On and in you

your body full of microbes

You can’t see them, but they’re there. Microbes. They’re on you, in you, and you carry more than 100 trillion of them all by yourself. That’s fourteen thousand times more than the number of people on earth. Collectively, they’re known as human microbiota.

You and your 1.5 kilos of microbes

Your body is chock full of microorganisms, including bacteria, fungi, archaea and viruses. Altogether, there are ten times more microbes in your body than there are human cells. Together, they make up about 1.5 kilograms of your body weight.

microscopic reinforcements

1.5kg

A new view of the body

Your body’s own microbes are important to your health. That’s why it’s handy to know what kind of microbes are carried by the human body. In the past few years, a revolution has taken place in this field. Research groups all over the world are using the newest technology to map out the human microbiome. We are therefore seeing our bodies in a whole new way.

the body, rediscovered

Mouthful of microbes

Your mouth is full of microorganisms. All kinds of fungi, archaea and viruses, and about 700 species of bacteria, live there. Most of them are harmless and keep your mouth healthy. But some cause cavities, gingivitis or bad breath.

to each his own mouth content

700 different species of
bacteria live inside
your mouth

Biggest organ, smallest protectors

The skin forms an important barrier against microbes from the outside world. In total, you have about 1.8 m² of skin, and more than 1.5 trillion (that’s a 1 with 12 zeros) bacteria live on it. In some wet places, tens of millions of microbes live on every square centimetre of skin. The majority of them are useful and harmless. They prevent harmful bacteria on your skin from ever getting their feet in the door.

first line of defence

1.5

trillion
microbes

A one by twelve zeros. That’s how many microbes live on the entire surface of your skin.

Slimy defence

With every breath, you take in tidal waves of microbes. Some of them can be harmful to your health. The mucous membranes in your nasal cavities and airways produce mucous, and foreign microbes stick to that mucous. This means of protection, along with your skin, form your body’s first line of defence against harmful microorganisms.

slimy trap

A hidden world in your intestines

Your intestines are the undisputed capital of your microbiome. Of the 100 thousand billion microbes in your entire body, the vast majority lives in your intestines. That’s an enormous proportion, with a role in your health that should not be underestimated. Intestinal microbiota consists primarily of bacteria, about 1,200 different species. It’s so many bacteria, in fact, that almost half of all your poop is made up of intestinal bacteria.

microbe valhalla unique intestinal life

50%

of your feces
consists of
intestinal bacteria.

Intimate helpers

From a microbial perspective, genitals are also very interesting. Microbiologists are particularly interested in female genitalia. The unique environment in the vagina cannot be found anywhere else on the body. This hostess offers a place for a wide range of microbes. That includes 300 bacterial species, which are primarily lactic acid bacteria.

healthy acidity

Pathogens

A tiny fraction of microbes can be dangerous for humans. Your body’s own microbes cooperate with your immune system to protect you against these illness-causers, called pathogens. But, everyone becomes ill sometimes. Approximately 17 million people, including many children, still die every year from infections. How can you harm yourself against that?

invisible danger microbes and medicine

The expert explains

Microbes on and in our bodies: Why are they important for our health? What do we know about them so far? And how can we apply this knowledge? Remco Kort, microbiologist and scientist at TNO (Netherlands Organisation for Applied Scientific Research), investigates this.

watch the video