People can become underweight if they do not consume enough calories from food and drinks. People can become underweight if they exercise too much and burn off too many calories. Eating disorders, such as anorexia nervosa and bulimia, can cause people to become severely underweight and lead to serious medical complications. Untreated low weight individuals can develop malnutrition, dehydration, ulcers, diabetes, anemia, kidney failure, heart disease, electrolyte imbalances, liver failure, pancreatic failure, low blood pressure, and death. People with anorexia have an increased risk for suicide.
People can become overweight if they consume more calories from food and drinks than they burn off through exercise and activity. A calorie is a unit of measure for energy. Your body needs a baseline daily amount of calories to use for energy. However, when people eat too much or make unhealthy food choices, they can consume more many calories than their bodies need. If they fail to get enough activity to burn off the extra calories, the excess calories add up to extra pounds.
People that binge eat or compulsively overeat are at risk for severe health concerns. If untreated, overweight or obese individuals are at risk for developing high blood pressure, diabetes, high cholesterol, heart disease, stroke, bone conditions, and depression. The cumulative consequences of overeating can lead to death.