What does it mean to lose weight?
Weight loss, in the medical field, refers to a reduction in the total body mass; this is caused by the reduction of: fluids, fat mass (body fat and / or adipose tissue) and lean mass (ie mineral deposits in the bone, muscle, tendons and other connective tissues).
Weight loss can occur either unintentionally due to a disease or through a conscious effort to improve a real (or perceived) state of overweight / obesity.
The so-called "unexplained weight loss", that is not caused by the reduction in caloric intake compared to energy expenditure (voluntary or not), is called cachexia and can be a serious symptom of a medical nature.
Intentional weight loss is commonly identified as weight loss but, in accordance with the cited introduction, represents a totally different process from cachexia.
How to estimate weight loss in the medical field?
Unintentional weight loss can be the result of an actual weight loss (fat mass depletion), or the loss of body fluids, muscle atrophy or even a combination of these elements.
Involuntary weight loss is considered a medical problem when it occurs: at least 10% of the total mass in six months, or at least 5% in the last month.
Another medical criterion used to estimate the suitability of the total weight (in normal adult subjects, not in children and even less in athletes) is the body mass index (BMI). This involves placing the patient within one of the following categories (range representatives): underweight, normal weight and overweight. It can be seen that, within the same category, even a rather significant variation (eg 10kg) can occur. On the other hand, in certain elderly people, similar or even lower fluctuations within the normal weight can be much more worrying than interpreted by the BMI.
What are the characteristics of an involuntary weight loss?
Involuntary weight loss can occur due to a diet that is not sufficiently nutritious as a result of malnutrition.
They can also cause unintended weight loss: pathological processes, changes in metabolism, hormonal changes, drugs or other treatments, pathological changes and decreased appetite.
Intestinal malabsorption can lead to involuntary weight loss and can be caused by: fistulas, diarrhea, drug-nutrient interactions, absence or enzymatic insufficiency and mucosal atrophy.
What is cachexia?
As anticipated, the involuntary progressive and fraying weight loss is sometimes referred to as cachexia. This differs from weight loss also due to the presence of a systemic inflammatory response and is often related to poor diagnostic results.
In the advanced stages of a progressive disease, the metabolism can change leading to weight loss even through a balanced diet, without inducing an increase in the sense of hunger. This condition takes the name of: syndrome of cachexia anorexia (ACS), often impossible to cure even through integration.
Symptoms of involuntary weight loss for ACS include: severe muscle depletion, loss of appetite and early satiety, nausea, anemia, weakness and fatigue.
Involuntary weight loss is a diagnostic criterion for cancer, type 1 diabetes mellitus, thyroid problems, etc.
What effects can serious involuntary weight loss have?
Involuntary and severe weight loss can reduce the quality of life, compromise the effectiveness of a therapy or recovery, worsen the pathological phases and constitute a risk factor for the increase in the mortality rate.
The resulting malnutrition can compromise every function of the human body, from individual cells to the most complex functions of the body: immune response, wound healing, muscle strength (eg of respiratory muscles), kidney function, thermoregulation, menstrual cycle etc.
Furthermore, the associated malnutrition implies the lack of electrolytes, vitamins etc. Even the illness that often accompanies severe weight loss can lead to other complications such as, for example, bedsores.
According to UK data ( Malnutrition Universal Screening Tool - MUST), up to 5% of the general population is underweight and more than 10% of those over 65 are at risk of malnutrition.
