People do not always take action to promote health, engaging instead in unhealthy habits and reporting fatalism about health. One important mechanism underlying these patterns involves identity-based motivation (D. Oyserman, 2007), the process by which content of social identities influences beliefs about in-group goals and strategies. Seven studies show the effect of identity-based motivation on health. Racial-ethnic minority participants view health promotion behaviors as White middle class and unhealthy behaviors as in-group defining (Studies 1 and 2). Priming race-ethnicity (and low socioeconomic status) increases health fatalism and reduces access to health knowledge (Studies 3 and 4). Perceived efficacy of health-promoting activities is undermined when racial-ethnic minority participants who identify unhealthy behavior as in-group defining are asked to consider their similarities to (middle-class) Whites (Studies 5-7).