I had an embarrassing moment when I was a student. My backpack was taken by a girlfriend for a trip. She gave me the backpack when she came back.

You have to sweat a lot because your backpack stinks. The smells like onions. I don't know what to say.

I stood there with no one around to hear me. I don't know how I answered. I thought to myself, "I don't eat onions very often." Do my sweat smells bad?

It was 25 years ago that I discovered that my stinky sweat was a sign of something good on my skin and that it protects me from dangerous infections such as MRSA.

What creates your body's unique bouquet?

To figure out what I'm talking about, we need to take a closer look at what makes body odor. The sweat isn't the thing.

"No, I don't think you smell by yourself," says Thomas. It doesn't have the stinky, odorous molecule.

Humans have a specific bouquet of smells. He says that sweat is odorless after it leaves your skin.

He said that most sweat is salty water. It's the sweat that's on your body and it cools you down when you're hot.

He says that they're not interested in that. We are interested in the type of sweat that is produced in our genitals.

This other type of sweat contains a lot of compounds, including oils and fats.

Humans have two different types of sweat. Thomas says that it probably has to do with the odors that it emits.

This type of sweat is not smelly. Tiny creatures take that sweat and make it stinky.

I am talking about the organisms on your skin.

The human skin has over 200 different types ofbacteria on it. Each person has their own strain of thesebacteria. The skin has so many different things in it.

Thesebacteria are thirsty. Some of them like to eat the molecule in our sweat. Some of the compounds they spit out are aromatic. The American Society for Microbiology claims that they can smell like goats.

Some of the molecule are stinky.

"We've had people describe it as kind of an onion smell or a cheese smell," he says. The compounds do smell bad.

But wait! This critter – and your stinky sweat – is actually beneficial and even necessary.

Back in college, when my backpack smelled a bit stinky, it wasn't my sweat that was to blame, but a small bug called Staphylococcus hominins.

It might make you want to take a shower. Wait! There is something you need to know before you use the soap. I didn't know that thesebacteria and their relatives do a great job for you and your skin. You have to have thesebacteria.

Richard Gallo is a professor at the University of California, San Diego.

Over the past five years, Gallo, Nakatsuji and their colleagues have published a number of studies showing how S. hominins protects our skin from a number of infections.

The team has developed a cream that can be used as a treatment for the skin condition.

Gallo says that S. hominins make a type of antibiotic that targets the MRSAbacteria. punching holes in the cell is what it does to kill thebacteria.

Gallo says that the other parts of your skin can also produce antimicrobial agents. It was 20 years ago that he and his colleagues discovered that your body makes antimicrobial molecule inside of your sweat.

Gallo says sweat is similar to an antibiotic juice. The antibiotics increase in concentration when the water goes away. It leaves a thin layer on your skin. Our skin tries to fight the badbacteria.

Take a moment to thank your sweat and thebacteria that eat it for keeping your skin healthy and safe, the next time you're hot, sticky and stinky.

Even if you use antibacterial soap, the protective creatures will still be there to help you.

He says that you get rid of the material on the surface of your skin by washing it. detergents and antibiotics can't get to the deep inside of your skin's pores. Within 10 minutes after washing, your skin's surface is colonized with the same type ofbacteria.

He says that your skin is smarter than you. You don't know what it needs better.