One of the most mentioned processes is the metabolism alteration. When key organs like the liver or the kidneys they decrease their ability to filter and eliminate toxins, certain substances begin to accumulate in the body. Part of these compounds can be released through breath, the fur or the body fluids, generating unusual aromas. Some people describe them as sweet, metallic or simply different from the usual smells of the human body.
Changes in the blood circulation, common in patients with serious illnesses or in states of great weakness. When blood flow to the skin and extremities is reduced, variations in blood flow occur temperature, the humidity and the skin chemistry. These conditions can favor the appearance of more intense odors, especially if the person remains in prolonged rest or with very limited mobility.