The purpose of this research study is to determine whether a functional fiber, galactooligosaccharide, can help maintain immune strength and digestive health in undergraduate students who are undergoing an academic stress (i.e., final exams). Subjects will be asked to consume the fiber or placebo each day for eight weeks. Immune and gastrointestinal health will be evaluated via daily questionnaires obtained from 420 students and from the collection of fecal samples in a subgroup of students.

A prospective, randomized, parallel, double-blind, placebo controlled design will be used. Healthy full-time undergraduate students undergoing fall 2009 final academic exams will be recruited from the University of Florida. Informed consent will be obtained. All subjects will be consented for the main intervention study and a subgroup (n=25/group or 75 total) of these subjects will also be consented to provide two stool samples at baseline and two stool samples during the week of final exams (approximately week 4 of the intervention). Subjects will be stratified based on gender and randomized (n=140/group) to receive 0 g, 2.5 g, or 5.0 g of the fermentable fiber, galactooligosaccharides, for eight weeks around the time of their fall final exams. Subjects will complete daily online questionnaires asking whether they are experiencing any cold/flu symptoms. Weekly online questionnaires will collect information regarding gastrointestinal symptoms over the past week. The acute psychological stress associated with final exams will increase cold/flu symptoms. It is anticipated that students consuming the galactooligosaccharides versus the placebo will have more healthy days (i.e., days without cold symptoms) due to fiber induced changes in the beneficial bacteria within the colon, which reduces the burden on the immune system.

Inclusion Criteria:

• 18 years of age or older
• willing to complete a daily assessment form via computer
• willing to discontinue any immune-enhancing dietary supplements ( e.g., prebiotics and fiber supplements, probiotics, echinacea, fish oil, vitamin E >100% of the RDA or >15 mg/day)
• willing to take the fiber for 8 weeks
• had a cold in last 12 months
• have at least 1 final during the Fall 2009 exam week, between Saturday, December 12 and Friday, December18, 2009
• daily access to a computer with Internet access for the entire 8-wk study

Exclusion Criteria:

• current smoker
• chronic allergies involving the upper respiratory tract (Chronic = taking allergy medicine daily)
• an allergy to milk
• known illnesses or conditions that may impact perceived health such as HIV/AIDS, diabetes, renal or gastrointestinal diseases
• received chemotherapy or other immune suppressing therapy within the last year
• antibiotic therapy in the past two months
• a cold or cold symptoms (on day of randomization)