A Double Blind Study on the Gastrointestinal Effects of Arabinoxylan (Leaf Fiber Extract).

The study is a randomized, placebo-controlled, crossover, single-center trial with one screening visit (Visit 1; Week -1) and 3 test periods [Test Period 1 (Visits 2 and 3; Weeks 0 to 3), Test Period 2 (Visits 4 and 5; Weeks 5 to 8), and Test Period 3 (Visits 6 and 7; Weeks 10 to 13)] separated by minimum 2-week washout periods.

At Visit 1 (Week -1), subjects will provide informed consent and undergo assessments of medical history and prior, current medication/supplement use, and inclusion and exclusion criteria and a last menses query, where applicable. Additionally, height, body weight, and vital signs will be measured and BMI will be calculated. Fasting (12 ± 2 h) blood samples will be collected for chemistry and hematology, and female subjects will undergo an in-clinic urine pregnancy test. Subjects will be instructed to maintain physical activity and habitual diet as much as possible with the exception of excluding fermented foods or beverages that do or might contain live probiotics (e.g., yogurt, kombucha). Subjects will be dispensed a Baseline Diet Diary with instructions to record intake 7 days prior to Visit 2 (Week 0). Subjects will also be dispensed a Bowel Habits Diary and Daily GI Tolerance Questionnaire with instructions to complete these during the 7 days prior to Visit 2 (Week 0). Finally, subjects will be dispensed a stool collection kit and will be instructed to collect one fecal sample from one bowel movement during the 3 days prior to Visit 2 (Week 0). Subjects will be reminded that they are not required to fast prior to Visit 2 (Week 0) and will be encouraged to eat breakfast prior to their visit.

At Visit 2 (Week 0), subjects will arrive at the clinic to undergo clinic visit procedures (concomitant medication/supplement use, assess inclusion/exclusion criteria, body weight and vital signs measurements, last menses query, where applicable). Subjects will be queried about compliance with study instructions. The fecal sample will be collected and the Bowel Habits Diary, Baseline Diet Diary, and Daily GI Tolerance Questionnaire will be collected and reviewed. Subjects will be assigned to a randomization sequence. The first study product consumption will occur in the clinic and subject will be dispensed the remaining study products according to their assigned randomization sequence for home consumption (twice a day, once in the morning and once in the evening, with or without food). Subjects who consumed breakfast at home prior to arriving at the clinic will be administered the study product alone while those who did not consume breakfast prior to arriving at the clinic will be administered the study product with a snack. Subjects will also be dispensed a Study Product Diary to record study product intake. Subjects will be dispensed a copy of the last 5 days of their completed Baseline Diet Diary (reviewed at Visit 2, Week 0) and will be instructed to replicate the same food and beverage intake as closely as possible during the days prior to the collection of their fecal sample, which will occur during the 3 days immediately prior to Visit 3 (Week 3). Additionally, subjects will be dispensed 3-day Analysis Diet Records with instructions to record all food and beverages consumed during 3 days (2 weekdays and one weekend) following Visit 2 (Week 0) and before Visit 3 (Week 3) that do not coincide with the 5 replication days immediately prior to Visit 3 (Week 3). Subjects will be dispensed a Bowel Habits Diary and stool collection kit, and will be instructed to complete the Bowel Habits Diary during the 7 days immediately prior to Visit 3 (Week 3) and to collect a fecal sample from one bowel movement during the 3 days immediately prior to Visit 3 (Week 3). Subjects will also be dispensed a Daily GI Tolerance Questionnaire with instructions to complete the questionnaire daily starting from Visit 2 (Week 0) up to Visit 3 (Week 3). Finally, study instructions will also be provided [(i.e., overnight fasting (12 ± 2 h, water only), maintenance of physical activity with the exception of avoiding vigorous physical activity for 24 h prior; maintenance of habitual diet as much as possible with the exception of avoiding alcohol for 24 h prior and excluding fermented foods or beverages that do or might contain live probiotics (e.g., yogurt, kombucha) and consumption of study products].

At Visit 3 (Week 3), subjects will arrive at the clinic to undergo clinic visit procedures (concomitant medication/supplement use, assess inclusion/exclusion criteria, body weight, and vital signs measurements, last menses query, where applicable) and adverse event (AE) assessments. Subjects will be queried about compliance with study instructions and diet replication. Fasting (12 ± 2 h) blood samples will be collected for chemistry and hematology. Fecal samples will be collected and the Bowel Habits Diary, Daily GI Tolerance Questionnaire, and the 3-day Analysis Diet Record will be collected and reviewed. The Study Product Diary will be collected/reviewed, any unused study products will be collected, and compliance with study product consumption will be assessed. The Product Likeability Questionnaire will be administered in clinic. Subjects will be dispensed a stool collection kit and will be instructed to collect a fecal sample from one bowel movement during the 3 days immediately prior to Visit 4 (Week 5). Subjects will also be dispensed a copy of the last 5 days of their completed Baseline Diet Diary (reviewed at Visit 2, Week 0) and will be instructed to replicate the same food and beverage intake as closely as possible during the days prior to the collection of their fecal sample, which will occur during the 3 days immediately prior to Visit 4 (Week 5). Subjects will also be instructed to begin the 2-week washout period and return to the clinic to begin Test Period 2 at Visit 4 (Week 5). Finally, study instructions will also be provided [(i.e., maintenance of physical activity; maintenance of habitual diet as much as possible with the exception of excluding fermented foods or beverages that do or might contain live probiotics (e.g., yogurt, kombucha)]. Subjects will also be reminded that they are not required to fast prior to Visit 4 (Week 5) and will be encouraged to eat breakfast prior to their visit.

At Visit 4 (Week 5), subjects will return to the clinic, crossover to the other study product in their test sequence, and repeat the procedures from Visits 2 (Week 0) with the exception of the randomization procedure. At Visit 5 (Week 8), subjects will repeat the procedures from Visit 3 (Week 3), followed by a 2-week washout period before starting Test Period 3 at Visit 6 (Week 10). At Visit 6 (Week 10), subjects will return to the clinic, crossover to the other study product in their test sequence, and repeat the procedures from Visits 2 (Week 0) with the exception of the randomization procedure. Finally, at Visit 7 (Week 13), subjects will repeat the procedures from Visit 3 (Week 3).