MOST people consider themselves above average, something psychologists call illusory superiority and, less formally, the Lake Wobegon effect, a reference to the fictional town of Garrison Keillor’s radio monologues, where he says “all the children are above average.”

Among Americans, for example, 88 percent consider themselves above-average drivers, according to one widely cited study, while 94 percent of professors believe they are above-average teachers, according to another. That unwillingness to identify as below the median is at the heart of a new advertising campaign, “Beat average,” by GNC, the supplement and vitamin retailer.

In one new commercial, a woman in her workplace’s kitchen is tempted by a box of doughnut holes and eats just one, then walks through her office. A line of doughnut holes follows her, like ducklings. “Average,” says a voice-over. “It’s out there convincing you one doughnut hole couldn’t possibly lead to another.”

Other spots depict slacking on fitness, like a man walking slowly on a treadmill that has a control panel with “saunter,” “stroll,” “loiter” and “mosey” as the pace settings. (Voice-over: “Average sets the treadmill on ‘mosey.’ ”) In another, a man rides up a short escalator, which stops, and instead of taking a few steps to the top he remains in place and nods hello to co-workers passing on the stairs. “Average isn’t a big fan of stairs,” the voice-over says.