Independent Effects of High-cholesterol (High-egg) and High-saturated Fat Diets on LDL-cholesterol

NCT05267522 | Completed

• 1 other identifier: 204327
• Study Type: interventional
• Target: 77
• Locations: 1 country
• Sites: 1

Brief Summary

This study will comprise a randomized controlled, counter-balanced, cross-over trial to evaluate the independent effects of a high cholesterol (high egg), low saturated fat diet and a high saturated fat, low cholesterol diet on blood lipids. Evaluations also include analysis of physical activity as there is emerging evidence that the lutein and zeaxanthin in egg yolk may increase physical activity levels by crossing the blood-brain barrier and altering neuronal function. The study will also investigate effects on a number of novel lipoprotein parameters (particle size and particle concentrations).

Conditions

Hypercholesterolemia; Hyperlipidemias; Physical Inactivity; Diet, Healthy

Keywords

Cholesterol; Eggs; Saturated Fat; Low density lipoprotein cholesterol; lutein; physical activity

Outcome Measures

Primary Outcomes (4)

• Low-density lipoprotein cholesterol (LDL-C)

  Plasma LDL-C levels (mmol/L)

  Baseline

• Low-density lipoprotein cholesterol (LDL-C)

  Plasma LDL-C levels (mmol/L)

  5 weeks

• Low-density lipoprotein cholesterol (LDL-C)

  Plasma LDL-C levels (mmol/L)

  10 weeks

• Low-density lipoprotein cholesterol (LDL-C)

  Plasma LDL-C levels (mmol/L)

  15 weeks

Secondary Outcomes (44)

• Blood lipid profiling

  Baseline

• Blood lipid profiling

  5 weeks

• Blood lipid profiling

  10 weeks

• Blood lipid profiling

  15 weeks

• Fasting glucose

  Baseline

Study Arms (3)

Egg Diet

EXPERIMENTAL

Egg diet, contains 2 eggs per day and limits saturated fat to 6% of energy intake. Cholesterol intake is 600mg/day. Protein and carbohydrate levels will be maintained at 20% and 40% of energy intake, respectively. This diet will be followed for 5 weeks.

Other: Egg diet

Egg-free Diet

ACTIVE COMPARATOR

Egg-free diet, limits cholesterol to 300 mg/day (no eggs) with saturated fat intake at 12% of energy intake. Protein and carbohydrate levels will be maintained at 25% and 40% of energy intake, respectively. This diet will be followed for 5 weeks.

Other: Egg-free Diet

Control Diet

ACTIVE COMPARATOR

Comparator diet based on the average Australian diet, limited to 1 egg per week, with saturated fat intake at 12% of energy intake. Cholesterol intake is 600 mg/day. Protein and carbohydrate levels will be maintained at 25% and 40% of energy intake, respectively. This diet will be followed for 5 weeks.

Other: Control Diet

Interventions

Egg diet OTHER

30% fat \[6% saturated fat\], 20% protein, 40% carbohydrate, 600 mg cholesterol

Also known as: High cholesterol + low saturated fat diet

Egg Diet

Egg-free Diet OTHER

30% fat \[12% saturated fat\], 25% protein, 40% carbohydrate, 300 mg cholesterol

Also known as: Low cholesterol + high saturated fat diet

Egg-free Diet

Control Diet OTHER

30% fat \[12% saturated fat\], 25% protein, 40% carbohydrate, 600 mg cholesterol

Also known as: Average Australian Diet

Control Diet

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Male or female, aged 18 - 60 years
• Blood LDL-C \<3.5 mmol/L (measured at screening using an automated analyser (Cholestech LDX System).
• Non-smoker (or other nicotine products) (minimum 6 months).

You may not qualify if:

• Have diagnosed cardiovascular disease (including uncontrolled high blood pressure) or a chronic disease, including Type-1 or -2 diabetes, kidney or liver disease, gastrointestinal disorders requiring medical nutrition therapy (e.g., Crohn's disease, irritable bowel, coeliac disease) or any other condition that may have an impact on study outcomes.
• Have allergies or strong aversion to eggs or other components of the test foods (diets are not suitable for vegetarians).
• Consume more than 5 eggs per week in the month prior to beginning the trial.
• Participant has a recent history (within 12 months) or strong potential for alcohol abuse. Defined as \>14 standard drinks per week.
• Have changed medication or supplementation that might affect study outcomes in the last 3 months.
• Take vitamin, mineral, herbal supplementation, or medications that may have an impact on study outcomes.
• Are already involved in another research project within 30 days of commencement of the present study that in the opinion of the investigators will be unsuitable for this study.
• Are pregnant or breastfeeding.
• Show unwillingness to be randomized to either experimental group.
• Failure to satisfy the investigator regarding suitability to participate for any other reason.
• Are unwilling or unable to provide written informed consent.

Sponsors & Collaborators

• University of South Australia: lead
• American Egg Board: collaborator

Study Sites (1)

University of South Australia Clinical Trial Facility

Adelaide, South Australia, 5000, Australia

Location

Related Publications (2)

• Carter S, Hill AM, Yandell C, Wood L, Coates AM, Buckley JD. Impact of dietary cholesterol from eggs and saturated fat on LDL cholesterol levels: a randomized cross-over study. Am J Clin Nutr. 2025 Jul;122(1):83-91. doi: 10.1016/j.ajcnut.2025.05.001. Epub 2025 May 6.

  PMID: 40339906 DERIVED

• Carter S, Hill AM, Yandell C, Buckley JD, Coates AM. Study protocol for a 15-week randomised controlled trial assessing the independent effects of high-cholesterol and high-saturated fat diets on LDL cholesterol. BMJ Open. 2024 Jan 25;14(1):e081664. doi: 10.1136/bmjopen-2023-081664.

  PMID: 38272555 DERIVED

MeSH Terms

Conditions

Hypercholesterolemia; Hyperlipidemias; Sedentary Behavior; Motor Activity

Condition Hierarchy (Ancestors)

Dyslipidemias; Lipid Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Behavior

Study Officials

• Jonathan D Buckley, PhD

  University of South Australia

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: It will not be possible to blind participants to the diet being consumed, or the research dietician assisting the participants to comply with the diets. All other research staff involved in data collection will be blinded.
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dean of Programs (Human Performance)

Model Details: Counter-balanced, cross-over trial with randomization to the starting diet will be via minimization, based on the LDL-C concentration at screening and sex. Minimization will ensure balanced LDL-C and sex between the treatment groups at commencement of each of the three diets.

Study Record Dates

• First Submitted: February 2, 2022
• First Posted: March 4, 2022
• Study Start: March 1, 2022
• Primary Completion: August 10, 2023
• Study Completion: August 31, 2023
• Last Updated: December 13, 2023

Record last verified: 2022-03

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1)