Other common reasons have their roots in the emotions. Some people eat constantly because they are bored, and eating is something pleasant to do. Others because they are lonely, or feel unloved, or suffer from discontent about money, job, family relationships, or social standing. People who overeat for such reasons usually find it necessary to do something about their emotional problems before they are able to tackle their eating habits successfully. _How to Lose Weight_ Physical condition, degree of overweight, and individual living habits must all be carefully evaluated before an effective, safe reducing plan can be worked out. No one can do all this for himself. Only a physician has the necessary skill and equipment to decide how much, how fast, and with what treatment a person should lose weight. What benefits one may harm another. Therefore, a reducing program should be undertaken only under medical supervision. Anyone who really wants to get rid of excess poundage can do it. Lots of people have, with determination and persistence. Desire and will power are “musts” in any reducing program. Everyone knows that self-denial is not easy and that changing long-established habits taxes the strongest will. Therefore, a person who is trying to do this difficult job deserves the help and support of his family and friends. Few people are able to persist in any course of action in the face of commiseration, indifference, ridicule, or opposition from those they love and respect. To be worth anything, a loss of weight must be permanent. Therefore, anyone who wants to benefit from a weight-reduction program must make up his mind that he is changing his eating habits for life. Going back to old patterns will only pile up the pounds all over again. Unless this fact is accepted, reducing efforts will probably be wasted. _The Body’s Need for Food_ Awake or asleep, the body needs energy for every breath, every heartbeat, every activity of living. Food supplies this energy which is measured in units called calories. When a person eats only enough to supply the energy he uses, his weight stays the same. If he takes in more calories than he needs, the excess is stored as fat. If his food adds up to fewer calories than he needs, his body takes the extra energy out of its storehouse of fat, and a loss in weight occurs. Reducing diets are based on this simple principle: _taking in fewer calories than needed to force the body to use its stored fat_.