A person may be<unk>  due to genetics, improper metabolism of nutrients, lack of food (frequently due to poverty), drugs that affect appetite, illness (physical or mental) or the eating disorder anorexia nervosa. Being<unk>  is associated with certain medical conditions, including type 1 diabetes, hyperthyroidism, cancer, and tuberculosis. People with gastrointestinal or liver problems may be unable to absorb nutrients adequately. People with certain eating disorders can also be<unk>  due to one or more nutrient deficiencies or excessive exercise, which exacerbates nutrient deficiencies.
Underweight
Overweight
Obesity
Gestational age
Infant formula
Human height
Human body weight
Multiple birth