Egg Intake, Metabolic Outcomes and Choline Levels
- Conditions
- Obesity and Obesity-related Medical Conditions
- Registration Number
- NCT06687122
- Lead Sponsor
- University of Guelph
- Brief Summary
The purpose of this research is to determine the effect of additional daily egg intake on metabolic phenotypes and metabolism in the context of obesity.
- Detailed Description
Choline-derived phosphatidylcholine has diverse functions including being necessary for packaging and exporting triglycerides from the liver. Choline deficiency induces fatty liver, which occurs very commonly in overweight and obesity, emphasizing the importance of choline in lipid metabolism. Studies suggest the role of gut microbiota and host genetics in influencing choline availability, which gut microbes can convert choline to trimethylamine, and hepatically oxidized by flavin monooxygenase 3 to trimethylamine-N-oxide (TMAO), a recently emerged marker of disease. We have recently shown that phosphatidylcholine (the major form of choline in food) leads to higher plasma concentrations of choline without raising TMAO compared to no choline control, which metabolic heterogeneity in TMAO response that appears to be a function of individual gut microbiota composition. However, the effect of phosphatidylcholine on parameters of liver health and function in the context of obesity has not been examined. This study will leverage a whole-food approach using eggs, which are enriched in phosphatidylcholine, as a modulator of metabolic health with a focus on interindividual variation in response.
The study objectives are: 1) determine the effect of additional daily intake of eggs on metabolic outcomes (liver density and enzymes, circulating lipids and glucose levels, body mass index and adiposity); 2) assess the effects of additional daily intake of eggs on levels of choline and downstream metabolites including TMAO; 3) determine the relation between outcome variables in response to additional daily intake of eggs and metabolic modifiers including the gut microbiota composition and genetic polymorphism. To achieve these objectives, Phase I of the larger study will be conducted, which will have multiple "hits" to form the basis of targetable outcomes. Participants will be asked to keep their habitual diet during the 4-week baseline period, followed by 4 weeks of additional daily intake of 3 whole eggs (intervention) then 4 weeks without daily intake of eggs as a washout. Participants will be free-living and will not be supplied with any other food except for the eggs during the intervention period with no restrictions of energy intake. Participants will make clinic visits every 4 weeks for 12 weeks. At their first visit (week 0), before the intervention (week 4), after the intervention (week 8) and after the washout (week 12), participants will arrive overnight-fasted and liver imaging will be performed. Fasting blood will be obtained by a phlebotomist using a standard venipuncture procedure. Anthropometric measures including waist and hip circumferences and BMI will be collected. Participants will also be asked to turn in their fecal sample in a thermos-insulated bag with ice packs. All samples will be de-identified, distributed among storage vials and stored at -80°C until further analyses.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 20
- Male or female participant of any race or ethnicity between 30-65 (inclusive) years of age
- BMI > 30 kg/m2
- Non-smoker
- Willing to consume 3 eggs per day for one dietary period of 4 weeks
- Willing to avoid eggs during the rest of the study except for eggs that are provided
- Willing to follow the study protocol including maintaining usual lifestyle during the entire study
- Age < 30 or > 65 years
- BMI < 30 kg/m2
- Vegans or individuals who do not consume eggs
- Individuals who are currently pregnant or planning to become pregnant during the course of the study; or are currently breastfeeding
- Smokers, users of recreational drugs
- Individuals taking antibiotics or natural health products including prebiotics or probiotics
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Primary Outcome Measures
Name Time Method Liver physical density by imaging technologies Weeks 0, 4, 8 and 12 Liver morphology as assessed by imaging technologies Weeks 0, 4, 8 and 12 Concentration of circulating liver enzymes Weeks 0, 4, 8 and 12 Concentration of circulating lipid markers Weeks 0, 4, 8 and 12 Concentration of circulating glucose markers Weeks 0, 4, 8 and 12 Body mass index in kg/m^2 Weeks 0, 4, 8 and 12 Body circumference in metrics Weeks 0, 4, 8 and 12
- Secondary Outcome Measures
Name Time Method Choline metabolite response Weeks 0, 4, 8 and 12 Trimethylamine-N-oxide metabolite response Weeks 0, 4, 8 and 12 Flavin monooxygenase 3 (FMO3) 472 G>A genetic polymorphism Week 0 Composition of fecal microbiota Weeks 0, 4, 8 and 12
Trial Locations
- Locations (1)
Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec - ULaval
🇨🇦Quebec City, Quebec, Canada