There are a number of factors involved in the phenomenon of weight regain. These include:

• Physiological factors e.g. the decrease in metabolic rate that occurs with weight loss
• The continued availability of tempting high-calorie foods
• The challenge of maintaining a high level of physical activity

There is also a loss of one of the most powerful reinforcers that is present during the weight loss phase of treatment, namely weight loss itself. All these factors can lead to feelings of frustration and discouragement, which can in turn lead to abandoning efforts of weight control.