I am not very successful with sticking to it however I believe in the 'paleo lifestyle' or diet. Some have talked about the Atkiens diet and although it is similar Paleo is (or should be) a good balance of healthy organic vegetables and natural grass fed meat. Ideally in the 'zone diet' proportions.
The idea is that we were healthier 10,000+ years ago when we were hunter gatherers and going to grains and agriculture were bad for us.
Key points :
No grains (or rice etc)
No dairy
No legumes
No sugar or processed foods.
Marksdailyapple.com is a good resource if interested.