Weighing less than is normal, healthy or required.
Causes and risk factors:
In the west obesity is most common, whereas in the tropics underweight is more prominent due to poverty or lack of dietetic knowledge. Underweight may be due to constitutional (Familial), reduced intake, reduced absorption or due to increased utilisation of nutrients. A under-weight person is more liable to infectious diseases like tuberculosis and can belong to the high morbidity risk group.
Underweight can be due to any chronic illness like tuberculosis, asthma, cancer, immune deficiency syndrome, anaemia, some type of diabetes, etc. It can also occur in nervous, active, tensed and overworked people. In conditions like hyperthyroidism and chronic fever, underweight may be due to increased utilisation of the nutrient. In conditions like chronic bleeding, of any cause, result in loss of nutrients leading to underweight.
Eating is the first and most important factor that is needed for proper weight gain – put simply, you need to eat more calories than you burn. Taking meals and snacks more frequently will help accomplish this. Eat every 2.5 to 3 hours; focus on foods higher in protein along with fruit, vegetables and assorted types of nuts. What you eat is the most important ingredient in a successful weight gain program.