Addition of Phytosterols to a Low Phytosterol Diet (phyteaux-I)

Regulation of Cholesterol Absorption: Dose Response of LDL to Phytosterols Added to a Phytosterol-Poor Diet

Studies have shown that phytosterols will lower LDL cholesterol. Typical diets can contain between 250 to 500 mg of naturally-occurring phytosterols. Long-term studies with phytosterol-containing products(such as margarines) have not taken into account the amounts of naturally occurring phytosterols in the diet. This means that the effects of small amounts of natural dietary phytosterols on LDL cholesterol are not known. In this study, we will examine the effects of phytosterols across a range of levels. The information will likely be used to further support and possibly extend the current dietary recommendations for phytosterol use.

Study Overview

• Status: Completed
• Conditions: Hypercholesterolemia; Coronary Heart Disease
• Intervention / Treatment: Dietary supplement: Different amount of phytosterols are added into diets

• Study Type: Interventional
• Enrollment (Actual): 18
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Louisiana
    • Baton Rouge, Louisiana, United States, 70808
      • Pennington Biomedical Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

Men and women are eligible who:

• are of any race or ethnicity between 18 to 80 years of age;
• are in generally good health;
• have moderately elevated blood cholesterol(LDL cholesterol between 100 and 189 mg/dl)
• will eat only the foods that are provided by the center during the diet periods;
• will drink no more than 5 cups of caffeine-containing beverages a day;
• will consume no more than 1 alcoholic drink a day;
• will abstain from the consumption of alcohol for 48-hours prior to blood draw days

Exclusion Criteria:

• are younger than 18 or older than 80 years;
• have very high cholesterol(LDL cholesterol equal to or above 190 mg/dl or triglycerides equal to or above 250 mg/dl);
• have very high blood pressure(equal to or above 160 mm Hg systolic or 95 mm Hg diastolic);
• are overweight( BMI greater than 35 kg/m2)
• are taking lipid-lowering, or any other medication known to affect blood cholesterol;
• have diabetes mellitus, cancer, heart, liver and/or kidney disease, or chronic disease that might interfere with participation;

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Medium Phytosterols; Diets with daily 400 mg of phytosterols	Dietary supplement: Different amount of phytosterols are added into diets; Diets with 59, 400, or 2000 mg of phytosterols daily for 4 weeks were given to each subject, in random order.
Experimental: High Phytosterols Diet; Diet with 2000 mg of daily phytosterols	Dietary supplement: Different amount of phytosterols are added into diets; Diets with 59, 400, or 2000 mg of phytosterols daily for 4 weeks were given to each subject, in random order.
Placebo Comparator: Low Phyto Diet; Diet with less than 100 mg of daily phytosterols	Dietary supplement: Different amount of phytosterols are added into diets; Diets with 59, 400, or 2000 mg of phytosterols daily for 4 weeks were given to each subject, in random order.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Fecal cholesterol excretion	At the end of week 4 on each diet

Secondary Outcome Measures

Outcome Measure	Time Frame
intestinal cholesterol absorption	At the end of week 4 on each diet

Collaborators and Investigators

• Sponsor: Washington University School of Medicine
• Collaborators: Pennington Biomedical Research Center
• Investigators: Principal Investigator: Richard Ostlund, MD, Washington University School of Medicine

Publications and helpful links

General Publications

• Racette SB, Lin X, Lefevre M, Spearie CA, Most MM, Ma L, Ostlund RE Jr. Dose effects of dietary phytosterols on cholesterol metabolism: a controlled feeding study. Am J Clin Nutr. 2010 Jan;91(1):32-8. doi: 10.3945/ajcn.2009.28070. Epub 2009 Nov 4.

Study record dates

Study Major Dates

• Study Start: March 1, 2006
• Primary Completion (Actual): September 1, 2006
• Study Completion (Actual): October 1, 2008

Study Registration Dates

• First Submitted: March 10, 2009
• First Submitted That Met QC Criteria: March 10, 2009
• First Posted (Estimate): March 11, 2009

Study Record Updates

• Last Update Posted (Estimate): April 19, 2012
• Last Update Submitted That Met QC Criteria: April 17, 2012
• Last Verified: April 1, 2012

More Information

Terms related to this study

• Keywords: diet; mass spectrometry; cholesterol absorption; phytosterols; cholesterol excretion; deuterium
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Metabolic Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Lipid Metabolism Disorders; Hyperlipidemias; Dyslipidemias; Heart Diseases; Coronary Artery Disease; Myocardial Ischemia; Coronary Disease; Hypercholesterolemia
• Other Study ID Numbers: PBRC25025; R01HL050420 (U.S. NIH Grant/Contract)