The purpose of this study is to examine whether older adults taking a fruit/vegetable supplement for 6 weeks will modify the biochemical values of stool, blood, and urine to be similar to those of younger adults. Participants will be asked to consume prepackaged study meals provided by the Center for approximately 8 weeks and to provide blood, stool, and urine samples on 2 separate occasions.
Men and women aged 55 years and older
• BMI < 26 and > 40 kg/m2
• Vegetarians or vegans
• Pregnant or breastfeeding
• Allergy to any plant foods
• Irregular bowel movements (<3 times per week)
• Diabetes, kidney or gastrointestinal disease, rheumatoid arthritis, gout
• Alcohol consumption of 2 or more drinks per day
• Fruit and vegetable consumption <3 times daily; however if consuming <6 servings of fruits and vegetables daily, must be willing to reduce intake to <3 servings prior to enrollment.
Length of Study
Approximately 8 weeks
Number of Visits
1 screening visit; 6 study visits for collection of blood, urine, stool samples, as well as collecting dietary and clinical information (i.e., blood pressure, weight, etc.), and to pick up prepackaged meals.
Can I work?
All foods and beverages will be provided during the 8-week period. The study meals will be comprised of mostly foods that are typical to the diet that average Americans are consuming daily.
Participants must be willing to stop all dietary supplements for the duration of the study, except for the fruit/vegetable supplements provided on the study for 6 weeks.
$480 for participants who qualify and complete the entire study → $25 for screening, and up to $600 for participants who qualify and complete the entire study
Length of study
Total length of the study including resident stays and nonresident visits.
This does not mean you will be testing the entire time.
The length of time volunteers are required to stay overnight at the HNRCA. Residents have their own private room, bathroom, television, VCR, and phone during their stay.
The amount of reimbursement for travel and inconvenience.
Number of visits
Total number of nonresident visits.
Indicates meals which will be provided by the HNRCA
Can I work?
Indicates if you will be able to work and if so, when.
For more information about this study, please call Volunteer Services at 1-800-738-7555.
We appreciate your interest in our program and we hope to work with you in the future.
The Recruitment Office
Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University