It might vary from area to area, I guess.
When I started working in high schools in the '80s, I saw very few obese teenagers; now I see a great many. More obese girls than boys, but the boys are there.
I do also see slim teenage boys and a small number of slim teenage girls at the gym that I attend.
I'm in the process of shifting weight myself...but I was slim as a teenager. I find myself wondering what's going to happen to the teenagers who are currently obese. It's a health crisis in the making.
I'm in my 60s, but I'm seeing much larger women going around who look to be in their 30s.
I know that the local health board is trying to do something about health in the area: I was referred to the local gym after finishing my physio sessions, following a shoulder op - a "fitness for life class". My problem was muscle loss following depression after my husband died. However, merely by attending the class I lost a stone over 6 months. I've increased my protein and I'm now attending 3 to 4 gym sessions a week and I'm getting fitter though nothing will help my knees - there's a congenital condition, patella alta, which means that they're prone to locking on me. I'm 5ft 9. Another two stone and I'll be back down to my "normal" weight.
When I started, my thigh muscles had atrophied to the extent that I needed to push up with my arms to stand up. Now my thighs are strong enough to raise me while I'm holding a 5kg medicine ball and I'm doing arm raises with two 4kg weights and I'm back to using a lat press. The aim is to do better, in order to keep healthy enough to be independent.
Most of the people in my class are there following operations. There are also another couple of classes for obese people. (Some are clearly morbidly obese.) All the classes run for 12 sessions with an option to continue at the drop-in classes. The problem is that the younger obese folk are having difficulty fitting the classes into their schedule. I get the problem - I couldn't return to the gym while I was still caring for my late husband.
I do worry about obviously obese teenagers, though. Part of the problem nowadays is that when they refuse to participate in PE by "forgetting" their kit the school really can't do anything about that these days. The other problem, of course, is the amount of fast food that they eat.