The Dukan Diet, made popular when Kate Middleton and her mother reportedly followed the plan to slim down in preparation for the royal wedding, is back. French physician Pierre Dukan, M.D.'s third U.S. book, The Dukan Diet Made Easy, comes out May 20.

Overall the diet is the same, with four phases: attack, cruise, consolidation, and stabilization.

The attack phase is geared for fast weight loss to boost motivatation and can last up to seven days. During this phase, the diet consists of unlimited amounts of only lean protein-lean beef, poultry, lean ham, organ meats, fish and seafood, eggs, and nonfat dairy (except cheese)-in addition to supplementing with 1 1/2 tablespoons of oat bran daily.

Next comes the cruise phase, where you alternate between days of all protein and days of protein and non-starchy vegetables, along with the oat bran. You stay in this phase until you reach your goal or "true" weight, as Dukan likes to call it.

Then you move on to the consolidation phase that lasts for five days for every pound you lost. At this point you can reintroduce limited amounts of fresh fruit, whole-wheat bread, and cheese into your diet, plus enjoy two weekly servings of starchy foods, such as pasta, beans, or potatoes. However you must still follow the pure protein diet from the attack phase for one day a week (for some reason, the plan says on Thursdays) and continue to supplement with the oat bran.

Lastly is the stabilization phase where you can basically eat whatever you want, but you need to include one Thursday of pure protein each week and 3 tablespoons of oat bran daily. This phase is suggested for the rest of your life.

With this new book, you can now follow the program online. The website promotes personalized, individual counseling for a membership fee. You start by having your "true" weight calculated and by answering 80 personal questions, which then creates your diet plan. Every morning you receive daily instructions and tips, and in the evening you report back on how are you feeling. Chat rooms, recipes, and many other tools are made available.

I think this type of membership could be helpful for many people, and it actually reminds me of Weight Watchers, of which I am a fan. Unfortunately though, online counseling or not, the diet plan is still the same. There are some pros to this diet; for example, eating plenty of veggies (even though he does limit the types) and lean protein, drinking lots of water, and daily exercise are all things I recommend too, but the cons still outweigh these high notes.

The main problem with the Duakn Diet is that for the longest time the diet consists of mostly protein. Sure you will lose weight, but at what cost? No diet should leave you feeling poorly, and with a restrictive, low-carb and low-fiber diet, you probably will. It can cause constipation, and most importantly put your body into ketosis (without adequate carbs your body breaks down fat for energy), which can cause fatigue, bad breath, and dry mouth; and eventually damage your kidneys and liver. Why anyone would even want to deal with that is beyond me.