Why does metabolism slow down as you get older?

Answer 1

Just like if you sit around and play with a rubber band for 70+ years, it will eventually wear out and start to break down. The same happens in your body when you age. Everything is working 24/7 every year of your life so it will start to slow down. Also, the elderly are usually less active than when they were younger, I don't know EXACTLY how, but you always hear that "the more active you are, the faster your metabolism is". Hope that helps :-)