Hi Sara,
It's true that "Diet" is nothing more than what you eat, How you eat, how often you eat, and when you eat.
Diets Plans and Programs are out there but not a wise thing for people to do on and off again. That kind of thing messes with a persons metabolism. It tells you body to slow down and reserve and store food for later use. That's where body weight around the middle and hips and thighs comes into play.
The ideal thing and most healthy thing to do is change your eating habits to what is healthy, never over eating or under eating. Have an exercise program to help maintain the heart rate and burning of unneeded food so your body doesn't store it up. Never skip meals and alway drink your 8 glasses of water a day.
If you do the Diet yoyo your body will change how it burns weight off and how long it takes to get it off and how long it takes for it to come back on . It will come back on faster and will be more amount than lost usually, because your teaching your body not to trust you to feed it again so it become good at storing for another time.
Smiles,
Peggiann