There's a ton of research on reduced calorie diets, and my physician referred me to this program, and it's run by my hospital system. I meet with dietitians, physical trainers, social workers, and physicians monthly.
/shrug
I don't really know how to evaluate it much better than that.
There is a massive amount of info supporting ketogenic diets and fasting. I'd recommend you look into the Keto Talk and Fasting Talk podcasts and read Jimmy Moore's books: Keto Clarity and the Complete Guide to Fasting. Also, congrats on your progress and keep it up! I dropped over 60 pounds (started at 215 lbs, now at 152 and very lean) doing what you're doing.
But ceejayoz's advice is good advice... always do your own research!
