Shouldn't there be a control group, with a task not involving food, to see if the issue is food-related, or generally with impulse control? Maybe ask them to do

Shouldn't there be a control group, with a task not involving food, to see if the issue is food-related, or generally with impulse control? Maybe ask them to do some boring task they were told was important, but have Facebook, TV,sports or some other distraction immediately available too. I suspect the same people who had trouble with controlling food intake would also have trouble with other self control or delayed gratification tasks.