An article published in Perspectives on Psychological Science, a journal of the Association for Psychological Science, reviews the research and suggests that feeling young can actually make you look young—and have the health of a younger person, too. Harvard psychological scientist Ellen Langer has been studying how the mind influences the body for over three decades. In one classic study, she had old men live in a retreat that was retrofitted to look like it was 20 years earlier, while they pretended that they were living in that year. “Their minds were in the past. Their vision improved, their strength improved, and so on,” she says.