When eating out, helpful tricks like sharing an entree or ordering an appetizer instead of a main dish can curb calories. But your choice of dining companions may factor into the equation, too.
An experiment done at the Cornell University Food and Brand Lab confirmed the theory that people are less likely to stick to their own diet rules when eating with or near someone overweight. The researchers found that diners at a buffet ate larger portions of unhealthy foods—and smaller portions of healthy foods—even when the overweight person ate less.
One possible explanation for this behavior is that people become less in tune with their goals when they see others who are overweight.