On July 30, 2018, the U.S. Department of Housing and Urban Development (HUD) rule prohibiting residents of public housing from smoking within twenty-five feet of any housing project took effect. These new regulations—HUD’s “smoke-free policy”—received near-universal acclaim as a means to improve public health, in particular by reducing vulnerable populations’ exposure to secondhand smoke. This Essay analyzes the smoke-free policy from the perspective of healthism—discrimination on the basis of health status. We argue that banning public housing residents from smoking is unfairly discriminatory for a variety of reasons. To start, the rule may not achieve its desired effects. Because a violation could lead to eviction, the policy may well push many public housing residents out onto the street, ironically worsening health outcomes. The rule also intrudes into the private lives of smokers in public housing by forbidding them from engaging in lawful conduct in the sanctity of their homes. It singles out smokers for regulation in a way that validates stigma. Finally, HUD’s smoke-free policy poses unappreciated distributional concerns, with the heaviest burdens falling on historically disadvantaged populations like the elderly, people with disabilities, certain racial and ethnic minorities, and the poor. The Essay concludes by attempting to salvage the rule by reflecting on how HUD might modify its policy to improve compliance and avoid discrimination, including smoking shelters, smoking cessation support, and incentive structures.