Self Control

Mental Attitude: Attention & Self-Control.
You're trying to decide what to eat for dinner. Should it be the chicken and broccoli or the super-sized fast-food burger? Making that choice is a complex neurological exercise that can be influenced by a simple shifting of attention toward the healthy side of life. When you decide what to eat, not only does your brain need to figure out how it feels about a food's taste versus its health benefits versus its size or even its packaging, but it needs to decide the importance of each of those attributes relative to the others... and it needs to do all of this more-or-less instantaneously. When thinking about healthiness, people were less likely to eat unhealthy foods, whether or not they deemed them to be tasty, and more likely to eat healthy-untasty foods. Being asked to think about healthiness led subjects to say "no" to foods more often than they did when asked to make decisions naturally.
Journal of Neuroscience, July 2011