Why does sweat sometimes smell like onions?

Sense of smell Why sweat can smell like onions

In short: copper increases the smell of sulfur-like compounds, which is why onions or sweat with sulfur compounds smell much stronger in the presence of copper. Whether this is also the reason why mosquitoes flee when copper cent pieces are in the rain barrel or are rubbed on them remains a guess for the hobby gardener. One thing is certain: the new findings from the Munich researchers can help treat olfactory disorders.

Basic knowledge as the basis for new therapeutic approaches

"Even if there are still many unanswered questions, our results help to better understand the connections between the molecular structure of odor receptors and their function," explains Krautwurst, the head of the study. "On the basis of our results and the results of other research groups, we hope to identify approaches to better treat disease-related disorders of the sense of smell."

Indications that smells and flavors go beyond sensory effects

The researchers have now identified and characterized another human, copper-dependent odor receptor. So far, only one of the approximately 400 human olfactory receptors in the world has succeeded in demonstrating a connection between copper ions inside the receptor and its sensitivity to sulfur-containing compounds.

"There is also increasing scientific evidence that smells and flavors have biological effects that go far beyond their known sensory properties," adds Veronika Somoza, who will be the new director of the Leibniz Institute in Freising from November 1st. Researching these relationships using the latest analytical techniques and the most modern high-throughput methods is another important goal that food systems biology has set itself, said Somoza.