I think there are many factors. Portion size being one of them,we went out for fish and chips as a family last month and were shocked at the portion sizes, they were huge needless to say we wasted such a lot of the meal but just could not eat that vast amount. Children used to play outside a lot,but many of them play computer games while eating snacks ,unfortunately if they don’t excercise they will pile on the weight. Parents would need to take the lead and show the children that they can enjoy the nice things in moderation,and also teach them that excercise will keep them fit and healthier in later life. I hope it happens soon, as the young people of today will have a miserable middle age if they end up with illness due to the weight problems starting while they are young, and they may never reach old age.