ACKGROUND/AIMS:Vegetarian and vegan diets are effective in preventing and treating several chronic diseases. However, their acceptability outside a clinical trial setting has not been extensively studied. The aim of this study was to determine the acceptability of a worksite vegan nutrition program and its effects on health-related quality of life and work productivity. METHODS: Employees of a major insurance corporation with a body mass index > or =25 kg/m(2) and/or a previous diagnosis of type 2 diabetes received either weekly group instruction on a low-fat vegan diet (n = 68) or received no diet instruction (n = 45) for 22 weeks. RESULTS: The vegan group reported improvements in general health (p = 0.002), physical functioning (p = 0.001), mental health (p = 0.03), vitality (p = 0.004), and overall diet satisfaction (p < 0.001) compared with the control group. The vegan group also reported a decrease in food costs (p = 0.003), and increased difficulty finding foods when eating out (p = 0.04) compared with the control group. The vegan group reported a 40-46% decrease in health-related productivity impairments at work (p = 0.03) and in regular daily activities (p = 0.004). CONCLUSIONS: A worksite vegan nutrition program is well-accepted and can be implemented by employers to improve the health, quality of life, and work productivity of employees.