Cardiovascular Disease
Conditions
Keywords
Strawberry Powder, Cardiovascular Disease Risk Factors
Brief summary
The purpose of this study is to evaluate the effects of freeze dried strawberry powder on LDL cholesterol, central and peripheral blood pressure, indices of arterial stiffness, and other lipid and lipoprotein concentrations. The investigators hypothesize that the bioactive compounds in freeze dried strawberry powder may elicit beneficial effects on LDL cholesterol, as well as blood pressure and arterial health.
Detailed description
The proposed study design is a 3-period randomized crossover dose-response study to evaluate the effect of freeze dried strawberry powder supplementation on LDL-C and vascular health. Research participants will be overweight or obese (BMI 25-39 kg/m\^2) but otherwise healthy adults with moderately elevated LDL-C (\>116 mg/dL or \>3.0mmol/L), blood pressure \<160/100 mmHg, total cholesterol below 273 mg/dL for men and below 284 mg/dL for women, and triglycerides below 350 mg/dL. Subjects will be randomly assigned to three supplementation periods: 1) low dose freeze dried strawberry powder (13 g/d); 2) high dose freeze dried strawberry powder (40 g/d); and 3) a placebo powder. Each powder will be provided for 4-6 weeks, separated by a 2-week washout period between treatment periods. Baseline and endpoint testing will include blood collection and vascular testing.
Interventions
DIETARY_SUPPLEMENTLow Dose Strawberry Powder
40 g composed of 13 g freeze dried strawberry powder + 27 g placebo powder
DIETARY_SUPPLEMENTHigh Dose Strawberry Powder
40 g freeze dried strawberry powder
DIETARY_SUPPLEMENTPlacebo Powder
40 g color and taste matched placebo powder
Sponsors
California Strawberry Commission
Penn State University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
35 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
1. Men and women 35-65 years of age 2. BMI ≥ 25 and ≤ 39 kg/m\^2 3. LDL-C \> 116 mg/dL 4. Total Cholesterol below 273 mg/dL for men and below 284 mg/dL for women 5. Triglycerides below 350 mg/d 6. Non-smokers 7. Blood pressure \< 160/100 mmHg
Exclusion criteria
1. History of acute or chronic inflammatory conditions or heart disease, kidney disease, liver disease, autoimmune disorders, or thyroid disease (unless controlled by medication and blood results within the previous 6 months are provided) 2. History of diabetes mellitus (and/or a fasting glucose \> 126 mg/dL at screening) 3. Stage II hypertension (blood pressure ≥ 160/100 mmHg) 4. Lactation, pregnancy, or desire to become pregnant during the study 5. Unwillingness to discontinue nutritional supplements, herbs, or vitamins, unless approved by investigator 6. Use of medications/supplements for elevated lipids, blood pressure, or glucose 7. Chronic use of non-steroidal anti-inflammatory or immunosuppressant medication 8. Conditions requiring the use of steroids 9. Unwillingness to refrain from blood donation prior to and during the study 10. Any medical condition or abnormal laboratory value that is judged clinically significant by an investigator 11. Allergy or sensitivity to strawberries or any ingredient in the study powders
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| LDL-C | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | LDL-C values calculated using the Friedewald equation |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Peripheral Blood Pressure | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Peripheral blood pressure measured using the SphygmoCor System |
| Augmentation Index | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Augmentation index measured using the SphygmoCor System |
| Pulse Wave Velocity | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Pulse wave velocity measured using the SphygmoCor System |
| High Sensitivity C Reactive Protein (hs-CRP) | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | hs-CRP will be measured by latex-enhanced immunonephelometry |
| Central Blood Pressure | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Aortic (central) blood pressure measured using the SphygmoCor System |
| Triglycerides | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Triglyceride values determined using enzymatic procedures |
| HDL-C | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | HDL-C will be estimated according to the modified heparin-manganese procedure |
| Oxidized LDL (oxLDL) | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Plasma concentrations of oxLDL will be measured using ELISA kits |
| Malondialdehyde (MDA) | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | MDA will be measured using the thiobarbituric acid reactive substances (TBARS) assay |
| Total Cholesterol | Change from baseline after 4 week treatments of low dose, high dose, and placebo strawberry beverage | Total cholesterol values determined by enzymatic procedures |
Countries
United States
Outcome results
None listed