Some people think they eat healthily and can't understand why they either put on weight or can't lose any. "Secret Eaters" delves into the science and psychology of eating by monitoring the eating habits of overweight families via 24-hour camera surveillance. With cameras installed in their shopping trolley, car, fridge and cupboards, every family member's move and mouthful is captured, and their diets are then analysed by a food science expert and a dietician. Once the families are aware of the true scale of their overeating, they embark on a 10-week `Food Rehab' regime to help them shift the pounds.