Define the term Underweight?

Just as overweight is the result of a positive energy balance irrespective of the etiology, underweight results when the energy balance is negative. Failure to consume sufficient calories to meet the energy requirement of the body for whatever reasons is responsible for not maintaining optimum weight. You have learnt that too much deviation on either side from the appropriate body weight increases the risk of health problems. In addition, it is relevant to note that as per the report of WHO (19981, an estimated 50 million adult women are classified as being severely underweight in developing countries. It also states that the consequences of poor health in childhood and adolescence including malnutrition become apparent in adulthood, particularly during the childbearing years.