Here are 11 things that carbs are responsible for within the body. So when you’re under the impression you need to avoid them because “they’re the enemy”, here’s what you’re probably not doing well: 1. Primary energy source 2. Brain function 3. Muscle function 4. Metabolism regulation 5. Digestive health 6. Blood sugar regulation 7. Hormonal balance 8. Exercise performance 9. Protein sparing 10. Immune function 11. Fat utilization