DS(10) has been fairly slim growing up, but in the last six months or so has put on a fair bit of weight, and is now slightly overweight. We eat reasonably healthy meals and I think both DH and I model a healthy attitude to food - we both enjoy good quality food and the odd treat, but within reason, and we are both healthy weights. The trouble is DS has a massive appetite right now and also a very sweet tooth, and seems to have no off switch whatsoever. For example, he was at a party the other day and announced afterwards he had eaten seven pieces of cake! This morning I emptied out his school trouser pockets and found an empty Twix wrapper AND an empty Skittles packet (both full size) which presumably he had eaten that day (we aren't in the UK and their school has a pretty relaxed shit attitude towards sweets etc so it doesn't surprise me that he has access to this stuff. At home we can police it up to a point, but increasingly he is in a position to make these choices for himself.
I'm at a loss about what to do. One the one hand I want to confront him and read him the riot act about the sweet wrappers, but I know that probably isn't helpful and he will just get better at hiding it from us. But I don't feel like we can just ignore it.
Also, he isn't in to sports and although we encourage him to be active and have family hikes, bike rides etc we live in a car dependant place and he isn't getting the exercise he should. But he isn't motivated to do more.
I'm not sure how aware he is about his weight. We talk about making healthy choices, but in a general way.
I'd be ever so grateful for any suggestions.