We were designed by nature for a way of living and a way of eating that has almost disappeared from our culture. As a consequence we have an epidemic of chronic degenerative diseases in the Western countries.

Two out of three people are overweight or obese, one in three have a metabolic syndrome or a diabetes, one in two will come down with cancer in their lifetime or will experience diminished brain power as they age.

Understanding the biological system that regulates hunger and satiety along with energy balance is the key to preventing eating disorders, metabolic decline, muscle waste and undesirable weight gain. Observational and some randomized trials indicate that modest weight reduction (>5% of body weight) reduces the incidence and progression of many of these diseases.

Although weight control is beneficial, the problem of poor compliance in weight loss programmes is well known. Even when reduced weights are maintained, many of the benefits achieved during weight loss, including improvements in insulin sensitivity, may be attenuated because of noncompliance or adaptation. Sustainable and effective energy restriction strategies are thus required.

One possible approach may be intermittent energy restriction (IER), with short spells of severe restriction between longer periods of habitual energy intake. For some subjects, such an approach may be easier to follow than a daily or continuous energy restriction (CER) and may overcome adaption to the weightreduced state by repeated rapid improvements in metabolic control with each spell of energy restriction. The same is true with meal frequency reduction (MFR).

As the mechanisms of feeding and energy homeostasis are studied and clarified, treatments based on natural manipulation of hunger and satiety have demonstrated to be absolutely effective in the treatment of these disorders. As a matter of fact, manipulation of hunger and satiety may be useful in resetting the neurobiology of dopamine pathways, restoring hormonal activity, and attenuating or even preventing the age-related decline of growth hormone and sexual hormones.

These strategies may help affect the enormous morbidity associated with obesity and its related diseases and may also help eliminate the risks associated with drug therapy. Teaching people to experiment, to control and to manipulate hunger should become a routine preventive-medicine strategy for all the people who live in the Western countries and for all the patients who suffer from related diseases.