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Underweight
classification of human body weight / From Wikipedia, the free encyclopedia
The term underweight refers to humans that have much less weight than they should. Being underweight is bad for the overall health of the person affected. It is normal that a person's weights changes over time. Being underweight is often defined using a measure called the body mass index which calculates a score, based on height and weight. If this score is below 18.5, a person is generally said to be underweight. This is only a general indication, though as the scores must not be calculated for everyone. It does not apply to children and adolescents, for example.
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Being underweight can have different causes:
- Malnutrition, not eating enough, or eating the wrong kinds of foods. The right kinds may not be available, or they may be too expensive to buy.
- The weight of a person is also determined by genetic factors. One of these factors is that some people have a "lighter build" than others.
- Stress, anxiety and depression can influence weight.
- There are eating disorders that cause people to become underweight. The most common of these are anorexia nervosa and bulimia nervosa.
- Sudden unexplained weight loss can point to a disease, such as cancer, tuberculosis, hyperthyroidism, type 1 diabetes or inflammatory bowel disease.
- Sometimes the use of drugs leads to weight loss.
- Organs of the digestive tract may not be working as expected.
- People who train sports too much may be using more energy than they get.