Overeating, compulsive easting, and especially secret eating is, indeed, self harm
And almost everyone who does it knows that, but cannot stop themselves
The nasty smug idiots replying "If he cared he'd stop" "I just gave up eating before lunch" "It's his choice" have absolutely no idea what it's like to be unable to change
My family were poor when I grew up (1960/s70s)
At least once a week, far more often two or three times, my parents didn't have dinner to make sure me and my sister could
Meat was literally a once or twice a week treat, fish was almost unheard of
All four of us now have food issues
I am obese and a solitary eater, my sister is always on some fad crash diet, my dad is anorectic (yes, it's not just women who suffer from anorexia), my mum's weight and size balloon up every three or four months, then she's a mean, spiteful person as she starves herself and fights it back down to healthy, and then once se 'relaxes', boom! Back up it goes again
This is not because we are weak willed, or selfish, or even lazy, but because for 15-20 years of our lives we did not have enough food
As Professor Jack Cohen said, "food and money and love are like oxygen, when you have enough, they are not important, when you don't have enough, they are desperately needed and thinking about them is all-consuming"
Desperation leaves mental scars that, for many people, never heal