat, and insulin sensitivity than standard advice, and whether it is safe and practical to follow in everyday life. The findings may help doctors and dietitians offer more effective ways to prevent prediabetes from progressing to type 2 diabetes.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

PreDiabetes Body Weight Body Weight Changes Diabetes Mellitus Endocrine System Diseases Glucose Metabolism Disorders Hyperinsulinism Insulin Resistance Metabolic Diseases Nutrition Disorders Nutritional and Metabolic Diseases Obesity Obesity / Overweight Overnutrition Overweight Pathological Conditions, Signs and Symptoms Prediabetic State Signs and Symptoms VERY LOW CARBOHYDRATE DIET Weight Loss

Age range

30 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Hospital UITM

Sungai Buloh, Selangor, 47000, Malaysia

About this study

Obesity and prediabetes frequently coexist and share a common pathophysiological pathway: excess visceral adiposity promotes chronic low-grade inflammation and insulin resistance, accelerating progression from normoglycaemia to prediabetes and ultimately to type 2 diabetes mellitus (T2DM). While carbohydrate-restricted dietary interventions have demonstrated efficacy for weight loss and glycaemic improvement in patients with established T2DM and diabetic kidney disease, their effects have not been well characterised in the earlier, potentially reversible stage of prediabetes, where intervention may carry the greatest preventive value.

This single-centre, randomized controlled trial evaluates the effects of a 12-week very-low-carbohydrate diet (VLCBD, less than 50 g carbohydrate/day) compared with standard dietary advice (no specific carbohydrate restriction) in adults with obesity and prediabetes attending a tertiary endocrine outpatient clinic in Malaysia. Both study arms receive individualised caloric intake based on ideal body weight, structured dietary counselling, and food diaries for adherence monitoring.

The study compares the two dietary approaches with respect to anthropometric and body composition changes, insulin resistance, and the safety and feasibility of the VLCBD approach over the 12-week intervention period, with assessments at baseline and at Week 12. Findings are intended to inform whether carbohydrate restriction is a feasible, safe, and effective dietary strategy for reducing cardiometabolic risk and preventing progression to type 2 diabetes in adults with prediabetes and obesity - a population not directly addressed by prior low-carbohydrate diet trials, which have been conducted mainly in patients with established diabetes.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age 30 to 65 years
  • Body mass index (BMI) 23-40 kg/m²
  • Diagnosis of prediabetes, defined as fasting blood glucose (FBG) 5.6-6.9 mmol/L or glycated haemoglobin (HbA1c) 5.6-6.2%
  • Able to stand independently
  • Able to provide written informed consent

Exclusion criteria

  • Diagnosis of type 1 or type 2 diabetes mellitus
  • Calculated creatinine clearance <60 mL/min/1.73 m²
  • on antiobesity medications
  • On medications that can interfere with glucose metabolism
  • Heart failure, New York Heart Association (NYHA) functional class III-IV
  • Active systemic inflammatory disease
  • Chronic kidney disease requiring haemodialysis
  • Active hepatic disease
  • Collagen vascular disease
  • Malignancy
  • Acute coronary syndrome within the preceding 3 months
  • Pregnancy or breastfeeding
  • Plans to conceive within the following year

Treatment and study plan

Standard Dietary Advice

Behavioral

Participants received standard dietary advice with no specific carbohydrate restriction, with total caloric intake individualised to ideal body weight, the same dietitian counselling, and food diaries, for 12 weeks.

Very-Low-Carbohydrate Diet (VLCBD)

Behavioral

Participants received a very-low-carbohydrate diet (<50 g carbohydrate/day), with total caloric intake individualised to ideal body weight, structured dietitian counselling, and food diaries, for 12 weeks.

Primary outcomes

  1. Change From Baseline in Body Weight at Week 12

    Time frame: Baseline and Week 12

    Body weight was measured in kilograms (kg) using a calibrated digital scale, with participants in light clothing and without shoes.

  2. Change From Baseline in Body Mass Index (BMI) at Week 12

    Time frame: Baseline and Week 12

    BMI was calculated as weight in kilograms divided by height in meters squared (kg/m²).

  3. Change From Baseline in Waist Circumference at Week 12

    Time frame: Baseline and Week 12

    Waist circumference was measured in centimetres (cm) at the midpoint between the lowest rib and the iliac crest.

  4. Change From Baseline in Body Fat Percentage at Week 12

    Time frame: Baseline and Week 12

    Body fat percentage was measured using bioelectrical impedance analysis expressed as a percentage of total body weight.

Secondary outcomes

  1. Change in HOMA-IR

    Time frame: Baseline and week 12

    Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), calculated as fasting insulin (mU/L) × fasting glucose (mmol/L) ÷ 22.5, was compared between arms from baseline to Week 12 to assess insulin resistance.

  2. Change From Baseline in Estimated Glomerular Filtration Rate (eGFR) at Week 12

    Time frame: Baseline and Week 12

    eGFR was calculated from serum creatinine using the CKD-EPI formula, expressed in mL/min/1.73m²

  3. Participant Retention Rate at Week 12

    Time frame: Baseline and Week 12

    Retention rate was defined as the number of participants completing the Week 12 assessment divided by the number randomized, expressed as a percentage

Sponsors and collaborators

Lead sponsor

Universiti Teknologi Mara

Other

Registry information

Official study title

Effects of a 12-Week Very-Low-Carbohydrate Diet on Body Composition and Cardiometabolic Outcomes in Adults With Prediabetes and Obesity: A Randomised Controlled Trial

Acronym: VLCBD

Important dates

Study start
2024
Primary completion
2025
Study completion
2025
First posted
Sep 21, 2026
Registry last updated
Sep 21, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.