OBJECTIVES: The Impact of Weight on Quality of Life-Lite (IWQOL-Lite) has been widely used in obesity research. More recently, the IWQOL-Lite has been used in studies in Type 2 diabetes.  We were interested in understanding if the IWQOL-Lite was acceptable in Japanese type 2 diabetes patients because average body mass index (BMI) is lower in Japanese than in Western subjects.     METHODS:  Subjects (10) with clinically confirmed type 2 diabetes were recruited in Tokyo for cognitive debriefing of the Japanese version of the IWQOL-Lite. Subject responses were compared to responses from the original translation interviews for obese patients.  RESULTS:  Type 2 diabetes patients did not endorse all of the items in the IWQOL-Lite. Due to some of the comments provided, responses were compared to the obese population studied during the original translation. Several cultural issues were noted. First, Japanese subjects are not as heavy as Western subjects, so the questionnaire appeared less relevant to diabetes subjects. In addition, the question “trouble tying my shoes” was seen as not relevant, in part due to being less heavy and in part because many Japanese do not tie their shoes on a regular basis. Also, the Japanese subjects did not like the term “because of my weight” and preferred “because I am fat”. This feedback was provided in the original interviews as well. In this sample of subjects with type 2 diabetes, public distress, self esteem and sexual life were not seen as important but were more relevant to the obese population. CONCLUSIONS: Issues can occur when a questionnaire is adapted to a new language as well as using it in a different population. Thus based upon our small cognitive debriefing study, the IWQOL-Lite as currently developed and translated does not appear to be relevant for patients with type 2 diabetes in Japan.