Evaluating Liking, Acceptability and Health Benefits of Grain Products (FL75)

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.

Study Overview

• Status: Completed
• Conditions: Food Preferences
• Intervention / Treatment: Other: Whole grain foods; Other: 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.

• Study Type: Interventional
• Enrollment (Actual): 45
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Davis, California, United States, 95616
      • Western Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 20-45 years of age
• male or female
• consumers of 1 or fewer whole grain products per day

Exclusion Criteria:

• 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 Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Whole Grain; 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.	Other: Whole grain foods; Eight commonly consumed whole grain products that meet the consumers Dietary Guidelines recommendations for a period of six weeks.
Placebo Comparator: Refined Grains; Time control compared to experimental intervention.	Other: Refined grains; Eight commonly consumed refined grain products given in amounts that fulfill the consumer's Dietary Guidelines for Americans recommendation over the course of six weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in the acceptability and liking of grain products	Sensory evaluation of grain products	0, 6 weeks
Change in the gut microbiota and their fermentation products	To determine if gut microbiota change over the intervention and if those changes persist over the long term. Gut microbiota assessed using 16S methodology.	0, 6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in gastrointestinal function	Change in gastrointestinal function assessed using a questionnaire and exhaled breath hydrogen (ppm).	0, 6 weeks
Liking the taste of grain products	Implicit Attitude Tests assessed using a calculated D score using the method described by Greenwald et al.	0, 6 weeks

Collaborators and Investigators

• Sponsor: USDA, Western Human Nutrition Research Center
• Investigators: Principal Investigator: Nancy Keim, PhD, USDA, Western Human Nutrition Research Center; Study Director: William Horn, MS, USDA, Western Human Nutrition Research Center

Publications and helpful links

General Publications

• Greenwald AG, Nosek BA, Banaji MR. Understanding and using the implicit association test: I. An improved scoring algorithm. J Pers Soc Psychol. 2003 Aug;85(2):197-216. doi: 10.1037/0022-3514.85.2.197.
• Cooper DN, Kable ME, Marco ML, De Leon A, Rust B, Baker JE, Horn W, Burnett D, Keim NL. The Effects of Moderate Whole Grain Consumption on Fasting Glucose and Lipids, Gastrointestinal Symptoms, and Microbiota. Nutrients. 2017 Feb 21;9(2):173. doi: 10.3390/nu9020173.
• Cooper DN, Martin RJ, Keim NL. Does Whole Grain Consumption Alter Gut Microbiota and Satiety? Healthcare (Basel). 2015 May 29;3(2):364-92. doi: 10.3390/healthcare3020364.
• De Leon A, Burnett DJ, Rust BM, Casperson SL, Horn WF, Keim NL. Liking and Acceptability of Whole Grains Increases with a 6-Week Exposure but Preferences for Foods Varying in Taste and Fat Content Are Not Altered: A Randomized Controlled Trial. Curr Dev Nutr. 2020 Mar 9;4(3):nzaa023. doi: 10.1093/cdn/nzaa023. eCollection 2020 Mar.

Helpful Links

• Western Human Nutrition Research Center website

Study record dates

Study Major Dates

• Study Start: April 1, 2010
• Primary Completion (Actual): October 1, 2013
• Study Completion (Actual): December 1, 2013

Study Registration Dates

• First Submitted: July 5, 2011
• First Submitted That Met QC Criteria: July 25, 2011
• First Posted (Estimated): July 27, 2011

Study Record Updates

• Last Update Posted (Actual): March 12, 2024
• Last Update Submitted That Met QC Criteria: March 8, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Keywords: Acceptability; liking
• Other Study ID Numbers: WHNRC 235561-1