Limited health literacy is a pervasive and independent risk factor for poor health outcomes. Despite decades of reports exhibiting that the healthcare system is overly complex, unneeded complexity remains commonplace and endangers the lives of patients, especially those with limited health literacy. In this article, we define health literacy and describe the empirical evidence associating health literacy and poor health outcomes. We recast the issue of poor health literacy from within the ethical perspective of the least well-off and argue that (...) poor health outcomes deriving from limited health literacy ought to be understood as a fundamental injustice of the healthcare system. We offer three proposals that attempt to rectify this injustice, including: universal precautions that presume limited health literacy for all healthcare users; expanded use of technology supported communication; and clinical incentives that account for limited health literacy. (shrink)