Not OP, but you have to keep in mind that your body is always trying to repair any damages that happen. Be it through actual accidents or molecular mishaps. Stress and other factors can cause the body to go into survival mode, where all resources are allocated to solving only the challenge directly ahead at the expense of repairs. And your body always needs repairs, because there is so much stuff going on at the molecular level that wears down the cells. Our bodies are pretty good at repairs but not perfect.