"She hasn't had her growth spurt yet"... Then please, please leave her in peace. IF she is carrying extra weight now, it is probably in preparation for this.
It is soooo easy to make young people self-conscious about their weight. This happened to my 12yo last winter when he put on a few extra pounds... Then in February he grew 8cm in 4 weeks and is now slim... But he still believes he is 'chubby' and restricts his food consumption, in a way that is beginning to worry me... :(
My father used to comment constantly on my weight and food consumption when I was a child and teenager. My portion sizes were limited, I wasn't allowed to eat between meals and I was only allowed sweets on Saturdays. I was hungry often. School days weren't so bad, because of school dinners, but holidays could be tough.
I became a 'food sneaker'. Once, aged about 7 or 8, I cut my finger pinching a slice of bread I wouldn't have been allowed, and then couldn't ask for help dealing with the blood and pain, because I knew I'd be in trouble (I still have the scar)... If I could get away with it, I took food from other people's portions, because expected to be hungry again soon... I started stealing money for sweets and snacks... I developed the habit of 'hiding' food or sweets in my pocket and smuggling bits into my mouth secretly so that no-one would see. Even as an adult, I still find myself doing this occasionally :(
I grew up believing I was a fat child, but when I look back at photos, I can see I was not. I am, however, an overweight adult, who eats too much, and eats 'secretly', though there is no longer anyone to keep secrets from
.
Now I am grown-up, I can see my father had food issues of his own (and alcohol ones too)... Now I have children of my own, I know how ravenously hungry they can be. My kids can and do eat a full tea, then come back for a bowl of cereal, then another, then maybe toast... My 17 yo often also makes a pizza or a ready meal at midnight.
Neither of them has any surplus fat. I strongly believe kids should be able to eat whenever they are hungry.
If your daughter is eating when she is bored, then address this, and help her to deal with her boredom, rather than her eating. Exercise is one thing she could do, but there will be many other things too... Try to make sure she is too busy to eat unless she is ravenous!