The Addition of Whole Grains to the Diets of Middle-school Children

The Addition of Whole Grains to the Diets of Middle-school Children: A Study of Digestive Health and Immune Defenses

The Dietary Guidelines for Americans recommend that children and adolescents "consume whole-grain products often; at least half the grains should be whole grains." Few, if any studies, examine the benefit of whole grains on the health of adolescents. The purpose of this study is to determine if adolescents eating diets rich in whole grains vs. diets rich in refined grains (i.e., a typical diet) have improved markers of digestive and immune health.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Dietary supplement: Whole grain diet; Dietary supplement: Refined grain diet

Detailed Description

Middle-school students will be recruited and randomized to receive >/=80 g of whole grains (>/=5 servings) or similar foods made with refined grains each day for six weeks. Based on treatment group, subjects will be provided either whole grain or refined grain foods and snacks. They will be instructed on how to use these foods to replace other foods already contained in the diet. Stool, blood, and saliva samples will be obtained at baseline and at study end to examine the microbiota and markers of digestive and immune health. Daily records will be maintained by the students to assess bowel habits and compliance. It is anticipated that whole grains will increase stool bulk resulting in increased stool frequency and softer stools. Additionally, fermentation of the fiber within the colon will alter the microbiota profile. Because the majority of the immune system resides within the gastrointestinal tract, improved balance of the intestinal microbiota may prime the immune system thus contributing to improved immune defense.

• Study Type: Interventional
• Enrollment (Actual): 83
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Florida
    • Gainesville, Florida, United States, 32605
      • Westwood Middle School

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 11 years to 15 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Middle-school student at Westwood Middle School, Gainesville, FL
• Parental/guardian consent
• Willing to eat three different study foods each day for six weeks
• Willing to provide two blood samples and two saliva samples over the course of the study

Exclusion Criteria:

• Taking medications for constipation or diarrhea
• Antibiotic therapy within the past four weeks prior to randomization
• Takes probiotics or consumes greater than three servings of yogurt per week
• Has any diseases or illnesses such as gastrointestinal disease (gastric ulcers, Crohn's, ulcerative colitis, etc.), other chronic diseases (diabetes, kidney disease, etc.) or immune-modulating diseases (HIV, AIDS, autoimmune, hepatitis, cancer, etc.)
• Has any food allergies (wheat, soy, egg, milk, gluten, nuts, or any other food or food ingredient)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Whole grain diet; Participants in this group will be given whole grain snacks on school days and food packages consisting of whole grain breads, breakfast cereals, rice, snack foods, and pasta to replace their typical grains consumed at home.	Dietary supplement: Whole grain diet; Subjects were told to consume three different kinds of study food each day. The goal was an intake of greater than or equal to 80 g of whole grains per day.
Active Comparator: Refined grain diet; Participants in this group will be given refined grain snacks on school days and food packages consisting of refined grain breads, breakfast cereals, rice, snack foods, and pasta to replace their typical grains consumed at home.	Dietary supplement: Refined grain diet; The refined grain food products were matched as closely as possible to the foods contained in the whole grain diet. Subjects were told to consume three different kinds of study food each day.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Stool frequency	6 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in overall microbiota diversity	Microbial diversity will be measured by DGGE profiling to detect large distortions. Quantitative changes in the proportions of select bacteria will be measured using qPCR.	6 weeks
Inflammatory markers	Serum CRP, fibrinogen, IL-1, IL-6, and antioxidant capacity; mitogen-induced cytokine production including Th1, Th2, and inflammatory cytokines	6 weeks
Secretory IgA	Salivary and fecal sIgA	6 weeks

Collaborators and Investigators

• Sponsor: University of Florida
• Collaborators: General Mills

Publications and helpful links

General Publications

• Langkamp-Henken B, Nieves C Jr, Culpepper T, Radford A, Girard SA, Hughes C, Christman MC, Mai V, Dahl WJ, Boileau T, Jonnalagadda SS, Thielecke F. Fecal lactic acid bacteria increased in adolescents randomized to whole-grain but not refined-grain foods, whereas inflammatory cytokine production decreased equally with both interventions. J Nutr. 2012 Nov;142(11):2025-32. doi: 10.3945/jn.112.164996. Epub 2012 Sep 26.

Study record dates

Study Major Dates

• Study Start: February 1, 2010
• Primary Completion (Actual): April 1, 2010
• Study Completion (Actual): April 1, 2010

Study Registration Dates

• First Submitted: March 23, 2010
• First Submitted That Met QC Criteria: March 25, 2010
• First Posted (Estimate): March 29, 2010

Study Record Updates

• Last Update Posted (Estimate): August 2, 2012
• Last Update Submitted That Met QC Criteria: August 1, 2012
• Last Verified: July 1, 2012

More Information

Terms related to this study

• Keywords: Adolescent; Inflammation; Microbiota; Dietary fiber; Whole grain; Digestive health; Grain; Mucosal Immunity
• Other Study ID Numbers: 480-2009