Citrus Beverages and Gastrointestinal Function

In this randomized, double-blind, controlled trial, healthy adults will be asked to consume
daily servings of orange juice containing either 0 g (n=120; control) or 180 g (i.e. 10 g
fiber; n=120) of orange pomace for 3 weeks to assess the effect of the pomace on stool
frequency. Blood samples will be obtained to assess the effect of the pomace on metabolic
markers. Stool samples will be collected for analyses of the effect of the pomace on fecal
bacteria known to be associated with health benefits (e.g., bifidobacteria). For exploratory
analyses, additional groups will be asked to consume orange juice containing 90 g of pomace
(i.e. 5 g fiber; n=40) or orange-flavored, calorie-matched water (n=40); outcomes from the
water group will be compared to those of the 0 g pomace juice group to assess any effects of
the juice alone, and outcomes from the 90 g pomace group will be compared to those of the 180
g and 0 g groups in microbiota analyses.

Inclusion Criteria:

- Healthy adults 18-60 years of age

- Willing and able to consume 16 oz. of a citrus beverage daily for the 3-week study
intervention

- Willing and able to avoid consumption of any orange, grapefruit, tomato or V-8 juice
and whole oranges or grapefruits during the two weeks leading up to the study and
during the study, not including the study beverage

- Willing and able to complete daily questionnaires online regarding dietary intake and
general health and well-being, including gastrointestinal habits Note: we will recruit
participants who will have Internet access for the duration of the protocol, but
understand that, once enrolled, situations may change. If this is the case, paper
copies of the online forms will be provided

- Willing to discontinue any prebiotic, probiotic, and fiber supplements after
consenting

- Willing to provide blood via finger prick and a stool sample twice each, once at the
beginning and once at the end of the study

Exclusion Criteria:

- Women who are lactating, know that they are pregnant, or are attempting to get
pregnant

- Currently being treated for any physician-diagnosed diseases or conditions

- Vegetarians/vegans