[ABSTRACT] A large percentage of the world population suffers from obesity. Between 6 and 26% of the adult Spanish population (Seedo, 1997) is obese, and up to 55% of the USA population would suffer from either obesity or overweight. Obesity increases the risk of developing several diseases such as cardiovascular disorders, diabetes and hypertension, and constitutes not only a medical problem but a social one as well. In fact, it is often associated to high levels of anxiety and depression.