While a person who is statistically underweight may still be suffering from the disorder which causes obesity, it is also possible for a person to be statistically overweight without suffering from obesity. For such persons weight is no problem, as they can gain or lose at will and experience no difficulty in reducing their caloric intake. They are masters of their weight, which the obese are not. Moreover, their excess fat shows no preference for certain typical regions of the body, as does the fat in all cases of obesity. Thus, the decision whether a borderline case is really suffering from obesity or not cannot be made merely by consulting weight tables.