Depending on what your weight is and if you are already close to goal, or how much more you have to lose. You cant kick off a new diet. It will be a non stop new thing that you have to go thru unless you see it as a life style change. Diets come and go as fast as new name comes up for them.
Alot depends on whats going on , are you eating enough for the day, are you working out to much or to little, are you getting enough rest.
Are you taking in the wrong kinds of nutrtion that your
body does not need.
How many calories are you taking in.
Theres many diffrent areas that you might need to look into to. But dont let it upset you just really look at what your doing , be honest with yourself at all times and you might already know whats going on.