I'm not trying to claim that people can't change their lifestyles with sustained effort. I'm really going for two things here:
1) Willpower is something for an individual to try, but given that so many people seem to completely fail at it, it's not a productive avenue for solving this problem in a systemic way. For the same reason, we e.g. prefer to design safe electrical systems instead of just telling people to be careful.
2) A lot of signals coming from our bodies influence our behavior on the level beyond conscious control. It would be much easier to will yourself into healthy weight if you only had to decide to eat less, instead of constantly fighting hunger, fatigue, stress, and compulsive thoughts about food. The degree and type of such subconscious influence seems to differ between people.
1) Willpower is something for an individual to try, but given that so many people seem to completely fail at it, it's not a productive avenue for solving this problem in a systemic way. For the same reason, we e.g. prefer to design safe electrical systems instead of just telling people to be careful.
2) A lot of signals coming from our bodies influence our behavior on the level beyond conscious control. It would be much easier to will yourself into healthy weight if you only had to decide to eat less, instead of constantly fighting hunger, fatigue, stress, and compulsive thoughts about food. The degree and type of such subconscious influence seems to differ between people.