Facebook’s Mark Zuckerberg recently revealed that he wears a gray T-shirt every day for the same reason that President Obama limits his wardrobe to dark gray or blue suits. The fashion choices of these leaders, or rather their lack of choices, is driven by research conducted by the Carlson School of Management’s Kathleen Vohs

Vohs, the Land O’Lakes Chair in Marketing at the University of Minnesota, has discovered that making everyday choices depletes our energy and affects our ability to make important decisions.