Cachexia, the Hidden Challenge for Cancer Patients: What You Need to Know When You Are Down to Skin and Bones

Modern medicine defines severe weight loss, muscle wasting, and the resulting asthenia in cancer patients as cancer cachexia. This is a complex metabolic disorder that goes beyond simple nutritional deficiency or loss of appetite. Just as an engine overheats while a car wastes fuel, cancer cells induce abnormal metabolic activity within the body and relentlessly trigger inflammatory responses. Various cytokines and inflammatory mediators secreted by cancer cells disrupt the normal metabolic processes of our body. In particular, they activate enzymes that cause proteolysis, promote the breakdown of adipose tissue, and reduce the ability to synthesize new muscle or fat. Through this process, muscle and fat are rapidly depleted, and the function of mitochondria that produce energy also declines, accompanied by extreme fatigue. This is why patients fail to gain weight and instead lose it no matter how much they eat: the energy expended by the body far exceeds the energy taken in. Furthermore, cancer cachexia deeply affects the neuroendocrine system. It elevates levels of the stress hormone cortisol to accelerate proteolysis, and acts on neurotransmitters in the hypothalamus that regulate appetite, worsening the loss of appetite. For example, signals of leptin or pro-opiomelanocortin (POMC), which suppress appetite, are amplified, while responses of ghrelin or neuropeptide Y (NPY), which stimulate appetite, can become blunted. Due to these complex mechanisms, cancer patients lose interest in food, and even if they eat, they find themselves unable to properly absorb or utilize the nutrients. Cachexia goes beyond physical wasting; it reduces the efficacy of chemotherapy and weakens immune function, critically impairing patient quality of life and survival rates. Because a weakened body struggles to endure treatment and faces a higher risk of complications, cachexia is recognized as an issue that must be actively managed during cancer care. These warning signs from the body should never be overlooked, and careful countermeasures should be discussed with medical professionals.