According to research done at the USDA, eating enough protein at the end of the day is important for those who want to lose weight and maintain their muscle mass. The body needs protein throughout the night to build and repair itself, and a light evening meal may not give it enough protein to do so. So get adequate protein at every meal, including dinner.
Protein also has 30-40% more vagus nerve-stimulating ability than carbohydrates or glucose. Stimulating the vague nerve tells you to stop eating. This is why protein helps curb appetite. This is also one of the reasons it is easier to overeat starches and sugars than protein.
Crayhon, Robert. The Carnitine Miracle: the Supernutrient Program That Promotes High Energy, Fat Burning, Heart Health, Brain Wellness, and Longevity. New York: M. Evans, 1998. Print.