This case report describes a 26-year-old body builder who had practiced several months of intramuscular self-injection of walnut oil. Apparently this is a normal procedure amongst body-builders. Our patient complained of swelling and tenderness overlying an injection site. Injections of oil may cause foreign body reactions, leading to tumours named according to the injected material; e.g. paraffinoma, oleoma. Systemic distribution has been reported to result in pulmonary complications.