Any significant weight loss that a previously healthy person generally has not sought deliberately to indicate the existence of systemic disease. Therefore, if the questioning takes place clinician should ask about weight changes as a loss of 5% of body weight over a period of six to 12 months requires the immediate execution of further studies.
Physiological regulation of weight
The normal individual maintains its body weight in a predetermined level of stability quite remarkable, given how much they vary daily calorie intake and activity level. Given the physiological importance conserve energy reserves is difficult to lose weight and keep it off voluntarily.
