It appears that binge eating along with extreme dieting during teenage years may significantly reduce life expectancy.

http://www.medindia.net/news/Binge-Eating-and-Crash-Dieting-Significantly-Reduce-Life-Expectanc y-36274-1.htm

According to researchers around 10% of fat cells die yearly and are replaced by new ones, however, the number of fat cells a person has remain the same throughout adulthood.

http://www.nytimes.com/2008/05/05/health/research/05fat.html?_r=1&ref=health&oref=slogin