Now I am in my late 50s and down to 210.
Mine was mostly trying to climb the corporate ladder and working too many hours, like most younger people do. I ate like garbage. I would stop somewhere and get breakfast (usually some place like 7-11), eat fast foot for lunch, and eat unhealthy snacks. Oh, and I was probably drinking like 2 gallons of diet coke a day.
The only healthy food I ever ate is what my wife would feed us for dinner.