It’s widely believed that old people produce a characteristic, unpleasant body odor. Researchers refer to this as “aging odor” — although it’s more commonly known as “old people smell.” Scientific attempts to identify this odor have been mixed. Some Japanese researchers claim to have identified a volatile chemical (2-nonenal) produced by older people that has a disagreeable, greasy smell. However, an American study couldn’t replicate these findings. The American researchers did agree that there were some age-related differences in body odor, but they concluded that the odors of older people were not unpleasant.