As far back as the ancient civilisations we have the first written records of, from Cleopatra’s Egypt to the Romans and Greeks, we know humans have used scents to mask our natural body odour. There are different theories about why our bodies, left unchecked, produce a pungent smell. One is that the primates modern species of humans, including our own Homo Sapiens, evolved from used their stench to discourage potential predators.
But whatever the evolutionary source of our smelly armpits is, it’s a genetic hand-me-down we go to great lengths to escape. From the spices and citrus oils of the ancient world to today’s modern deodorants, few of us are happy to stop at simply washing regularly to keep our BO in check. We go the extra mile to camouflage any whiffs that might accumulate between opportunities to bathe.
Products that mask our naturally occurring body odour are a multi-billion international industry. And in future years, the science behind products that tackle BO look set to take a leap forward after a recent breakthrough in research into the biological mechanism behind body odour. The research, conducted by a team from the University of York and published in the Scientific Reports journal, could eventually lead to a new form of deodorant that prevents body odour at its source.
The researchers have discovered that our underarm body odour results from bacteria living on the surface of the skin splitting odourless molecules secreted into the armpits by sweat glands into amino acids. The bacteria then consume those amino acids as food. But splitting the molecules into amino acids also results in a bi-product called thioalcohol.
Thioalcohol is a volatile substance with a smell that has been compared to sulphur or onions. It’s the main source of the tangy whiff of unwashed human skin, especially prevalent in zones such as our armpits and other nooks and crannies where sweat accumulates.
The big breakthrough from the team from the University of York’s research is the discovery that the production of thioalcohol is down to only a few types of the microbes that make up our armpit ecosystem. These particular bacteria are the only ones that have the “BO enzyme”, that catalyses the thioalcohol reaction as a side-effect of them breaking down molecules into amino acids for lunch.
The scientists were able to prove that by splicing the bacterial gene responsible for the enzyme into another microbe that wasn’t producing it and, subsequently, thioalcohol. Once genetically engineered to include the gene responsible, those previously innocent microbes also started contribute towards thioalcohol production.
The scientists now believe that it should be theoretically possible to find another small molecule that would latch on to the guilty enzyme and stop it from working. There are already numerous drugs that work through targeted enzyme inhibition. A biotech deodorant that included such molecules would, in theory, stop human body odour at source while still leaving friendly microbes untroubled.