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Active, Not Recruiting

NCT Number: NCT04234373

Effect of a Low-carb Dietary Intervention in Obese Patients: a Pilot Trial

Effects of a 6 months low-carb dietary intervention on glycemic control, body composition and gut-brain interaction in obese and lean patients with and without glucose intolerance or diabetes

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

Glucose Intolerance Body Weight Glucose Metabolism Disorders Hyperglycemia Metabolic Diseases Nutrition Disorders Nutritional and Metabolic Diseases Obesity Overnutrition Overweight Pathological Conditions, Signs and Symptoms Signs and Symptoms

Age range

18 year–55 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

St Clara Research Ltd, St Claraspital Basel

Basel, 4002, Switzerland

Who can participate

Healthy volunteers accepted: Yes

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

Inclusion criteria

Group A: HEALTHY LEAN CONTROLS

  • Healthy normal weight subjects with a body-mass index of 19.0-24.9kg/m2, HbA1C <5.7% and fasting glucose <5.6 mmol/l
  • Normal eating habits
  • Stable body weight for at least three months
  • Informed Consent as documented by signature

Group B: PRE-DIABETIC or DIABETIC OBESE

  • Pre-diabetic/Diabetic obese with a HbA1C >5.7% and/or fasting glucose >5.6 mmol/l) and body-mass index > 30kg/m2, otherwise healthy
  • Normal eating habits
  • Stable body weight for at least three months
  • Informed Consent as documented by signature

Exclusion criteria

Group A: HEALTHY LEAN CONTROLS

  • Pre-existing low carb diet (less than 45% of daily energy intake by carbohydrates)
  • Pre-existing diet (vegetarian, vegan, gluten-free etc.)
  • Psychiatric illness
  • Alcohol abuse, (smoking allowed)
  • Regular intake of medications, (oral contraceptives allowed)
  • Intake of antibiotics within the last 3 months before inclusion
  • Regular intake of pro- or prebiotics
  • Chronic diseases of the gastrointestinal tract, history of gastrointestinal surgery with major changes to the gastrointestinal tract (e.g. bariatric surgery)
  • Clinically relevant acute or chronic inflammatory disease
  • Pregnancy
  • Participation in another study with investigational drug within the 30 days preceding and during the present study.

Group B: PRE-DIABETIC or DIABETIC OBESE

  • Pre-existing low carb diet (less than 45% of daily energy intake by carbohydrates)
  • Pre-existing diet (vegetarian, vegan, gluten-free etc.)
  • Psychiatric illness
  • Alcohol abuse, (smoking allowed)
  • Regular intake of medications (except: oral contraceptives, metformin, SGLT-2, statins, and antihypertensive, which are allowed)
  • Intake of antibiotics within the last 3 months before inclusion
  • Regular intake of pro- or prebiotics
  • Chronic diseases of the gastrointestinal tract, history of gastrointestinal surgery with major changes to the gastrointestinal tract (e.g. bariatric surgery)
  • Clinically relevant acute or chronic inflammatory disease
  • Pregnancy
  • Participation in another study with investigational drug within the 30 days preceding and during the present study.

Treatment and study plan

Low Carb Diet

Other

Low Carb diet (max. 130g carbohydrates/d) for 6 months

Primary outcomes

  1. Effect of a low-carb dietary intervention on glycemic control as defined by blood glucose level at 2h after an oral glucose tolerance test.

    Time frame: Change from baseline to 6 months

Secondary outcomes

  1. Effect of a low-carb dietary intervention on body composition as measured with dual-energy x-ray absorptiometry

    Time frame: Change from baseline to 6 months

  2. Effect of a low-carb dietary intervention on metabolomics as measured in plasma, urine and stool samples

    Time frame: Change from baseline to 6 months

    Metabolomic analysis of the bacterial metabolites present in the urine by combining nuclear magnetic resonance (1H-NMR) and mass spectrometry

  3. Effect of a low-carb dietary intervention on gut microbiota composition as measured in stool samples

    Time frame: Change from baseline to 6 months

    Human gut microbiota composition measured with metagenomic shotgun sequencing

  4. Effect of a low-carb dietary Intervention on brain network activity as measured with functional MRI

    Time frame: Change from baseline to 6 months

  5. Effect of a low-carb dietary intervention on liver fat fraction as measured with MRI

    Time frame: Change from baseline to 6 months

Sponsors and collaborators

Lead sponsor

University Hospital, Basel, Switzerland

Other

Registry information

Official study title

Understanding Gut-brain Interactions and the Effect of a Low-carb Dietary Intervention in Obese Patients With and Without Glucose Intolerance or Diabetes: a Pilot Trial

Important dates

Study start
2020
Primary completion
2026
Study completion
2026
First posted
Jan 21, 2020
Registry last updated
May 4, 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.

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