Obesity has received increased attention arising from its increasing prevalence and the implications of obesity-related problems for society and the wider economy. To estimate healthcare and non-healthcare obesity impacts, many studies rely on body mass index (BMI) as a measure of obesity. However BMI is considered to be a noisy measure of total body fat that unlike some other measures does not capture fat distribution. This study uses one such measure, the waist-to-hip ratio, as both an alternative and in conjunction with BMI in the estimation of the relationship between adiposity and health service use. The article uses data from a large-scale study of older adults living in Ireland (the Tilda data set). The findings indicate that studies that include both measures of general and central adiposity may provide a more comprehensive characterisation of the relationship between healthcare service use and adiposity.