When choosing what to eat, some people seem to have better will power than others. They are more likely to make decisions based on healthiness than momentary tastiness. A new study suggests that those people with greater control over what they eat also have more gray matter in certain parts of the brain. 

Learn what it means with LiveScience.com:

https://www.livescience.com/62744-gray-matter-brain-predict-diet-success.html