MikeS - re your post earlier...
I am of a similar generation to you and I too remember the chip pan. Although the chips were home made and thicker, containing less fat, than the French Fries lots of kids eat now. On the days we did not have chips we tended to have a stew based on the fresh veg my Dad brought home from his friends at the market. The stew was based on a stock cube, not thick creamy sauces.
Although sweets were readily available in my home these were treats and not part of the staple diet kids of today seem to have. Again, our treats were brought home from the market in the way of an orange.
Re. the `smuts'. I guess if people were brought up in an industrial area then this might be the case (although I am told that the industrial area of Hull smelt of fish, not smoke
) but for me, brought up in the Welsh valleys, the rolling hills were my playground, with no fresher air than that
Generally there are lots of fair points being made here, but my general impression (not empirical evidence) is that the lifestyle 30 years ago was more conducive to producing fitter people than it is now.
As a contrast, when I was bringing up my kids in the 1990s, with a higher disposable income and me out at work (unlike my mother) meals were sometimes fast food, sport was seen as being less competitive and more of a pastime in schools and although both my sons have played sport to a professional level, I am sure that had they turned to running rather than football, they would have been disadvantaged by the `easy' lifestyle I could provide at that time compared to my childhood. They got driven to school and to football practices whereas when I raced XC at school I would walk home afterwards.
Therefore I feel that a bit of all these factors come into play, and it is just where you choose to place the emphasis.