Do you really have to be overweight to be on a diet?

No.: People go on diets for different reasons. Most want to lose weight. Some feel that they may get more energy or feel better by being on a special diet. If your normal diet is full of saturated fats, sugary items and processed foods (and you aren't overweight), then i would say a different (and healthier) diet would be appropriate and even encouraged!

Diet: A diet is just a plan for eating, it doesn't have to be a weight loss diet. The best documented diet is probably the mediterranean diet.

Diet is way: Of eating by establishing rules...Sometimes this got weight loss other times for good health in general.