Question

Why does it happen that when one thinks not to to eat and resist oneselves, one succeeds to some extent but when that person starts to eat, the person goes on to eat recklessly???

Answer 1

Its better that if you dont want to eat something then dont keep it near you.
That can be because you like that thing

Answer 2

All the efforts taken by the person to keep himself away from the junk food will go in vain. Therefore you should have some junk every week on only one decided day and do some extra exercise on that particular day.