Hello!
While there are no foods with negative calories (remember the celery myth?), there are indeed foods that burn more calories than others during the digestion process.
Think about what your body does to digest food: It breaks it down into tiny particles, removes the indigestible fiber (if any), separates out the various nutrients, and then sends them all to the proper place so they can be used or excreted.
Some foods are a lot more work to break down than others, and therefore take more energy (i.e., calories.) Which foods take more energy to break down? You guessed it–Nature Foods.
The reason is fun to visualize. Processed foods were already broken down, chopped, mixed, etc. by the processing plant. The energy that the factory used to break down the food is energy that your body doesn’t have to use. For example, when you eat a whole grain, your body needs to break down the food into particles it can absorb and separate the digestible stuff from the fiber. When you eat flour, your body doesn’t do that work because the flour mill already chopped the grain into particles and removed the fiber. In a way, flour (or any processed food) is partially “pre-digested”. That thought always helps me find processed food less appetizing.
Digesting unprocessed foods is hard work for your body. You can raise your metabolism by up to around 15% by sticking with nature foods. Do the math–that adds up!
Have a good week,
Jill