This case presentation describes a 48-year-old man who experienced subcutaneous nodules 9 months after self-injection of sesame seed oil into the pectoral area for muscle augmentation. This procedure was reported by our patient to be frequently performed in the body-building and fitness scene. Ultrasound imaging showed multiple, low reflecting round nodular areas of up to 1 cm diameter in both breasts. Excision of a representative nodule revealed a cyst filled with oily material, surrounded by granulomatous tissue. This case report demonstrates an unusual side effect of augmentation measures in body-builders.