Diabetes is known to cause workforce exit after complications develop, yet little research has examined the effects of the disease and its treatment on work efficiency while diabetics are employed. OBJECTIVE: The goal of this research is to determine whether or not diabetes is associated with lower levels of work productivity. METHODS: To measure work productivity, a survey was designed to collect data on work efficiency, as defined by Osterhaus, et al. and van Roijen, et al. The survey also included items about absences, work history, workforce exit, job satisfaction, income, demographics and health care utilization. The survey was administered to diabetic and non-diabetic people who were employed. RESULTS: On average, the 72 diabetics who completed the survey reported significantly lower work productivity than their 362 non-diabetic co-workers. Diabetics averaged the equivalent of seven hours of lost work time per month while non-diabetics lost only four hours per month (p = 0.03). Surprisingly, the cost of these productivity losses was not significantly different between diabetics and non-diabetics. This is because the diabetics reported incomes that averaged $10,000 less per year than their non-diabetic co-workers (p <0.02). CONCLUSIONS: Diabetics appear to be less productive at work than their non-diabetic peers, on average. The cost of lower productivity appears to be borne, at least in part, by the workers themselves, who earn significantly less than their non-diabetic co-workers, on average. Given the rising prevalence of diabetes and variations in treatment patterns, the effects of diabetes teatments on work productivity and career progression deserves consideration.