Cardiovascular Diseases, Hypercholesterolemia, Hyperlipidemia
Conditions
Keywords
Viscous dietary fiber, Soy protein, Nuts, Plant sterols, Dietary Portfolio, Compliance, Blood lipids, Blood pressure
Brief summary
The purpose of this study is to evaluate the long term effectiveness of the dietary portfolio, consisting of viscous fibers, soy products, nuts and plant sterols, as well as the effects of removing single food components from the dietary portfolio on cholesterol reduction and other cardiovascular risk factors.
Detailed description
We have shown in 1-month metabolic studies that a dietary portfolio, consisting of soy products, viscous fibers, almonds and plant sterols in the form of margarine, can lower cholesterol to the same extent as first generation statins (cholesterol-lowering drugs). However, the long-term effectiveness of the dietary portfolio is not known. Furthermore, it is not known to what extent each of the food components contribute to the cholesterol reductions observed. We wish to therefore evaluate the long term effects of the dietary portfolio as well as the effects of removing single food components from the dietary portfolio on cholesterol reduction and other cardiovascular risk factors. We believe the removal of single food components will result in a reduction of the cholesterol-lowering effect to a similar extent as predicted with the cholesterol reductions observed when the food component is consumed alone. Method: 66 subjects will be recruited for a 6-month to 5 year long-term dietary portfolio study with the option for continuation (re-consenting) at the end of 6, 12 or 24 months. The active dietary components consist of viscous fibers (including oat bran), soy products (including soy milk), almonds and plant sterols (sterol-enriched margarine). Lipids, blood pressure, body weight, and routine biochemical and hematology analyses will be performed over the 5 year period, with lipids and blood pressure measured at 2 monthly intervals. 40-50 subjects on the long term dietary portfolio study, all of whom will have been on the diet for at least 1 year, will be asked to remove a specific food component from their regular dietary portfolio for a 10 week period. After the 10 week period, subjects will be asked return to the normal dietary portfolio with all food components consumed and continue on the long-term dietary portfolio. Bloods will be taken at weeks 0, 6 and 10 of the food component removal period; and at 2-monthly intervals for 20 weeks prior to and after the 10 week period while on the long-term dietary portfolio with all food components.
Interventions
DIETARY_SUPPLEMENTDietary portfolio of cholesterol-lowering foods
A plant based dietary portfolio providing plant sterols (1.0g/1000 kcal), soy protein (22.5g/1000 kcal, viscous fibers 10 g/1000 kcal and almonds 22.5g/1000 kcal)
Sponsors
Canada Research Chairs Endowment of the Federal Government of Canada
Natural Sciences and Engineering Research Council, Canada
Loblaw Companies Limited
Almond Board of California
Unilever R&D
University of Toronto
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
21 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Healthy adult men and postmenopausal women currently enrolled in the long-term portfolio study * Body mass index \<32 kg/m2 * Constant body weight over last 6 months preceding the onset of the study * Fasting LDL-cholesterol concentration \>4.1 mmol/L at diagnosis
Exclusion criteria
* women of child-bearing potential * major cardiovascular event (stroke or myocardial infarction) * positive molecular diagnosis of familial hypercholesterolemia * secondary causes of hypercholesterolemia (hypothyroidism, unless treated & on a stable dose of L-thyroxine, renal or liver disease) * use of cholesterol-lowering medications * serum triglycerides \>4.5 mmol/L * blood pressure \> 145/90 mmHg * diabetes and/or major disorders such as liver disease, renal failure or cancer * major surgery \<6 months prior to randomization * alcohol consumption \>2 drinks per day
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Total cholesterol | At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years |
| LDL cholesterol | At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years |
| C-reactive protein | At weeks 0, 12, 24, 34, 52; then every 6 months to a total of 5 years |
| Blood pressure | At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years |
Secondary
| Measure | Time frame |
|---|---|
| Compliance to dietary portfolio components | At years, 1, 2, 3, 4 and 5 |
| Body Weight | At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years |
| Oxidative stress markers | week 0 and every 6 months to 5 years |
| 24 hour urinary markers and electrolytes (optional) | At week 0 and end of years 1, 2, 3, 4 and 5 |
| Apolipoprotein A1 and B | At weeks 0, 2,4, 8,12, 18, 24, 34, 44, 52; then every 2 months to a total of 5 years |
| Lp(a) | At weeks 0, 24, 52; then every 6 months to a total of 5 years |
| Routine Biochemistry and hematology measurements | At week 0, 12, 24 and every 6 months to 5 years |
Countries
Canada
Outcome results
None listed