From Paul Krugman, “Inequality Is a Drag” (emphasis mine):

Consider, for example, what we know about food stamps, perennially targeted by conservatives who claim that they reduce the incentive to work. The historical evidence does indeed suggest that making food stamps available somewhat reduces work effort, especially by single mothers. But it also suggests that Americans who had access to food stamps when they were children grew up to be healthier and more productive than those who didn’t, which means that they made a bigger economic contribution. The purpose of the food stamp program was to reduce misery, but it’s a good guess that the program was also good for American economic growth.