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.

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.

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

The National Health and Nutrition Examination Survey (NHANES) is a cross-sectional, probability survey administered to the US civilian population aged from 0 to 85 years. This study used continuous NHANES data collected from 1999 to 2014, covering eight cycles of data collection (N=82,091). Participants were excluded from analysis for being under 18 (N=34,735) and not having data on either day of the 24-hour food intake (N=6,533). In an attempt to have a control group free of nut consumers, individuals who consumed peanuts, but not other nuts on the day of recall, were excluded from the analysis (N=6,702). After exclusions, our analytic sample N was 34,121, representing a population size of approximately 176 million individuals.