We clearly saw that output is directly proportional to the input we provide to the body. So it is intelligence to look at the input in a deeper sense.

Input is everything you consume (eat and drink). Before going into the details of what, we should understand the how first.

How does our digestive system work? Let us take an example of eating a banana to understand this. When you have a banana what happens inside your body a step wise view.

  1. You start at your mouth and you grind (movement) the banana using your teeth and this process is called mastication or simply chewing.

  2. During the process of mastication, your salivary glands release saliva which moistens the food and starts breaking down the starches(sugars) in the banana.

  3. Tongue helps to position the moistened food (banana) so that it can be swallowed. The banana now moves into the GI tract (like how we do slides in the water theme park) aka swallowing.

  4. The tongue pushed the food to the throat and now the food moves through the throat and the oesophagus. It moves using a phenomenon called as peristalsis (a wave like involuntary constriction and relaxation of the muscles) unlike our theme park slides. It goes through the GI tract and enters the stomach.

  5. In the stomach, the food is mixed with the digestive juices (acids). The proteins in the food are digested here.

  6. Now the food enters the small intestine. Here the food is showered with bile and it digests fats. The walls of the small intestine releases enzymes.

  7. The small intestine is about 5 m long. By using peristalsis (like oesophagus) the food moves through the entire length. When the food leaves the small intestine, most nutrition is absorbed by now.

  8. The pancreatic juices helps with enzymes that helps digesting starches, proteins and fats. The larger molecules keep breaking down into smaller versions as it proceeds deeper and deeper.

  9. Now the food moves into the large intestine. The main role of large intestine is to absorb water, nutrients and salts. The waste is converted into a more solid form so that it can be excreted from the body. The large intestine (colon) ends in the rectum and anal canal and pushes out waste as feaces.

TL/DR version

Digestion is the process of moving food through the GI tract which is about 7 m long. The process begins at the mouth and ends in the small intestine. The food mixes with the digestive juices which helps them break down (large molecules into small ones step by step). The body then absorbs these smaller molecules through the walls of the small intestine into the bloodstream, which delivers them to the rest of the body. Waste products of digestion pass through the large intestine and out of the body as a solid matter called stool/feaces.

This is what happens to your banana and anything you consume. You might have learnt this in your biology classes of your middle school. The above is just to remind you all the steps that happens in digesting any food and the robustness of the system.

So by now, you understand that the act of digestion is to break down food into nutrients which the body uses for energy, growth, and cell repair. The body understands only molecules. It doesn’t care if it is banana or donut or a pasta or a pizza. All foods and drinks it will convert into smallest molecules of nutrients before the blood absorbs them and carries them to cells throughout the body.

Now that you know what is the purpose of digestion and how the process works next we can talk about what is the right input.

spoiler: nutrition 🤓

🥂to input!

Thank you for sharing your attention currency with me 🙏

If someone in your circle will benefit from this series, please pass them the details and ask them to subscribe here

If you would like to connect with the human behind the series, you can find me in Twitter and LinkedIn