Effects of Purple Vegetables on Cardiovascular Disease (CVD) Risk Factors

Sponsor

University of Guelph (Other)

Overall Status

Unknown status

CT.gov ID

NCT01564498

Collaborator

Ontario Ministry of Agriculture, Food and Rural Affairs (Other)

Enrollment

Location

Arms

Duration (Months)

0.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The hypothesis is that richly coloured purple vegetables, rich in polyphenolic compounds including anthocyanins will have higher antioxidant and other biological activities, than more lightly coloured versions of these foods. Diets of human subjects will be modified to allow consumption of 200-300 g of raw carrots or cooked potatoes. Participants will be randomized to consume either orange or purple carrots, or white or purple potatoes. They will consume these diets for 12 weeks and bioavailability of polyphenolics will be examined as well as anthropometry and blood biochemistry for changes in risk factors associated with cardiovascular disease.

Condition or Disease	Intervention/Treatment	Phase
Hypertension Hypercholesterolemia Type II Diabetes Obesity Inflammation	Other: vegetable	Phase 1

Study Design

Study Type:

Interventional

Anticipated Enrollment :

60 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

None (Open Label)

Primary Purpose:

Prevention

Official Title:

A Pilot Study of the Effects of Replacing Orange Carrots and White Potatoes With Purple Varieties, on Risk Factors for Cardiovascular Disease

Study Start Date :

Apr 1, 2012

Anticipated Primary Completion Date :

Dec 1, 2017

Anticipated Study Completion Date :

Dec 1, 2017

Arms and Interventions

Arm	Intervention/Treatment
Placebo Comparator: White potato Participants will consume 300-500 g of cooked white potatoes per day	Other: vegetable 200-300 g raw carrots or 300-500 g cooked potatoes
Experimental: Purple Potato Participants will consume 300-500 g of cooked purple potato per day	Other: vegetable 200-300 g raw carrots or 300-500 g cooked potatoes
Placebo Comparator: Orange carrots Participants will consume 200-300 g typical varieties of orange carrots during the intervention	Other: vegetable 200-300 g raw carrots or 300-500 g cooked potatoes
Experimental: Purple Carrots Participants will consume 200-300 g raw purple carrots instead of orange carrots in the control arm	Other: vegetable 200-300 g raw carrots or 300-500 g cooked potatoes

Outcome Measures

Primary Outcome Measures

Blood cholesterol [12 weeks]
blood will be collected at baseline before the experimental foods are introduced and again 6 weeks into the intervention period and during the last week of the intervention (week 12)

Secondary Outcome Measures

blood pressure [12 weeks]
Participants will have their body weight and blood pressure taken at weekly counselling sessions
body composition [12 weeks]
body composition will be measured in well hydrated subjects using bioelectric impedence analysis
insulin resistance [12 weeks]
insulin resistance will be measured by way of an oral glucose tolerance test and collection of venous blood samples for the subsequent 3 hours on two occasions, baseline and during the last week of the intervention diet.
blood and urinary polyphenol metabolites [12 weeks]
venous blood and urine will be collected to determine the metabolic profiles of polyphenolics in individual participants. Based on intake data, the bioavailability of the polyphenols in the foods will be estimated.
circulating biomarkers of cardiovascular disease and type II diabetes risk [12 weeks]
Blood will be collected for measurement of multiple cytokines, growth factors and other blood biomarkers associated with these diseases.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 65 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

adult men and women 18-65 years of age
must have a least one of the following risk factors associated with increased risk of type II diabetes and/or cardiovascular disease:
borderline high or hypertension or undergoing treatment for such
abnormal fasting blood glucose or undergoing treatment for such
overweight or obese
borderline high or high LDL-cholesterol or undergoing treatment for such
borderline low or low HDL-cholesterol
borderline high or high triglycerides or undergoing treatment for such