Many breast cancer patients (BCP) will gain weight during chemotherapy and about 10% of them are able to find back to their initial weight after all treatments are finished. Other studies have shown that overweight at diagnosis was associated to a twice higher risk of relapse while a weight gain during treatments increased by 30% to 50% the risk of relapse. In western countries, 75% of BCP have insufficient physical activity. Dietary and activity programs seem to be able to significantly reduce the mortality risk after breast cancer.