Evaluating Liking, Acceptability and Health Benefits of Grain Products
- Conditions
- Food Preferences
- Interventions
- Other: Whole grain foodsOther: Refined grains
- Registration Number
- NCT01403857
- Lead Sponsor
- USDA, Western Human Nutrition Research Center
- Brief Summary
The specific aims of the Grain Study are to determine if exposure to different types of grain products, over a period of 6 weeks, changes liking and acceptability and to determine if the gut microbiota, bacterial fermentation products, or gastrointestinal function changes with consumption of whole grains or refined grains.
- Detailed Description
Subjects will be recruited in accordance with inclusion and exclusion criteria listed below. Subjects will be assigned to one of two different grain product 'exposure' groups - Group 1 will receive predominantly Whole Grain (WG) products and Group 2 will receive predominantly Refined Grain (RG) products (ratio of WG to RG assignment will be 2:1). For a 6-week exposure period, subjects will receive weekly market baskets of grain products consisting of breakfast cereals, breads, snack items, and side dishes with the target of providing whole grains at a level of 85% of grain intake for the WG group (this exceeds the current Dietary Guideline recommendation of 50%) and 15% for the RG group (this is the current estimated intake for U.S. adults). Before and after grain exposure, subjects will rate the acceptability and liking of numerous grain products. To accomplish this, subjects will participate in sensory evaluation tests using these products, and they will provide information using validated questionnaires and take implicit association tests. During the 6-week study period, subjects will record use of the market basket grain products, and provide subjective scores for taste, convenience, nutrition, and general liking. The quality of the total dietary intake will be assessed using unannounced 24-h recalls. Biological samples will also be collected from subjects. Blood and urine samples will be collected to evaluate risk factors of chronic disease, and biomarkers of whole grain intake, fruits and vegetables. Saliva and fecal samples will be collected to measure changes in gut microbiota and to measure metabolites of bacterial fermentation. Breath hydrogen tests will be conducted to measure bacterial fermentation. Two weeks after the end of the intervention period, subjects will participate in a nominal group session to identify significant barriers and facilitators to inclusion of grain products into their diets.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 45
- 20-45 years of age
- male or female
- consumers of 1 or fewer whole grain products per day
- Type I or II Diabetes or glucose intolerance
- Preference for whole grains
- Do not cook at home
- Pregnant or planning to be pregnant
- Smoking
- Chronic inflammatory bowel disease
- colorectal cancer
- Celiac disease or gluten sensitivity
- Crohn's disease
- Regular use of colonics and/or laxatives
- body weight change of >3% in last 6 months
- use of antibiotics, appetite suppressants, mood altering medications, and regular tobacco use.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Whole Grain Whole grain foods Whole grain products as defined by the American Association of Cereal Chemists (AACC) given in a market basket that contains eight commonly used grain products over six weeks. Refined Grains Refined grains Time control compared to experimental intervention.
- Primary Outcome Measures
Name Time Method Change in the acceptability and liking of grain products 0, 6 weeks Sensory evaluation of grain products
Change in the gut microbiota and their fermentation products 0, 6 weeks To determine if gut microbiota change over the intervention and if those changes persist over the long term. Gut microbiota assessed using 16S methodology.
- Secondary Outcome Measures
Name Time Method Change in gastrointestinal function 0, 6 weeks Change in gastrointestinal function assessed using a questionnaire and exhaled breath hydrogen (ppm).
Liking the taste of grain products 0, 6 weeks Implicit Attitude Tests assessed using a calculated D score using the method described by Greenwald et al.
Trial Locations
- Locations (1)
Western Human Nutrition Research Center
🇺🇸Davis, California, United States