Ninety-six patients with hip conditions requiring total hip arthroplasty were randomized to receive either a 32-mm metal head (n=48) or a 36-44 mm metal head (n=48). The primary outcome of interest was the level of blood metal ions (chrome, cobalt, and titanium). Secondary outcomes included patient-reported outcome measures (PROMs) using the Oxford Hip Score (OHS) and the University of California, Los Angeles (UCLA) activity score. Outcomes were assessed at two- and five-years follow-up. Overall, the results of the study revealed no significant differences in blood metal ion levels between the two groups at five years, nor in PROMs between participants with or without elevated blood metal ions. The study suggests that femoral head size does not impact metal ion release in the short to mid-term follow-up.