How does what's going on in the digestive system affect the brain? Now that I understand more about how the body works, I realize if your digestive system isn't working, the rest of your body can't possibly work! But I have to say that for most of my life I just thought of food and digestion as calories and fat. I wanted to be sure I didn't eat too many calories, because that's the important thing, right? Being overweight makes you unhealthy, right?

I didn't pay attention to the fact that:

"Every cell that makes up every tissue that makes up every organ DEPENDS on the body's digestive system to provide nutrients it needs to keep functioning."