Are you sure it's just western food, though? Here in Korea, there are plenty of unhealthy foods and drinks to consume but it's just that people are consuming more and moving less overall. They blame western food due to confusing correlation and causation, because I assure you 550 calories of ramyeon washed down by 130 calories of sugary rice drink isn't doing you any favors when you're just sitting down and gaming, reaching for more snacks.