Dr. Ian Smith's new 4 Day Diet and the 50 million pound challenge

Dr. Ian Smith was on the Today show to chat up his latest book, The 4 Day Diet. Smith, who is also working with State Farm on its 50 Million Pound Challenge, also is the author behind the Fat Smash diet books.

So what's different about this plan? It's only 4 days -- well, 4 days at a time. Those 4-day modules are:

• Induction (detox/cleansing)
• Transition (to reintroduce all food groups)
• Protein Stretch (to avoid plateaus)
• Smooth (when you can have some formerly forbidden foods like pizza and French fries)
• Push (the sprint just before the final stretch, back to a stricter eating plan)
• Pace (a comfortable module for you to catch your breath)
• Vigorous (the final module to lose those last few pounds)

So you work on specific tools to build a lasting weight loss. The diet is based on clean whole foods (no calorie counting) and getting your mind in the right place.