Walnut Consumption and Diabetes Risk

Study Overview
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Brief Summary
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Multiple NHANES surveys were combined and weighted to evaluate relationships between walnut consumption and type 2 diabetes mellitus using various independent measures of diabetes status and risk. After risks were ascertained, interactions with gender were analyzed.

Detailed Description
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Background. Dietary interventions and cohort studies of tree nuts lowering glucose levels for diabetes suggest a possible effect with walnuts. Objective. To examine the associations between walnut consumption and diabetes risk through data from the National Health and Nutrition Examination Survey (NHANES). Methods. NHANES survey data for 1999 through 2014 was pooled for adults with 24 hour recall dietary data. Risk of diabetes was based on self-report, medication use, fasting plasma glucose levels, and hemoglobin A1c (HbA1c) levels. Individuals were characterized as reporting consumption of walnuts, mixed 'nuts', or no nuts.

Official Title
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Association Between Walnut Consumption and Diabetes Risk in NHANES May be Gender Sex Specific

Conditions
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Diabetes Mellitus

Intervention / Treatment
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* Diagnostic Test: Diabetes Outcome


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: NHANES data from 1999-2014 with food recalls and dietary food intake Exclusion Criteria: not having data on either day of the 24-hour food intake individuals who consumed peanuts, but not other nuts on the day of recall, were excluded from the analysis

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Nuts<br>All other foods that did not include walnuts or other nuts were classified as no nuts (NN). | Diagnostic Test: Diabetes Outcome<br>* based on self report definition, fasting plasma glucose, and hemoglobin A1c<br>|
| Other Nuts<br>Foods codes describing nuts that are not walnuts (i.e. cashew nuts, pistachios, etc.) or nut-containing foods that do not commonly contain walnuts (e.g. granola) were classified as other nuts (ON). | Diagnostic Test: Diabetes Outcome<br>* based on self report definition, fasting plasma glucose, and hemoglobin A1c<br>|
| Walnuts with other nuts<br>food codes describing nut mixes and foods that commonly include walnuts were classified as walnuts with other nuts (WwON) | Diagnostic Test: Diabetes Outcome<br>* based on self report definition, fasting plasma glucose, and hemoglobin A1c<br>|
| Walnuts with high certainty<br>Foods consisting entirely or mostly of walnuts were classified as walnuts with high certainty (WwHC) | Diagnostic Test: Diabetes Outcome<br>* based on self report definition, fasting plasma glucose, and hemoglobin A1c<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diabetes Outcome- self report | Based on self-report as told by a doctor | 1999-2014 | 
| Diabetes Outcome- Fasting Plasma Glucose | Based on FPG levels | 1999-2014 | 
| Diabetes Outcome- Hemoglobin A1c | Based on HbA1c levels | 1999-2014 | 
| Diabetes Outcome- Combined Definition | Based on both FPG and HbA1c levels | 1999-2014 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sex Interaction | based on the previously stated definition outcomes | 1999-2014 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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nut consumption, NHANES, epidemiology, plasma glucose, hemoglobin A1c