Weight loss gets harder after 50, and I found that out for myself on a random Sunday morning with the smell of cinnamon rolls filling up my kitchen. My husband had snuck a package into the cart the day before. I found them at checkout and asked him how in the world they got there. He told me they "jumped in on their own" and he "had nothing to do with it." That man keeps me laughing. But that cinnamon roll moment is exactly why I want to talk about commitment today. Around 45% of people make some kind of promise to eat better or move more this…