DS(14) is overweight. He has an extremely sweet tooth, a penchant for carbs and spends a lot of time online gaming. He walks to school and does do a physical activity a couple of times a week (which we have to encourage), but not enough to offset the fact he is eating too much of the wrong things and is very sedentary.
For background, DH and I have never struggled with our weight. We eat healthily but not obsessively so. So DS hasn't grown up being exposed to to problem eating, at least not at home. His younger siblings are very slim.
DS has recently started eating secretly, and eating large quantities of food in a single sitting. I think he is heading in to the territory of disordered eating.
As yet, I have never spoken to him explicitly about his weight, although I have told him when I think he is making poor choices e.g. buying a massive sharing-sized bag of sweets and eating them himself in a single day (this happens regularly - as an occasional one off I wouldn't make a big deal of it). This obviously hasn't helped because he is still doing it.
I think he is unhappy about his eating/weight (and possibly in general, sadly) and I feel I need to talk to him about it, but I am very, very wary about how to approach it because I know it is such an emotionally charged subject and if I fuck it up I could make things worse. I want to support him and give him the confidence and encouragement to make changes, but I have no idea where to start.
If you recognise something of yourself in my DS, what could your parents have done to help do you think? And what should I absolutely not do?
(just to note, as he has younger siblings it is difficult to completely remove temptation from the house).