A key element in this factory of consumption and elimination is your intestinal tract. Most people don't realize that your intestines are living things; they're organs just like your heart's an organ. They're not inert tubes; instead, they actively absorb, secrete, send signals, and metabolize.
Depending on what we crave, we have the intestinal freedom to eat plants, animals, or a dozen Krispy Kremes at one sitting. That's because our intestines let us micromanage what we allow within the borders of our bodies.
But with that freedom comes responsibility. As young people, we think that our bodies are like machines, that they'll convert whatever we want to eat to something our cells can convert to energy. That's not entirely true, especially as we get older or don't exercise as much. That's because our bodies respond differently to various types of food.
If you were to stretch your intestines vertically out in front of you (which I'd highly discourage), they'd reach from the ground in your front yard, up past the second floor to your attic window. That's 26 feet of tubing-and this is where the serious plumbing takes place.
The small intestine comes after the stomach and is the tubing where most of food's nutrients are absorbed; the large intestine, or colon, is wider and shorter than the small intestine and absorbs water to form feces.
Just like we all look different on the outside, our intestines respond to the outside world differently on the inside. Kielbasa, for instance, may give your buddies enough energy to hoist trees out the ground, but it may leave you dull and bloated. Either way, it's your small intestine that's screaming clues to you. Its delicate lining is armed with unique immune cells that guard your borders and recognize foods that you-or your ancestors-could not tolerate. When dissed, this finicky organ sends SOS signals to wake you up in the form of gas and spasms. And it rebels by squeezing you.
Find out more about this book:YOU: The Owner's Manual, Updated and Expanded Edition: An Insider's Guide to the Body that Will Make You Healthier and Younger