Sixty-eight year old woman, 5'2". Jazzercise 5 times a week. Take the weekends off. I did the Atkins diet for 9 years, never got all the way to goal, but went from 168 to 134 and maintained for 8 years. It was a struggle. I never experienced the loss of appetite others mentioned. When I started to tweak the diet by adding whole grains and fruit, my weight creeped back up to 161. logging my daily intake into Fitday.com and counting calories slowly helped, but it was a struggle. I got down to 150 and there I stayed.