When it comes to thinness in medicine, it is generally referred to a physical condition in which the Index of body mass (BMI) below 18.5. In particular, there is a condition of "underweight" in the case where the body mass index showing between 16 and 18.5 and of "a severe thinness" when the Body Mass Index is less than 16.

The Index Body Mass, also called Body Mass Index (BMI) according to Anglo-Saxon terminology, is currently one of the methods used to determine if an individual is normal weight, underweight, overweight or obese. It is calculated by dividing body weight in kilograms by the square of height in meters. In a person who is 1.67 meters high and weighs 60 kg BMI will therefore 21.58.

The majority of health authorities around the world agree that people with a BMI below 18.5 are underweight; severely lean if below 16; normal weight with a BMI between 18.5 and 25; overweight with a BMI between 25 and 30 and obese with a BMI greater than 30.

Not all types of thinness are equal. The thinness may in fact be of a constitutional (relative, that is, the constitution of the individual and do not have known causes origin); It may be secondary to physiological causes (increased physical activity, restricted diet) and sometimes depend on pathological causes (endocrine diseases, chronic infectious diseases, cancer, digestive disorders and mental disorders).


What kind of diseases can be associated with thinness?

The following diseases may be associated with thinness:

  • Anorexia
  • Chronic obstructive pulmonary disease (COPD)
  • Celiac disease
  • Emphysema
  • Food intolerance
  • Lactose intolerance
  • Adrenal insufficiency
  • Hyperthyroidism
  • Graves' disease – Basedow
  • Malabsorption
  • Typhus
  • Tuberculosis
  • Thyroid tumors

Remember that this is not an exhaustive list and it is highly recommended to consult your doctor, in case of symptom’s persistence.


What is the therapy for thinness?

Because the medical conditions that can be associated with thinness are many and differ in the case of not desired weight loss, particularly when abrupt and / or significant, it is always good to ask for a consultation with your doctor. Knowing the motivation behind the weight loss is in fact the first essential step to prepare a suitable remedy to the situation and his own physical condition.


When is most likely to contact your doctor in case of thinness?

In case of already diagnosed illnesses (see list of associated diseases).