Effect of Red Raspberry Consumption on Fasting Oxidative Stress Biomarkers

Raspberries and Human Health: A Short-term Intervention Trial Investigating the Effect of Daily Red Raspberry Consumption on Fasting Oxidative Stress Biomarkers

The purpose of this study is determine whether daily consumption of frozen red raspberries can improve the antioxidant capacity of the blood and reduce the effects of oxidative stress, dose-dependently, in a healthy adult population.

Study Overview

• Status: Completed
• Conditions: Oxidative Stress
• Intervention / Treatment: Dietary supplement: individually quick frozen red raspberries; Dietary supplement: individually quick frozen red raspberries; Dietary supplement: individually quick frozen red raspberries

Detailed Description

Red raspberries are an excellent source of numerous polyphenolic antioxidants. The bioactivity of these compounds have been implicated in many biological pathways and may function to reduce the risk of numerous chronic diseases. We are conducting an intervention study with frozen red raspberries on a healthy adult population in order to determine if raspberry polyphenols are bioavailable and bioactive in vivo. Twenty-four subjects (12 male and 12 female) will be recruited to participate and consume one-cup frozen red raspberries daily for two weeks, they then will randomly be assigned to consume either one, two or four cups of raspberries for another two weeks, this will be followed by four weeks of non-treatment. Blood samples and 12-hour urine collections will be taken in order to measure the concentration of raspberry polyphenols in response to treatment dose. Dose-dependent treatment effects on blood biomarkers for antioxidant capacity, oxidative stress, inflammation and other chronic disease risk factors will also be measured.

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Phase 1

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5C 2T2
      • Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 43 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• healthy adults

Exclusion Criteria:

• obese (>30kg/m2)
• high blood pressure (140/90mmHg)
• allergic to raspberries
• pregnant or lactating
• history of chronic disease
• currently taking medication

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: one-cup	Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries daily for four weeks, followed by a four week period of non-treatment.; Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries for two weeks, then consumption of two-cups frozen red raspberries for an additional two weeks, followed by four weeks of non-treatment.; Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries for two weeks, then consumption of four-cups frozen red raspberries for an addition two weeks, followed by four weeks of non-treatment.
Experimental: two-cups	Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries daily for four weeks, followed by a four week period of non-treatment.; Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries for two weeks, then consumption of two-cups frozen red raspberries for an additional two weeks, followed by four weeks of non-treatment.; Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries for two weeks, then consumption of four-cups frozen red raspberries for an addition two weeks, followed by four weeks of non-treatment.
Experimental: four-cups	Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries daily for four weeks, followed by a four week period of non-treatment.; Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries for two weeks, then consumption of two-cups frozen red raspberries for an additional two weeks, followed by four weeks of non-treatment.; Dietary supplement: individually quick frozen red raspberries; Consumption of one-cup frozen red raspberries for two weeks, then consumption of four-cups frozen red raspberries for an addition two weeks, followed by four weeks of non-treatment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
serum TBARS	an indicator of MDA levels, and therefore, lipid peroxidation	end of week 1, 3, 5 and 9

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
serum antioxidant capacity (AOC)	measured using the TEAC-ABTS radical cation assay	end of week 1, 3, 5 and 9
serum thiols	measured using the DTNB assay, as an indicator of antioxidant levels in protein fraction	end of week 1, 3, 5 and 9

Collaborators and Investigators

• Sponsor: University of Toronto
• Collaborators: Unity Health Toronto
• Investigators: Principal Investigator: A V Rao, PhD, Department of Nutritional Sciences, University of Toronto

Study record dates

Study Major Dates

• Study Start: March 1, 2009
• Primary Completion (Actual): May 1, 2009
• Study Completion (Actual): May 1, 2009

Study Registration Dates

• First Submitted: April 3, 2009
• First Submitted That Met QC Criteria: April 3, 2009
• First Posted (Estimate): April 7, 2009

Study Record Updates

• Last Update Posted (Estimate): October 29, 2010
• Last Update Submitted That Met QC Criteria: October 28, 2010
• Last Verified: October 1, 2010

More Information

Terms related to this study

• Keywords: oxidative stress; antioxidants; polyphenols; dietary intervention; fruit; raspberry
• Other Study ID Numbers: 22069