That's what I see among the majority of them.  Most of them live long into their life because they spent the larger portion of it being active/working, eating better, getting around with no problems, or just maintaining a steady, but healthy, weight. Then later gained it once they hit around 50-60 years old (retiring, having problems from being an older age, etc. making them slow down), allowing them to further their life maybe until they're 70-90 years old. For the ones that are overweight as a child and are obese/morbidly obese by their 20s, living to be 50 would be a miracle.