There could be various causes of unexpected and unintentional weight loss. This could be:
- A symptom of a disease, for example, type 1 Diabetes, cancer, depression, hyperthyroidism (overactive thyroid), and others
- A side-effect of taking certain medications, for example, amphetamines (psychostimulants) or thyroid drugs
- A result of certain behaviors, such as smoking, drug abuse, poor sleeping habits, or certain eating disorders (bulimia, anorexia nervosa, etc.)
Not all unexplained weight loss is a reason to be concerned. However, if you lose more than 5% of your previous body weight without trying, it's smart to investigate the cause.
