Prentice et al. predicted that the emerging molecular genetics field would ultimately provide a way to test between the adaptive 'thrifty gene' idea and the non-adaptive 'drifty gene' idea because it would be possible to find signatures of positive selection in the human genome, at genes that are linked to both obesity and type 2 diabetes, if the 'thrifty gene' hypothesis is correct. Two comprehensive studies have been performed seeking such signatures of selection. Ayub et al. (2014) searched for signatures of positive selection at 65 genes linked to type 2 diabetes, and Wang and Speakman (2016) searched for signatures of selection at 115 genes linked to obesity. In both cases there was no evidence for such selection signatures at a higher rate than in random genes selected for matched GC content and recombination rate. These two papers provide strong evidence against the thrifty gene idea, and indeed against any adaptive explanation which relies on selection during our recent evolutionary history, but rather provide strong support the 'drifty gene' interpretation.