This business of living longer can't go on forever. There must be a cutoff point at which we will have reached the maximum age a human can be expected to live to. Granted science will increase that number and we may even reach immortality eventually but not in my time.
I would say that lack of exercise here is more prevalent than in the countries you mention. Japan eats far more fish than us and much less dairy such as butter and cheese that have saturated fats with cholesterol. Also we are at the top of the league for alcohol consumption. Some say the Mediterranean diet is good for you , ie S France and Italy, both use more olive oil and less butter. The Dutch cycle a lot.
As a nation we eat too much - especially processed and junk foods.
We drink too much - especially the middle aged.
Just take a good look at the people on the streets - have you noticed a huge increase in the number of fat people? Look at the age grouping - you'll notice far more of them are under 40 than used to be the case, and a far greater proportion of young women are considerably overweight.
Obesity is the curse of the modern age. Well over a quarter of British people are obese, and the figure is rising - we are now the most obese nation in Western Europe. By 2050 over 50% of the population will be obese if nothing is done about the problem.
Levels of Cancers, strokes, heart attacks and diabetes are all linked to obesity, coupled with the fact that we are a lazy nation - people do not take nearly enough physical exercise.