I am facing the same problem. My husband returns to work May 1. His job is physical and outdoors. His usual method of lunch was stop at a fast food, but since double bypass surgery he is on a low salt, low fat diet. At home, it has been relatively easy. But for the lunchbox? I am looking at purchasing a cooler/heater unit for his truck. That way he can take warm foods with him without having to worry about heating them up. Has anyone used these and do they work?