In this article, I engage with food and food preparation as a site for the performance and regulation of masculinities. I probe contemporary rationalized body culture and the forms of food, social domination, scientific knowledge and normative discourses that are part of the sport of mixed martial arts (MMA). I examine manifold dietary discourses, food consumption and preparation practices related to MMA to illuminate how MMA fighters' involvement in the sport involves the subjection of their own bodies to rigorous dietary regimes, but also the domination of female bodies in relation to food preparation. This article demonstrates how 'eating clean' involves a perception of certain foods and supplements as clean. This is centered on producing a body-for-masculine performance that is fast, strong and capable of giving and taking pain. It involves an ascetic lifestyle that involves the rejection of fast food and other 'dirty' foods that would pollute or slow down the violent bodies of MMA fighters. A four-year ethnography of MMA, advertising of 'MMA supplements', and online articles regarding MMA dietary regimes forms the empirical basis of this article.