According to a memory of his son, Kashiwa OYAMA, Iwao gobbled up a bowl of rice topped with a more than 40 cm of kabayaki (grilled and seasoned with a slightly thick, slightly sweet sauce) eel, and favored beefsteaks and red wine imported from France, thus Iwao's weight was more than 95 kg when he was the heaviest.
息子の大山柏の回想によると40cm以上もある鰻の蒲焼がのった鰻丼ペロリと完食し、ビーフステーキとフランスから輸入した赤ワインが好物で、体重は最も重いときで95kgを越えていたという。