What causes the smell of old books

Body odorHow our very own Fragrance note arises

Everyone has their own unique smell. It is made up of different substances. The immune system could be crucial for this. We talk about it with the biologist and physician Hanns Hatt.

When we sweat, we sometimes smell quite intense. The smell of sweat is caused, among other things, by glands in the skin, explains Hanns Hatt, biologist and doctor. However, these glands only produce part of the odor molecules; another part is produced by bacteria that colonize our body. A third point is the food.

Fresh sweat doesn't stink

Normal sweat, caused simply by exercise or heat, is mostly made up of water. It doesn't smell like anything, says Hanns Hatt. When we do sport and sweat, the corresponding sweat glands on the body's surface are switched on: "So that there is a lot of water on the surface. And water evaporates, and with it I cool my body."

The other sweat that arises under the armpits or in the genital area smells. We find that uncomfortable. Hanns Hatt says that we are the only living beings and that it is purely a matter of upbringing: "There is no one in the animal kingdom except us who cannot stand sweat. We were raised by our parents: You sweat, you stink, now wash Yourself! "

"You can also influence the smell of sweat by eating."
Hanns Hatt, biologist and physician with a focus on odor research

However, this sweat is of great importance for human communication, explains the biologist Hanns Hatt. Because everyone creates their own fragrance - their own perfume, as Hatt calls it. "We are all perfumers and we make a fragrance that is so specific for a person that no one else in the world has it exactly. An olfactory fingerprint."

Experts call our unique smell the olfactory fingerprint and it is determined by our genes. "We can basically smell the genes of our fellow human beings." This personal sweat plays a major role in the choice of a partner, because we use this smell to find the genetically suitable partner.

"There are people who produce an incredible amount of these stinky fatty acids and some who produce an incredible amount."
Hanns Hatt, biologist and physician with a focus on odor research

The note in our sweat that we find particularly uncomfortable. This sweaty, rancid, sour scent comes exclusively from the bacteria that break down lactic acid on the skin, explains Hanns Hatt. That's why fresh sweat doesn't stink.

Food also plays a crucial role in our body odor. Vegetarians, for example, smell different from meat eaters. Hanns Hatt says that food gets into the blood via digestion and via the blood into sweat, which is then excreted through the skin at some point.

More on the subject:

  • Bed bugs love dirty laundry | Anyone who comes home from vacation with small, itchy bites may have had bed bugs. There are more and more - and we are the reason for that.
  • Vegetarians smell better | Those who do without meat smell better. In one study, male sweat was presented to female test subjects. Sweat from people who had not eaten meat for two weeks was more popular with women.
  • Why it is good when we sweat | 33.3 degrees in Saxony-Anhalt, 32.6 degrees in Brandenburg: This week it is warmer in Germany than it has ever been this year. Sweat stains and drops are guaranteed. And that's good.