Sometimes it isn't how much you eat but what you eat as I found out for myself recently.
I thought my diet was fairly good, but my weight was creeping up and up then one day I noticed my Son-in-law had lost some weight so I asked him how he had done it and he said, by cutting out the carbs.
So, I did that and before long I'd lost 1 1/2 stone.
Just to check that was the cause, I went back to eating bread and potatoes and slowly but surely my weight started to creep back up.
Now I've proved it to myself, I have gone back to not eating as much bread and looking at the carb content on other foods, but I do allow myself carbs at the week-end as a treat, and the weight is starting to come off again.