Why dining with friends makes you eat less: You're less interested in the food on your plate

Daily Mail - Science & tech 

If you are trying to lose weight, inviting friends round for a dinner party might be a good idea. Dining with other people could make someone eat less, a scientific study suggests. That is because the same part of the brain involved in social engagement also controls food cravings. A study tested this theory in mice, whose brains work in a similar way to those of humans. When scientists stimulated their social brain cells the animals were less interested in consuming a high-calorie treat.