How is one motivated to change one's behaviors ... especially if the change requires physical and/or emotional discomfort or inconvenience; if it is expensive or difficult to achieve; if the person has no desire to change or doubts s/he has the ability to do what's necessary; if there are incentives or other competing forces not to change; etc.? When it comes to one's health, I believe this question applies not only to dieting, but is relevant to any preventive measures and plans of care, i.e., it's the thorny adherence/compliance problem raising its ugly head.

Information alone is typically not enough. Sure, people must know how to change and that requires good, understandable, readily available information. They also need ongoing feedback, i.e., information that enables them to know how well they're doing and what adjustments they can make to promote their progress.

But all the information in the world won't foster change unless people are motivated to make the changes.I suggest that the greatest human motivator is emotion--both positive/pleasurable emotions (love, joy, satisfaction, peace of mind, etc.) and negative/painful emotions (anxiety/fear, disgust, sadness/depression, shame, guilt, etc.). So, when people feel good about changing certain behaviors and feel badly when not making those changes, motivation is maximized and change is most likely to occur. Well, what has to happen for someone to have (or not to have) such motivating emotions? I suggest that our beliefs and values about ourselves, others, the world, the future, life-purpose, etc. are the primary triggers of these emotions. These beliefs are affected by our experiences, social surroundings, culture, religions, formal education, economic status, life opportunities, etc. Emotions are also influence by our physical condition and stress, and can be affected by certain medications, what we eat, and environmental factors.

As such, this is a very complex question, whose answer lies in a lifetime of complex mind-body-environment interactions.

It may be that comprehensive biopsychosocial assessments can help us to understand what's affecting a person's motivation to change and to help us address these influences through some type of focused counseling and personalized social (peer/family) support. Rewards and punishments, may also be useful, as long as the negative underlying psychological/emotional issues are addressed and resolved. And finally, making the change process as simple, safe and affordable as possible would help.

But we have to accept that there's no way to motivate everyone to change, nor does everyone have the physical ability to make certain changes. I'm not an expert about this, but it may be, for example, that the bodily mechanisms (e.g, metabolism) of some folks may make behavioral change (e.g., dieting) largely ineffective even if the person is motivated. Should we expect these people to undergo gastric bypass surgery?