You may be sitting their with a question mark over your head trying to figure out what campfires have to do with an exercise science. If you can follow this awesome visual our professor used in class (and I don’t totally butcher it) you’ll understand. Hopefully you’ll have the same a-ha moment I had.
When you build a campfire, you put logs down. Some people put newspapers under the logs. However, when you light the newspaper it lights fast but burns out quick–the logs don’t have enough time to catch from the newspaper. To build a good fire, you use kindling (like twigs) that catch quickly but burn longer. The longer burn from the kindling will ignite the logs and your fire will burn.
This is very simplistic, obviously, but think of it like this. The newspaper is your simple carbs–white rice, processed foods, white bread, etc. The kindling is your complex carbs–vegetables, beans, whole grains, etc. The logs are fat. It is infinitely harder to lose weight if you eat simple carbs. Your body will work better and more harmoniously, if you start off with complex carbs and in turn, you will burn fat better.
It’s simple and beautiful, and it really resonated with me. Obviously, it doesn’t include a lot of the why it works–that starts getting into chemical reactions and mind-numbingly scientific stuff–nor does it address other issues (like quantity), but it makes it very clear why you should look at what you eat.