I'm so unhealthy when it comes to diets, last diet I made was eating only 500 calories a day... worked great, lost 10 pounds in a month, but hey, now I got 4 of those back since it's in the end one of those diets that make you gain back the lost weight pretty quick... totally not recommended.
Indeed, doing exercise and eating healthy is the way to go if you wanna lose weight and keep the lost pounds away