MNT: Gastrointestinal Disorders (2015
Citation:
Lee AR, Ng DL, Dave E, Ciaccio EJ, Green PHR. 2009. The effect of substituting alternative grains in the diet on the nutritional profile of the gluten-free diet. J Hum Nutr Diet, 22, pp. 359-363. doi: 10.1111/j.1365-277X.2009.00970.x
PubMed ID: 19519750
Study Design:
Retrospective Cohort Study
Class:
B - Click here for explanation of classification scheme.
Quality Rating:

Research Purpose:
To determine whether the nutritional profile of a gluten-free diet could be improved through the use of alternative grains.
Inclusion Criteria:
Not specified by authors.
Exclusion Criteria:
Not specified by authors.
Description of Study Protocol:
Recruitment
50 patients of the Celiac Disease Center were randomly selected to participate in the study.Design
- In this retrospective review of diet history, 50 randomly selected patients from the Celiac Disease Center at Columbia University provided the dietitian with a three-day food diary of their usual intakes
- The grain/starch choices were recorded by grain category, number of servings of grains and meal at which grain was consumed
- Intake patterns from the 50 food diaries were averaged together to create one average intake pattern
- The alternative gluten-free diet pattern was created by substituting only the grain or starch portion of the standard menu pattern with alternative gluten-free grains or grain products. This alternative pattern used oats at breakfast, high-fiber brown rice bread at lunch and quinoa as a starch side dish at dinner. The grain choices were then analyzed for nutrient content comparing both the standard and alternative diet pattern.
Statistical Analysis
ANOVA and paired T-tests were used to identify statistical significance between the standard and alternative gluten-free diet patterns.
Data Collection Summary:
- Timing of measurements: Three-day food diaries were retrospectively reviewed by the dietitian
- Dependent variables: Three-day food diaries self-reported by patients
- Independent variables: Substituting the grain or starch portion of the average meal pattern with alternative gluten-free grains (oats at breakfast, high-fiber brown rice bread at lunch and quinoa at dinner)
- Control variables: Only the grain choices were analyzed for the nutrient content comparing both the standard and alternative diet pattern.
Description of Actual Data Sample:
- Initial N: 50 patients
- Attrition (final N): None specified by authors
- Age: Not specified
- Ethnicity: Not specified
- Other relevant demographics: Not specified
- Anthropometrics: Not specified
- Location: Celiac Disease Center, Columbia University, New York.
Summary of Results:
Key Findings
- The standard gluten-free diet did not meet the USDA's recommended six to 11 servings of grains per day
- Standard gluten-free diet grains consisted of 44% rice (predominately white), 8% potato, 5% oats, 3% corn, 1% Buckwheat and 1% quinoa; 38% consumed no grains; 55% of snacks comprised commmercially prepared snacks (chips, pretzels, GF cookie, donuts and cake)
- The alternative diet pattern provided an improved nutrient profile compared to the standard gluten-free diet (P=0.0002)
- The change in dietary grains significantly increased protein (20.6g vs. 11g), iron (18.4mg vs. 1.4mg), calcium (182mg vs. 0.0mg) and fiber (12.7g vs. 5.0g).
Author Conclusion:
- Changing the grains in a gluten-free diet has the potential to improve the nutritional profile of the diet for individuals with celiac disease
- Patients and their dietary counselors require education on alternative sources to diversify the standard gluten-free diet.
Funding Source:
University/Hospital: | Celiac Disease Center, School of Medicine, Columbia University |
Reviewer Comments:
- Although the authors stated that selected nutrient levels significantly increased with changing the dietary grains (i.e., iron, calcium, fiber and protein), they did not provide a P-value for each nutrient. The only P-value provided was for an overall improved nutrient profile.
- The authors do state limitations of the study: These include a population bias because the diet history records were provided by individuals attending a large celiac disease center, a small sample size (N=50), limited nutritional analysis and the potential inaccuracies of reported food intakes.
Quality Criteria Checklist: Primary Research
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Relevance Questions | |||
1. | Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies) | Yes | |
2. | Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about? | Yes | |
3. | Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice? | Yes | |
4. | Is the intervention or procedure feasible? (NA for some epidemiological studies) | Yes | |
Validity Questions | |||
1. | Was the research question clearly stated? | Yes | |
1.1. | Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified? | Yes | |
1.2. | Was (were) the outcome(s) [dependent variable(s)] clearly indicated? | Yes | |
1.3. | Were the target population and setting specified? | Yes | |
2. | Was the selection of study subjects/patients free from bias? | ??? | |
2.1. | Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study? | No | |
2.2. | Were criteria applied equally to all study groups? | ??? | |
2.3. | Were health, demographics, and other characteristics of subjects described? | No | |
2.4. | Were the subjects/patients a representative sample of the relevant population? | ??? | |
3. | Were study groups comparable? | N/A | |
3.1. | Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT) | N/A | |
3.2. | Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? | N/A | |
3.3. | Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.) | N/A | |
3.4. | If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis? | N/A | |
3.5. | If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.) | N/A | |
3.6. | If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")? | N/A | |
4. | Was method of handling withdrawals described? | N/A | |
4.1. | Were follow-up methods described and the same for all groups? | N/A | |
4.2. | Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.) | N/A | |
4.3. | Were all enrolled subjects/patients (in the original sample) accounted for? | ??? | |
4.4. | Were reasons for withdrawals similar across groups? | N/A | |
4.5. | If diagnostic test, was decision to perform reference test not dependent on results of test under study? | N/A | |
5. | Was blinding used to prevent introduction of bias? | No | |
5.1. | In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate? | N/A | |
5.2. | Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.) | N/A | |
5.3. | In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded? | No | |
5.4. | In case control study, was case definition explicit and case ascertainment not influenced by exposure status? | N/A | |
5.5. | In diagnostic study, were test results blinded to patient history and other test results? | N/A | |
6. | Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described? | Yes | |
6.1. | In RCT or other intervention trial, were protocols described for all regimens studied? | Yes | |
6.2. | In observational study, were interventions, study settings, and clinicians/provider described? | N/A | |
6.3. | Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect? | Yes | |
6.4. | Was the amount of exposure and, if relevant, subject/patient compliance measured? | N/A | |
6.5. | Were co-interventions (e.g., ancillary treatments, other therapies) described? | N/A | |
6.6. | Were extra or unplanned treatments described? | N/A | |
6.7. | Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups? | N/A | |
6.8. | In diagnostic study, were details of test administration and replication sufficient? | N/A | |
7. | Were outcomes clearly defined and the measurements valid and reliable? | Yes | |
7.1. | Were primary and secondary endpoints described and relevant to the question? | Yes | |
7.2. | Were nutrition measures appropriate to question and outcomes of concern? | Yes | |
7.3. | Was the period of follow-up long enough for important outcome(s) to occur? | Yes | |
7.4. | Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures? | Yes | |
7.5. | Was the measurement of effect at an appropriate level of precision? | Yes | |
7.6. | Were other factors accounted for (measured) that could affect outcomes? | Yes | |
7.7. | Were the measurements conducted consistently across groups? | N/A | |
8. | Was the statistical analysis appropriate for the study design and type of outcome indicators? | Yes | |
8.1. | Were statistical analyses adequately described and the results reported appropriately? | Yes | |
8.2. | Were correct statistical tests used and assumptions of test not violated? | Yes | |
8.3. | Were statistics reported with levels of significance and/or confidence intervals? | Yes | |
8.4. | Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)? | N/A | |
8.5. | Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)? | N/A | |
8.6. | Was clinical significance as well as statistical significance reported? | Yes | |
8.7. | If negative findings, was a power calculation reported to address type 2 error? | N/A | |
9. | Are conclusions supported by results with biases and limitations taken into consideration? | Yes | |
9.1. | Is there a discussion of findings? | Yes | |
9.2. | Are biases and study limitations identified and discussed? | Yes | |
10. | Is bias due to study's funding or sponsorship unlikely? | Yes | |
10.1. | Were sources of funding and investigators' affiliations described? | Yes | |
10.2. | Was the study free from apparent conflict of interest? | Yes | |