Life has changed , more Labour saving devices, less physical jobs and a sedentary, stressful job is bad for your health, people used to walk more, less fancy foods, less takeaways, only had fish and chips, more people had home cooked healthy meals before ready meals made a huge impact from the 70s onward, endless ads for fast food, alcohol, drinks in general, when I was a teenager there were so many ads on tv saying don’t smoke, and showing green cross code and stuff like that, then it seemed to stop, just like the ads explaining about septicaemia, or blood poisoning, now called sepsis, and the symptoms of meningitis, those stopped too and now no one seems to know what it is, all these things contribute, of course everyone, in an ideal world, would eat right and exercise , but it isn’t an ideal world and is getting worse, asthma and other conditions are affecting more and more children and antivaxxers have caused so many to be scared of vaccinating children that diseases like whooping cough are making a come back