How do online communities impact men's health? How does hegemonic masculinity harm men's health? In this paper, we analyse an online looksmaxxing community that receives 6 million unique visitors per month and is aimed at men seeking to improve their appearance. We qualitatively analysed 8072 discussion board comments in total. Our findings first demonstrate how users apply a hegemonic masculine gaze as they critique men's bodies (e.g., facial asymmetries and brow ridges). Second, we show how the community encourages men to substantially alter their bodies (e.g., with leg lengthening surgeries or by mewing). Third, we argue that the community subjects users to masculine demoralisation, wherein they are seen as failed men and encouraged to self-harm. Drawing on masculinities theory, we argue that looksmaxxing and similar self-improvement communities harm the health of the men who participate in them.