A Grapefruit Feeding Trial in Healthy, Overweight Adults

Sponsor

University of Arizona (Other)

Overall Status

Completed

CT.gov ID

NCT01452841

Collaborator

Texas A&M University (Other)

Enrollment

Location

Arms

Duration (Months)

4.3

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Folklore has suggested that consuming grapefruit may promote weight control. Sparse data exist to support this hypothesis, though there is some evidence of health promotional effects regarding blood pressure and lipid profiles. The aims of this randomized controlled trial are to determine the role of grapefruit in:

Reducing weight
Reducing blood pressure
Reducing inflammation
Improving the lipid profile.

The investigators hypothesize that six weeks of daily consumption of grapefruit will reduce weight, blood pressure, and inflammation while improving the lipid profile in overweight, healthy adults.

Condition or Disease	Intervention/Treatment	Phase
Weight Loss Obesity Cardiovascular Risk Factors	Other: Grapefruit Other: Control	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

85 participants

Allocation:

Randomized

Intervention Model:

Single Group Assignment

Masking:

None (Open Label)

Primary Purpose:

Prevention

Official Title:

Efficiency of Daily Grapefruit Exposure in Reducing Body Weight and Inflammatory Markers

Study Start Date :

Aug 1, 2009

Actual Primary Completion Date :

Apr 1, 2011

Actual Study Completion Date :

Apr 1, 2011

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Grapefruit Consumption	Other: Grapefruit 1.5 Rio Red Grapefruit consumed daily for 6 weeks
Active Comparator: Control	Other: Control Participants followed a diet low in bioactive rich fruits and vegetables and avoided citrus for six weeks

Arm

Intervention/Treatment

Experimental: Grapefruit Consumption

Other: Grapefruit

1.5 Rio Red Grapefruit consumed daily for 6 weeks

Active Comparator: Control

Other: Control

Participants followed a diet low in bioactive rich fruits and vegetables and avoided citrus for six weeks

Outcome Measures

Primary Outcome Measures

Weight reduction [6 weeks]
Participants consumed 1/2 grapefruit before each meal (1.5 grapefruit per day) for six weeks. Weight was measured before and after grapefruit consumption to assess weight change. Weight change was considered statistically significant at p<0.05.

Secondary Outcome Measures

Blood pressure reduction [6 weeks]
Previous studies in animals and humans consuming citrus have resulted in reductions in blood pressure, though no direct effect of grapefruit has ever been demonstrated. Blood pressure was measured at baseline and after the 6 week intervention period (consuming either the control diet or supplementing the diet with 1/2 grapefruit before each meal).
Lipid Profile Improvements [6 weeks]
Previous studies in humans and animal models consuming grapefruit or grapefruit bioactives have shown reductions in triglycerides, LDL, and total cholesterol and increases in circulating HDL. These parameters were measured via a common point-of-care system, LDX Cholestech. Lipids were measured at baseline and after the 6 week intervention period (consuming either the control diet or supplementing the diet with 1/2 grapefruit before each meal).
Reductions in markers of chronic inflammation [6 weeks]
Markers of chronic inflammation, which are also associated with endothelial dysfunction and heart disease, like tumor necrosis factor alpha (TNFalpha), interleukin-1beta (IL-1beta), and soluble vascular cellular adhesion molecule-1 (sV-CAM1) were measured. Inflammatory markers were measured at baseline and after the 6 week intervention period (consuming either the control diet or supplementing the diet with 1/2 grapefruit before each meal).

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Adults, men and premenopausal women
BMI: 25-45 kg/m2
Willing to maintain current exercise regimen (not to exceed 10 hours/week)
Willing to follow a diet low in bioactive rich fruits and vegetables and with no citrus