The investigators will examine whether compulsivity in those who score above-average (but
below clinical cut-off) on an eating disorder questionnaire can be altered by 9 days of
N-acetyl cysteine (NAC). N-acetyl cysteine has been shown to be of some benefit in
individuals with other compulsive disorders, such as trichotillomania and addiction, so this
research investigates whether a short period of time taking N-acetyl cysteine changes
compulsivity, measured using cognitive tasks and questionnaires.