The present cross-sectional study aimed to examine the influence of diet on brain creatine (Cr) content by comparing vegetarians with omnivores. Brain Cr content in the posterior cingulate cortex was assessed by proton magnetic resonance spectroscopy (1H-MRS). Dietary Cr intake was assessed by 3 d food recalls. Vegetarians had lower dietary Cr intake than omnivores (0·03 (sd 0·01) v. 1·34 (sd 0·62) g/d, respectively; P= 0·005). However, vegetarians and omnivores had comparable brain total Cr content (5·999 (sd 0·811) v. 5·917 (sd 0·665) IU, respectively; P= 0·77). In conclusion, dietary Cr did not influence brain Cr content in healthy individuals, suggesting that in normal conditions brain is dependent on its own Cr synthesis.