Walnut Consumption and Diabetes Risk

Sponsor

University of California, Los Angeles (Other)

Overall Status

Completed

CT.gov ID

NCT03224533

Collaborator

California Walnut Commission (Other)

34,121

Enrollment

Location

Actual Duration (Months)

1424.6

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

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.

Condition or Disease	Intervention/Treatment	Phase
Diabetes Mellitus	Diagnostic Test: Diabetes Outcome

Detailed Description

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.

Study Design

Study Type:

Observational

Actual Enrollment :

34121 participants

Observational Model:

Case-Control

Time Perspective:

Cross-Sectional

Official Title:

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

Actual Study Start Date :

Jun 1, 2015

Actual Primary Completion Date :

May 30, 2017

Actual Study Completion Date :

May 30, 2017

Arms and Interventions

Arm	Intervention/Treatment
No Nuts All other foods that did not include walnuts or other nuts were classified as "no nuts" (NN).	Diagnostic Test: Diabetes Outcome based on self report definition, fasting plasma glucose, and hemoglobin A1c
Other Nuts 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 based on self report definition, fasting plasma glucose, and hemoglobin A1c
Walnuts with other nuts food codes describing nut mixes and foods that commonly include walnuts were classified as "walnuts with other nuts" (WwON)	Diagnostic Test: Diabetes Outcome based on self report definition, fasting plasma glucose, and hemoglobin A1c
Walnuts with high certainty Foods consisting entirely or mostly of walnuts were classified as "walnuts with high certainty" (WwHC)	Diagnostic Test: Diabetes Outcome based on self report definition, fasting plasma glucose, and hemoglobin A1c

Outcome Measures

Primary Outcome Measures

Diabetes Outcome- self report [1999-2014]
Based on self-report as told by a doctor
Diabetes Outcome- Fasting Plasma Glucose [1999-2014]
Based on FPG levels
Diabetes Outcome- Hemoglobin A1c [1999-2014]
Based on HbA1c levels
Diabetes Outcome- Combined Definition [1999-2014]
Based on both FPG and HbA1c levels

Secondary Outcome Measures

Sex Interaction [1999-2014]
based on the previously stated definition outcomes

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 80 Years

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Yes

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