Instant noodles, processed food intake, and dietary pattern are associated with atopic dermatitis in an adult population

Possibly due to the westernization of lifestyles and diets, the prevalence of atopic dermatitis has been growing continuously even among adults in industrialized countries, such as Korea, over the last several decades. However, the association between processed food intake including instant noodles and atopic dermatitis has not been studied in a large adult population. We investigated the association between dietary habits and atopic dermatitis in 17,497 adults by using the 2009 2011 Korean National Health and Nutrition Examination Survey (KNHANES). We identified 4 dietary patterns with the use of principal components analysis using a 63-item food frequency questionnaire: the ‘‘traditional dietary pattern’’, rich in rice and kimchi; the ‘‘meat and processed food pattern’’, with more meat, noodles, soda, and processed foods including instant noodles; the “healthy dietary pattern”, high in grains, vegetables, fruits, and seaweeds; and the “drinking dietary pattern”, mainly drinking coffee and alcohol. Adjusted odds ratios for atopic dermatitis were calculated according to dietary patterns after adjusting for potential confounders with incorporation of sample weights for the complex sample design of the survey. With respect to instant noodles, the high consumption groups showed significantly higher ORs for having atopic dermatitis, 1.57 fold higher, as compared with the low consumption group (reference group) regardless of adjustment for potential confounders. In the meat and processed food groups with and without instant noodles, the ORs for having atopic dermatitis paralleled with those of the instant noodle groups. In contrast, the groups with high intake of rice and kimchi exhibited lower ORs, which were 0.38 and 0.43 folds lower, respectively, in comparison to the groups with low intake with and without adjustment for covariates. In conclusion, the consumption of instant noodles and meat and processed foods was associated with increased prevalence of atopic dermatitis in adults, whereas the intake of rice and kimchi, and coffee was associated with decreased prevalence of atopic dermatitis.