The Effect of Fiber Snack Foods on Dietary Intake in Healthy Adults

The description of study activities is below:

Screening Period (approximately 2 weeks before randomization):

• Obtain height and weight
• Complete a 10-question survey about fruit, vegetable, and fiber intake
• Receive training on how to complete daily questionnaires online
• Complete the Global Physical Activity Questionnaire. This is a 16-question survey asking about physical activity in a typical week
• Complete the Eating Inventory. This is a 51-question survey that asks about your dietary habits and feelings related to food and eating
• Receive training on how to record your dietary intake using the ASA24. The ASA24 is a web-based interactive program that asks you to record the foods you ate during the previous day

Randomization:

• Measure weight, waist circumference, and body composition. We will use the BodPod to measure your body composition. The BodPod uses air displacement to measure body volume
• Receive dietary counseling on how to incorporate the study foods into your current diet. You will be asked to use these foods to replace foods you are currently eating
• Consume one study food per day for the first week and then 2 foods per day for weeks 2 through 8.
• Complete the 10-question online daily survey
• Complete 7 days of 24-hour dietary recalls using the ASA24 during weeks 4, 6, and 8

Final:

• Return any uneaten study foods.
• Measure weight, waist circumference, and body composition
• Complete the Global Physical Activity Questionnaire (GPAQ) and the Eating Inventory

Inclusion criteria

• Adults 18 to 50 years of age
• Internet access for the duration of the protocol
• BMI of 23.0 to < 30 kg/m2
• Usual fiber intake of <20 g/d based on FFQ such as the Block Fruit/Vegetable/Fiber Screener
• Weight stable (±5 lbs. last 3 months)
• Assessment of normal eating determined by the Eating Inventory
• Willing to eat yogurt and a granola-like snack bar daily for 8 weeks
• Willing to complete daily questionnaires and 28 dietary recalls over the 8 weeks
• Habitual breakfast consumer defined as eating breakfast (any food within 2 hours of waking) 5 or more days a week
• Willing to provide a social security number to receive study payment

Exclusion criteria

• Post-menopausal (self-reported no menstrual period for one year)
• Current smokers or tobacco users
• Based on Automated Self-Administered Diet History (ASA24) dietary intake data collected during pre-baseline period: Females eating less than 1200 kcal/day, males eating less than 1500 kcal/day or either or greater than 4000 kcal per day, consuming on average greater than 10 g dietary fiber/1000 kcal
• Unwilling to discontinue any prebiotic and fiber supplements, or probiotic supplement
• Antibiotic use within 2 months from study start
• Known food allergies
• Physician-diagnosed gastrointestinal disease or condition (such as ulcerative colitis, Crohn's disease, gastroparesis, cancer, peptic ulcer disease, Celiac disease, short bowel disease, ileostomy, colostomy other than GERD, constipation, diverticular disease)
• Taking prescribed medications other than oral contraceptives, seasonal allergy medications, cholesterol or blood pressure lowering medications, vitamins or minerals, baby aspirin
• Intake of >2 alcoholic drinks per day on average
• Purposeful exercise of >300 minutes per week on average
• Women who are lactating or know they are pregnant