Clinical trial NCT00860509: Comparison of Low and High Phytosterol Diets With Respect to Cholesterol Metabolism
Official title: Phyteaux-II- Regulation of Cholesterol Absorption: Response of LDL to Low and Naturally High Phytosterol Diets
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Hypercholesterolemia
Coronary Heart Disease
Keywords: phytosterols
cholesterol excretion
cholesterol absorption
diet
mass spectrometry
deuterium
Lead sponsor: Washington University School of Medicine
Sponsor class: OTHER
Collaborators: name: Pennington Biomedical Research Center
First posted: 2009-03-12
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: The objective of this study is to compare cholesterol absorption and metabolism after feeding diets naturally low or high in phytosterols. All meals will be prepared in a metabolic kitchen and analyzed for phytosterols. In a randomized crossover design a group of up to 25 healthy subjects will consume diets containing either 100 mg/day or 600 mg/day phytosterols for 4 weeks. At the end of each dietary period percent cholesterol absorption, fecal cholesterol excretion and LDL cholesterol level will be measured. The hypothesis is that LDL cholesterol and cholesterol excretion will be improved on the high phytosterol diet even though macronutrient composition, mineral intake and fiber consumption are similar.


Eligibility criteria: Inclusion Criteria:

* Male or female of any race or ethnicity between 18 to 80 years of age, inclusive;
* Body mass index between 20-35 kg/m2;
* LDL-cholesterol between 100-189 mg/dL based on the average of duplicate screening measures. If the two LDL-C levels differ by more than 30 mg/dL, a third test will be scheduled with all three results averaged;
* Free of chronic disease;
* Willing to eat only the foods that are provided by the Center during the diet periods;
* Willing to consume no more than 1 alcoholic drink per day.
* Willing to abstain from the consumption of alcohol for 48-hours prior to blood draw days;
* Willing to drink no more than 5 cups of caffeine-containing beverages a day.

Exclusion Criteria:

* Age \< 18 or \> 80 years;
* Based on duplicate screening laboratory values: 1) LDL-C \> or = 190 mg/dL; 2) TG \> or = 250 mg/dL; 3) blood pressure \> or = 160 mm Hg systolic or 95 mm Hg diastolic;
* Documented presence of atherosclerotic disease;
* Diabetes mellitus;
* Renal, hepatic, endocrine, gastrointestinal, hematological or other systemic disease;
* Body mass index \> 35;
* For women, pregnancy, breast feeding or postpartum \< 6 months;
* For women, peri-menopausal;
* History of drug or alcohol abuse;
* History of depression or mental illness requiring treatment or medication within the last 6 months;
* Multiple food allergies or significant food preferences or restrictions that would interfere with diet adherence;
* Chronic use of over-the-counter medication which would interfere with study endpoints including laxatives and antacids;
* Lifestyle or schedule incompatible with the study protocol;
* Planned continued use of dietary supplements through the study trial;
* Taking any lipid-lowering, or other medications known to affect blood cholesterol

Primary outcomes:
measure: Fecal cholesterol excretion
timeFrame: At the end of week 4 on each diet
Secondary outcomes:
measure: Intestinal cholesterol absorption
timeFrame: At the end of week 4 on each diet
Other outcomes:
Locations:
city: Baton Rouge
country: United States
facility: Pennington Biomedical Research Center-Louisana State University System
state: Louisiana
Study officials:
affiliation: Washington University School of Medicine
name: Richard Ostlund, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lin X, Racette SB, Lefevre M, Spearie CA, Most M, Ma L, Ostlund RE Jr. The effects of phytosterols present in natural food matrices on cholesterol metabolism and LDL-cholesterol: a controlled feeding trial. Eur J Clin Nutr. 2010 Dec;64(12):1481-7. doi: 10.1038/ejcn.2010.180. Epub 2010 Sep 1.