My dad smoked like a chimney, did little exercise and ate a diet that wasn't exactly brilliant.
He died at the age of 57, because at the end of the day, a poor diet, lack of exercise and a tobacco habit is bad for you.
People who wheel out the anecdotal "My old gran lived on chips, smoked 60 a day and lived until a hundred" are flying in the face of the fact that most people who eat crap diets and smoke a lot die younger than average.