Adding Walnuts to the Diet of Children and Adolescents Improved the Diet Quality: Results of an NHANES Modeling Study

OBJECTIVES: To assess the impact of adding one ounce of walnuts on nutrients of public health concern and diet quality. METHODS: Food modeling was implemented in the nationally representative 2015–2018 National Health and Examination Survey (NHANES) in a population of 4,756 children and adolescents of no-nut consumers. One ounce of walnuts was added to the usual dietary intake in this modeling study. The Healthy Eating Index-2015 was used as a summary measure of diet quality. Outcomes of interest were intakes of fiber, protein, potassium, folate, magnesium, and omega 3. Nutrient intake was analyzed using the National Cancer Institute method (NCI), while the HEI-2015 score was estimated using the population ratio method. Significant differences were determined using non-overlapping 95% CIs. RESULTS: HEI-2015 scores were significantly higher in Modeled diet compared to usual diets (58.5 ± 0.5 vs. 49.1 ± 0.6) out of 100 total points. Adding walnuts increased the energy density per 1,000 calories of the total protein, seafood and plant proteins, and polyunsaturated fatty acids, thus increasing the individual component HEI scores in these areas. Compared to usual diet, modeled diet significantly improved inadequacy for magnesium (48.3% to 34.6%), folate (28.3 to 22.0%), Copper (16.2%to 0.2%), and zinc (21.1% to 14.7%). Further, mean fiber intake significantly increased from 13.6 ± 0.2 to 15.4 ± 0.2 grams. CONCLUSIONS: Public health messages targeted at no-nut consumers should emphasize the benefits of nut consumption, specifically walnuts, to improve diet quality. Further, adding walnuts to the diet improves the inadequacy of folate, magnesium, and trace minerals. Food pattern modeling using NHANES data can be used to assess nutritional impacts of compliance to current dietary guidance. FUNDING SOURCES: This study was funded by the California Walnut Commission.