A good weight loss program should include plans for weight maintenance after the weight loss phase is over. It is of little benefit to lose a large amount of weight only to regain it. Weight maintenance is the most difficult part of controlling weight and is not consistently implemented in weight-loss programs. The program you select should include help in permanently changing your dietary habits and level of physical activity, to alter a lifestyle that may have contributed to weight gain in the past. Your program should provide behavior modification help, including education in healthy eating habits and long-term plans to deal with weight problems. One of the most important factors in maintaining weight loss appears to be increasing daily physical activity, often by sensible increases in daily activity, as well as incorporating an individually tailored exercise program.
(Source: National Institute of Diabetes & Digestion & Kidney Disease)