Definitions for the culturally trendy "clean" eating phenomenon vary: whereas some characterize it as natural and healthy, others adopt more restrictive, moralizing, and affectively-laden definitions that may reflect disordered eating. We examined levels of familiarity with "clean" eating, sources of information, and perceptions of this dietary trend among a large, diverse sample of U.S. adolescents and emerging adults recruited from the National MyVoice Text Message Cohort ( = 1266; ages 14-24 years). Participants answered five questions assessing knowledge of "clean" eating, definitions, perceived healthiness vs. harm, and willingness to adopt "clean" eating, and responses were coded by three trained researchers. Results indicate that 55% of respondents had previously heard of "clean" eating, most commonly through social media, other online sources, and peers. Definitions were heterogeneous, with 40% offering "non-processed" or "whole foods" and 13% noting "non-GMO" or "organic" components. Few respondents (0.6%) expressed outright skepticism about "clean" eating, but many (30%) identified dietary avoidance and restriction as part of the definition. Overall, 71% characterized "clean" eating as a healthy approach, whereas 6% flagged it as "unhealthy", and 18% noted elements of both healthfulness and harm. Notably, 41% reported they "probably would" try "clean" eating themselves, with greater willingness to try "clean" eating among cisgender women. Present findings highlight high levels of awareness and positive attitudes toward "clean" eating among young people in the U.S., with little recognition of the potential risks of dietary restriction. Further research should examine actual dietary behaviors to clarify potential risks of "clean" eating and related trends and thus inform strategies for eating disorder prevention.