How the presence of other people increases the amount eaten in meals was investigated by studying the impact of different companions on the spontaneous intake of free-living humans. 515 adults were paid to maintain 7-day diaries of everything they ate or drank, the time of occurrence, self-rated hunger, anxiety, and elation, the number of other people present, and their gender and relationship to the subject. Meals eaten with other people were larger and longer in duration compared to meals eaten alone regardless of the relationship of the eating companion to the subject. However, relative to other companions, meals eaten with spouse and family were larger and eaten faster, while meals eaten with friends were larger and of longer duration. This was independent of the time of day with similar effects occurring with morning, noontime, and evening meals. In addition males produced greater social facilitation of intake in females but not in males. These results suggest that the presence of other people at a meal increases intake by extending the time spent at the meal, probably as a result of social interaction, and that family and friends have an even larger effect, probably by producing relaxation and a consequent disinhibition of restraint on intake.