Although medical treatment (for example orlistat [ Alli , Xenical ]) is available, they should only be used by people who have health risks related to being obese . Doctors usually consider medications to be an appropriate treatment in patients with a BMI greater than 30 or in those with a BMI of greater than 27 who have other medical conditions (such as high blood pressure , diabetes , high blood cholesterol ) that put them at risk for developing heart disease . It is not recommend that medications be used for cosmetic weight loss or to lose small amounts of weight.
The most common estimation of IBW is by the Devine formula; other models exist and have been noted to give similar results.  Other methods used in estimating the ideal body weight are body mass index and the Hamwi method. The IBW is not the perfect fat measurement as it does not show the fat or muscle percentage in one's body. For example, Athlete's results show that they are overweight when they are actually very fit and healthy. Machines like the dual-energy X-ray absorptiometry (DXA) can accurately measure the percentage and weight of (fat, muscle, bone) in a body.