Effect of a Low-carbohydrate Diet on Weight Loss in People Using the Injectable GLP-1 Agonist Semaglutide for Weight Loss

NCT07280403 | Completed

• 1 other identifier: INQ-2411
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to determine the effect of a low carbohydrate higher protein diet, modelled after the Atkins program on weight loss, glycemic control, risk markers of cardiovascular disease and body composition in patients taking semaglutide. Participants will:

• Be randomized to follow either a low carb, higher protein diet or a low fat diet for 3 months.
• Visit the clinic at week 2, 4, 8 and 12 to meet with a dietician, fill out a symptoms questionnaire and for bloodwork
• Complete 3-day food records 4 times over the 12 weeks.

Conditions

Weight Loss

Keywords

GLP-1 agonist; Semaglutide; Ozempic; Wegovy

Outcome Measures

Primary Outcomes (1)

• Body weight

  Percentage change from baseline of body weight

  12 weeks

Secondary Outcomes (7)

• BMI

  12 weeks

• Fat Mass

  12 weeks

• Fasting plasma glucose

  12 weeks

• Fat-free mass

  12 weeks

• Skeletal Muscle Mass

  12 weeks

Study Arms (2)

Low Carbohydrate

EXPERIMENTAL

Subjects randomized to the low-carbohydrate arm will be instructed on a reduced calorie diet (\<1400 kcal/day) consisting of an average macronutrient distribution of 20% carbohydrate, 30% protein and 50% fat with a maximum intake of 40g/day of available (net) carbohydrates (approximately 65-75g total carbohydrates). To complement the provided low carbohydrate shakes and snacks, dietary counselling will focus on choosing sources of protein and non-starchy vegetables

Behavioral: Low Carbohydrate

Low Fat

ACTIVE COMPARATOR

Subjects randomized to the low-fat arm will be instructed on a reduced calorie diet (\<1400 kcal/day) consisting of an average macronutrient distribution of 50% carbohydrate, 20% protein and 30% fat, with a maximum intake of 50g/day of fat. To complement the provided low fat shakes and snacks, dietary counselling will focus on choosing lean sources of protein and carbohydrates, while limiting high fat foods such as oils, nuts, full fat dairy, and fatty meats.

Behavioral: Low Fat

Interventions

Low Carbohydrate BEHAVIORAL

Low carbohydrate diet

Low Carbohydrate

Low Fat BEHAVIORAL

Low fat diet

Low Fat

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 18-75 years, inclusive
• Overweight or obese individuals with a BMI ≥26 kg/m²
• Non-pregnant, non-lactating individuals who are not planning on becoming pregnant during the trial and are using an effective method of contraception, as outlined: (a) Complete abstinence from intercourse two weeks prior to administration of the study product, and throughout the clinical trial. Participants utilizing this method must agree to use 2 alternate methods of contraception (see d) if they should become sexually active and will be queried on whether they have been abstinent at each study visit. b) Has a male sexual partner who is surgically sterilized prior to the Screening Visit and is the only male sexual partner for that Participant; c) Sexual partner(s) is/are exclusively female; d) Use of two acceptable methods of contraception, such as a spermicide, mechanical barrier (e.g. male condom, female diaphragm), tubal ligation, contraceptive pill, intrauterine device (IUD) or contraceptive implant. The Participant must be using these methods for at least 1 week prior to the screening visit and throughout their participation in the trial.
• Started semaglutide injections for weight loss 14 to 35 days prior to screening, inclusive, are tolerating it and are willing to continue taking it
• HbA1c ≤7.5%
• Not taking any hypoglycemic agent, apart from a semaglutide
• Systolic blood pressure \<160 mmHg and diastolic blood pressure \<100 mmHg
• Serum creatinine \<180 mmol/L (\<2.1 mg/dL)
• Serum triglycerides \<9 mmol/L (\<800 mg/dL)
• ALT or AST \<3 times the upper limit of normal
• Untreated LDL-cholesterol \<5.00 mmol/l (\<193 mg/dL)
• No major illness, trauma or surgery requiring hospitalization within 3mo of the screening visit
• Ability to understand the study procedures and willing to provide informed consent to participate in the study
• Subjects must be eligible to receive income in Canada and be covered by a health insurance plan such as OHIP
• Subjects are willing to sign the informed consent prior to any procedures conducted

You may not qualify if:

• High alcohol consumption (\>14 standard drinks per week or \>4 standard drinks per day for males; and \> 7 standard drinks per week or \>3 standard drinks per day for females), with 1 standard drink defined as containing approximately 14g of pure alcohol. Examples of 1 standard drink include: 12 oz of regular beer (approx. 5% alcohol), 5 oz of wine (approx. 12% alcohol) or 1.5 oz of distilled spirits (approx. 40% alcohol)
• Individuals with a history of bariatric surgery, gastrointestinal disease, any other medical conditions or use of supplements or medications that increase risk to the subject or others or may affect the results, as judged by the Principal Investigator
• Unwillingness or inability to comply with the experimental procedures and to follow INQUIS safety guidelines
• Known intolerance, sensitivity, or allergy to any ingredients in the study test products
• Subject is currently participating or recently (within 30 days of screening) participated in a clinical trial involving long-term exposure (greater than 24 hours) to an investigational drug, nutritional supplement, or lifestyle modification

Sponsors & Collaborators

• INQUIS Clinical Research: lead
• Simply Good Foods USA, Ltd.: collaborator

Study Sites (1)

INQUIS Clinical Research

Toronto, Ontario, M5C2N8, Canada

Location

MeSH Terms

Conditions

Weight Loss

Interventions

Diet, Fat-Restricted

Condition Hierarchy (Ancestors)

Body Weight Changes; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Diet Therapy; Nutrition Therapy; Therapeutics; Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Study Officials

• Janice Campbell

  INQUIS Clinical Research

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Randomized, open-label parallel design

Study Record Dates

• First Submitted: December 1, 2025
• First Posted: December 12, 2025
• Study Start: September 12, 2024
• Primary Completion: October 14, 2025
• Study Completion: November 30, 2025
• Last Updated: February 18, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

CA (1)