Who are you? It turns out it's a tricky question both when it comes to life, and biology. Because among the countless unique and special cells in our body, there are trillions of microorganisms living in and on us. As the episode of AsapSCIENCE above explains, this huge colony hitching a ride with us is known as our microbiome, and we've picked it up throughout our life through our nose, ears, mouth, eyes, and other entry points. These microorganisms contain around 22 million genes of their own DNA that not only control their own cells, but also control processes in our body.

Scientists are quickly coming to realise that the diversity and composition of our microbiome is crucial to our immune system, weight and even our ability to respond to stress.

Conditions such as obesity, allergies, acne and depression are all being linked to the health of our microbiome, and there may even come a point where doctors diagnose you by your microbiome, rather than your own cells.

There's also a lot of research being done on poop transplants, which are exactly what they sound like - the poo from a person with healthy gut bacteria is transferred into the colon of someone with a sick microbiome.

You might think that's pretty gross (and OK, it probably is) but amazing, studies have shown that they can be far more effective than antibiotics at treating infection. Scientists have also found that when the poo from lean mice is transplanted into the colon of obese mice, it can help the obese mice lose weight even when their diet doesn't change.

But don't worry - you may not be who you think you are, but the best part about all this research is that you're more in control than you previously imagined. Watch the fascinating episode above to find out more about the foods that can help encourage a healthy microbiome, and how these microorganisms affect our life.