Effect of Food Sensitivity on Overweight Assessed Using Food-Specific Serum Immunoglobulin G Levels

Abstract

Food sensitivity is considered to be implicated in obesity via chronic inflammation. Obesity has become a global epidemic, and overweight is a gateway to obesity. Hence, understanding the effect of food sensitivity on overweight is important for public health. To examine the association between food sensitivity and overweight, we compared the levels of diverse serological IgGs (total IgG, food-specific IgG [sIgG], and total food-sIgG [the sum of food-sIgG]) between overweight and lean Korean adults. A total of 164 Koreans aged 19-29 years participated in the study. We collected serum samples, information on frequency of food consumption, and height and weight measures to calculate body mass index (BMI). Immunoassays were performed using protein microarrays to determine total IgG, food-sIgG for each of the 68 food antigens, and the total food-sIgG. Participants were classified as overweight (BMI >= 25 kg/m(2)) or lean (BMI < 25 kg/m(2)). The Wilcoxon rank-sum test was used to compare the decile scores of IgG values between the groups. The total IgG (P = 0.58) and total food-sIgG scores (P = 0.27) did not differ significantly between the groups, precluding chronic inflammation as the cause of overweight. However, in the overweight group, food-sIgG scores against dairy products and seafood were significantly higher (P < 0.05), whereas those against fruit and vegetables were significantly lower (P < 0.05). In overweight individuals, food-sIgG scores against milk were not associated with the actual consumption (P = 0.76), suggesting higher food-sIgG as an indicator of higher sensitivity than of higher consumption. Higher sensitivity to dairy foods and seafood and lower sensitivity to fruit and vegetables are likely associated with weight gain. Future studies are warranted to understand the heterogeneous associations between food-sIgGs and overweight.