Advances in genomic technologies are rapidly leading to new understandings of the roles that genetic variations play in obesity. Increasing public dissemination of information regarding the role of genetics in obesity could have beneficial, harmful, or neutral effects on the stigmatization of obese individuals. This study used an online survey and experimental design to examine the impact of genetic versus non-genetic information on obesity stigma among self-perceived non-overweight individuals. Participants (n = 396) were randomly assigned to read either genetic, non-genetic (environment), or gene-environment interaction obesity causal information. A total of 48% of participants were female; mean age was 42.7 years (range = 18-86 years); 75% were white; 45.2% had an annual household income of less than $40,000; mean BMI was 23.4 kg/m(2). Obesity stigma was measured using the Fat Phobia Scale - short form (FPS-S). After reading the experimental information, participants in the genetic and gene-environment conditions were more likely to believe that genetics increase obesity risk than participants in the non-genetic condition (both P < 0.05), but did not differ on obesity stigma. Obesity stigma was higher among whites and Asians than Hispanics and African Americans (P = 0.029), and associated with low self-esteem (P = 0.036). Obesity stigma was also negatively associated with holding 'germ or virus' (P = 0.033) and 'overwork' (P = 0.016) causal beliefs about obesity, and positively associated with 'diet or eating habits' (P = 0.001) and 'lack of exercise' (P = 0.004) causal beliefs. Dissemination of brief information about the role of genetics in obesity may have neither a beneficial nor a harmful impact on obesity stigmatization compared with non-genetic information among self-perceived non-overweight individuals.