The cancer cachexia syndrome is common. Significant weight loss occurs in approximately 50% of oncology patients, with even higher values in those with gastrointestinal tumours.¹ In pancreatic cancer, approximately 80% of patients will become severely malnourished. The development of cachexia is not only distressing for patients and their families, it is also associated with a much worse clinical outcome. Malnourished patients undergoing surgery for cancer have morbidity and mortality rates of three to four times those of their better nourished counterparts,² and wasted weakened patients also tolerate chemoradiation poorly. Ultimately, malnutrition itself can be considered to be the final cause of death in approximately 30% of cancer patients. It occurs once patients have lost about one third of their premorbid body weight.

Historical explanations for the causes of cancer induced wasting have been varied. Some experts have claimed that the dominant cause of weight loss is heightened energy demands, attributable to both the needs for tumour growth and tumour triggered changes in metabolism of tissues distant to the malignant process. However, although studies confirm that the resting metabolism of cancer patients is often elevated,³total energy requirements are frequently lower than normal as patients who feel unwell do little physical activity.⁴ Furthermore, as cancer patients lose weight, their metabolic requirements fall further still. This type of …