Why Does My Sweat Smell Like Onions?

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The sweat of men and women have different characteristic odors, according to “Discover” magazine. The odor is not caused by the sweat itself. Bacteria that live on the body ingest compounds present in the sweat, the metabolism of which causes the smell. Men and women have different chemical components of their sweat, which causes women’s sweat to smell like onions, while men’s sweat smells like cheese.

When Swiss researchers investigated the differences in the odors of sweat from men and women, they found that the assessors all agreed that women produced sweat with a more objectionable odor than that of men. The researchers found that women produced 10 times the amount of sulfur-containing compounds that men did, according to “Discover.” When the skin-dwelling bacteria digest these compounds, it produces a chemical called thiol, which is notorious for smelling like onions. By contrast, men produced sweat that had a higher concentration of fatty acids than women did.

A person’s diet has an impact on their body odor, reports HowStuffWorks. Foods such as garlic, onions, fermented cheeses and cruciferous vegetables can cause objectionable-smelling sweat. Additionally, alcohol escapes through the pores of the skin. It does not matter what type of alcohol was ingested; the chemical process is the same regardless of whether a person consumed beer, wine or liquor.