I heard about paleo from a friend and was just interested mainly for the weight loss..  Pre-Paleo i was about 185 lbs and 15-18% body fat; i needed at least 4-6 cups of coffee/day just to keep "energized."

After 5 months of moderately orthodox paleo (i eat yams and clarified butter), i realize it was the best decision of my life. Now i'm at 160 lbs and 10% body fat! i only drink about 1-2 cups of coffee/day and i'm still mentally alert all day. And even with the weight loss, i've continued increase my strength gains during weight lifting!

The best part is that i've unintentionally converted a few people to Paleo; two coworkers and a friend noticed these changes, started asking me questions, and within a few weeks they all were going through ketosis