Background: Every person who seeks health care should be affirmed, respected, understood, and not judged. However, trans and gender diverse people have experienced significant marginalization and discrimination in health care settings. Health professionals are generally not adequately prepared by current curricula to provide appropriate healthcare to trans and gender diverse people. This strongly implies that health care students would benefit from curricula which facilitate learning about gender-affirming health care. Main body: Trans and gender diverse people have been pathologized by the medical profession, through classifications of mental illness in the Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Classification of Disease (ICD). Although this is changing in the new ICD-11, tension remains between depathologization discourses and access to gender-affirming health care. Trans and gender diverse people experience significant health disparities and an increased burden of disease, specifically in the areas of mental health, Human Immunodeficiency Virus, violence and victimisation. Many of these health disparities originate from discrimination and systemic biases that decrease access to care, as well as from health professional ignorance. This paper will outline gaps in health science curricula that have been described in different contexts, and specific educational interventions that have attempted to improve awareness, knowledge and skills related to genderaffirming health care. The education of primary care providers is critical, as in much of the world, specialist services for gender-affirming health care are not widely available. The ethics of the gatekeeping model, where service providers decide who can access care, will be discussed and contrasted with the informed-consent model that upholds autonomy by empowering patients to make their own health care decisions. Conclusion: There is an ethical imperative for health professionals to reduce health care disparities of trans and gender diverse people and practice within the health care values of social justice and cultural humility. As health science educators, we have an ethical duty to include gender-affirming health in health science curricula in order to prevent harm to the trans and gender diverse patients that our students will provide care for in the future.