Hey, I’m Escherichia Coli, but you can call me Chia. I’m a leaf loving bacteria, and my journey has just begun. Traveling through the birth canal, I entered baby Sarah’s body. I live in the gut, and so do my friends Roi, Archy, and Firmi. Meet Roi — he’s a Bacteroid, which means he karate chops sugars like a ninja. Archy is an Archaea, and he loves his lipids. Protein and dairy are what keep him going. Then there’s Firmi. She’s a Firmicute, and trust me, she isn’t cute. Firmicute crave sugars, and are needed to absorb fat into the body. Having too many of them around could result in some serious problems. Last, but definitely not least, is Sarah. She’s a newborn whose gut is what we call home. We are not the only ones here — everyone’s body is home to trillions of bacteria. In fact, you have more bacteria than cells, so you are actually more bacterial than human! A mother’s milk contains special sugars that are meant to feed, support, defend, and influence the immune system. It takes up to two years until a healthy microbe community has formed.1 It’s amazing that the Quran instructs a mother to suckle her child for two full years (2:233)! The set of bacteria that develop is unique to each human and is called the microbiome. Here in the microbiome, I’ve been getting lots of healthy nutrients from Sarah. Archy’s living the life — after all, the only thing Sarah drinks is milk! Roi has been busy breaking down lots of good sugars, and Firmi has to survive on those. She’s scheming until Sarah can get her hands on a cookie jar. Now that Sarah is fourteen, most of her food choices are influenced by her friends. She used to have a pretty balanced diet, but the vending machine has helped Firmi grow rapidly. Everyone’s gut is like a garden, and we choose what we grow based on our dietary choices. If someone starts eating a lot of junk food, harmful bacteria will start growing and taking resources from the veggie-loving bacteria. The growing bacteria will send signals to the brain to continue making unhealthy choices. It’s a vicious cycle, and I’m afraid we’re already in it. The good guys are deteriorating. Firmi, the queen of the microbiome is giving the brain orders to crave more fast food . Sarah’s definitely not well, she’s unable to focus, and stressed about her weight gain. The Quran advises to eat halal but specifically nutritious (5:4). We still may have a chance – Sarah is intelligent, and could change her ways! Fuelled by a sugary diet, Firmi and her cronies are officially at war with the microbiome. I start to produce serotonin to communicate with the brain, and Archy initiates the immune system alarm. Roi squeezes himself into the vagus nerve, the information highway of the nervous system, and convinces the brain to choose something beneficial for the body. Sarah decides to eat a salad. As the nutrients reach me in the gut, I start to battle Firmi. She begins to shrink and we are able to win! With Firmi restrained to only healthy sugars and fats, the inhabitants of the microbiome are now her best friends. Citations:  J. Rodríguez, K. Murphy, C. Stanton, R. Ross, O. Kober, N. Juge, E. Avershina, K. Rudi, A. Narbad, M. Jenmalm, J. Marchesi and M. Collado, “The composition of the gut microbiota throughout life, with an emphasis on early life”, Microbial Ecology in Health & Disease, vol. 26, no. 0, 2015.  J. Alcock, C. Maley and C. Aktipis, “Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms”, BioEssays, vol. 36, no. 10, pp. 940-949, 2014.