NCT06668168

Brief Summary

Excess weight increases the risk of several diseases including cardiovascular disease, type 2 diabetes, kidney disease and various cancers. There is a need for preventative strategies for obesity-associated disease, especially for people in the overweight and moderately obese ranges where pharmacological intervention may not be suitable. Low-carbohydrate (ketogenic) diets are popular for weight control. Ketogenic diets increase circulating ketones, which can have favourable effects on cardiometabolic health markers. However, the ketogenic diet has a nutrient composition associated with harms (high-saturated fat/red meat, and low-fibre). The net effects of ketogenic diets on long-term health are unclear. Ketone supplements can increase circulating ketones and could provide benefits of ketosis without needing to adhere to a potentially harmful diet. Establishing causality between complex exposures (e.g., diet) and long-term outcomes (e.g., disease), is challenging. The MRC \& NIHR Review of Nutrition and Human Health Research (2017) highlighted an "overreliance (as opposed to reasonable reliance) on observational studies" as a key barrier to progression in the field of nutrition and health. Randomised controlled trials (RCTs) facilitate causal inference, but for long-term outcomes are expensive, time-consuming, and often suffer from waning adherence. Mendelian randomization (MR) can estimate causal effects subject to key assumptions. A challenge to these assumptions includes complex behavioural exposures (e.g., diet), which could be intercorrelated with causal factors. Our proposal will address these limitations with a novel combination of study designs to establish causal effects of ketosis (via diet and supplementation) on obesity-associated disease risk in humans. The investigators will combine a tightly controlled, short-term RCT, with MR to link short-term responses to long-term endpoints. The investigators will examine the circulating (blood) and tissue-specific (adipose) transcriptomic and proteomic responses in the fasted and postprandial state in response to our dietary interventions and translate these to MR by identifying single-nucleotide polymorphisms from genome wide association studies. This approach overcomes limitations of RCTs and MR, as adherence to diets will be confirmed with controlled feeding, and intermediate molecular traits as exposure for MR are less likely to be intercorrelated with causal traits.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
69

participants targeted

Target at P50-P75 for not_applicable

Timeline
45mo left

Started May 2025

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress22%
May 2025Jan 2030

First Submitted

Initial submission to the registry

October 30, 2024

Completed
1 day until next milestone

First Posted

Study publicly available on registry

October 31, 2024

Completed
6 months until next milestone

Study Start

First participant enrolled

May 6, 2025

Completed
2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 6, 2027

Expected
2.7 years until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2030

Last Updated

July 31, 2025

Status Verified

July 1, 2025

Enrollment Period

2 years

First QC Date

October 30, 2024

Last Update Submit

July 28, 2025

Conditions

Keywords

Ketogenic diet

Outcome Measures

Primary Outcomes (3)

  • Plasma proteome

    Plasma proteome at week 4 adjusted for baseline values

    From baseline to week 4

  • Transcriptome of peripheral blood mononuclear cells

    Transcriptome of peripheral blood mononuclear cells at week 4 adjusting for baseline values

    From baseline to week 4

  • Transcriptome of adipose tissue

    Transcriptome of subcutaneous abdominal adipose tissue at week 4 adjusting for baseline values

    From baseline to week 4

Secondary Outcomes (3)

  • Apolipoprotein B concentrations

    From baseline to week 4

  • Urinary albumin concentrations

    From baseline to week 4

  • Fasting glucose concentrations

    From baseline to week 4

Study Arms (3)

CONTROL

NO INTERVENTION

KETONE ESTER

ACTIVE COMPARATOR
Dietary Supplement: Ketone Monoester (KE)

KETOGENIC DIET

EXPERIMENTAL
Behavioral: Ketogenic diet

Interventions

Ketone Monoester (KE)DIETARY_SUPPLEMENT

25g ketone ester 3x/day. The ketone ester will be a beta-hydroxybutyrate monoester \[(R)-3-hydroxybutyl (R)-3-hydroxybutyrate\].

KETONE ESTER
Ketogenic dietBEHAVIORAL

Ketogenic diet (\<50 g carbohydrate per day)

KETOGENIC DIET

Eligibility Criteria

Age18 Years - 65 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Body mass index: 25-45 kg/m2
  • Waist circumference \>93.9 (males) or \>79.9 (females)

You may not qualify if:

  • Glucose or lipid lowering medication
  • Diagnosis of cardiovascular disease, renal failure, liver disease or type 2 diabetes
  • Contraindications to a ketogenic diet (e.g., pancreatitis, liver failure, disorders of fat metabolism, primary carnitine deficiency, carnitine palmitoyltransferase deficiency, carnitine translocase deficiency, porphyrias, or pyruvate kinase deficiency)
  • Unable to understand English language

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of Bath

Bath, Bath, BA2 7AY, United Kingdom

RECRUITING

MeSH Terms

Conditions

ObesityOverweight

Interventions

Diet, Ketogenic

Condition Hierarchy (Ancestors)

OvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Diet, Carbohydrate-RestrictedDiet TherapyNutrition TherapyTherapeuticsDietNutritional Physiological PhenomenaDiet, Food, and NutritionPhysiological Phenomena

Central Study Contacts

Sophie L Russell, PhD

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Masking Details
Outcome assessors will be masked to the group allocation when analysis is outsourced from the University.
Purpose
BASIC SCIENCE
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor of Nutrition and Metabolism

Study Record Dates

First Submitted

October 30, 2024

First Posted

October 31, 2024

Study Start

May 6, 2025

Primary Completion (Estimated)

May 6, 2027

Study Completion (Estimated)

January 1, 2030

Last Updated

July 31, 2025

Record last verified: 2025-07

Locations