Thinking of trying the Dukan Diet? Read this first…

What is it and does it work?

The Dukan Diet seems to be everywhere at the moment.  From celebrities like Jennifer Lopez, the Middletons and Gisele Bundchen to friends and family, everyone is on it in the hope that they will be able to quickly shed a few pounds.  And there-in lies the trouble – people are yet again turning to the latest diet fad for a quick fix solution.  Now as much as that irks me, that’s a post for another time!

The Dukan Diet is the baby of Dr Pierre Dukan and it consists of 4 phases, each one following the other.  His belief is that a high protein, low carbohydrate and low fat way of eating is the key to weight loss, thus the initial phases of the diet are all based upon this.  Here is a brief outline of each phase:

Phase 1: The Attack Phase

This consists of consuming nothing but low fat protein sources and is designed to kick start the weight loss process.  Think chicken, fish and lean meats.  Oat bran is recommend to stimulate bowl movements (protein lacks the necessary fibre to aid this).  No oil, butter or cream is allowed nor is any sugar (although sweetener is permitted).  This phase lasts between 3 to 10 days depending on how much weight you need to lose.

Phase 2: The Cruise Phase

This makes up the bulk of the plan and alternates between protein only days (as per phase 1) and protein with vegetable days (although starchy carbohydrates like peas, lentils, carrots and potatoes are to be avoided). This phase lasts until you have reached your goal weight.

Phase 3: Consolidation

Once you have reached your goal weight you start the ‘consolidation’ phase, which has a very specific timescale of five days for every 1lb you lose.  That means if you’ve lost 20lb you will need to follow this phase for 100 days!  You continue as per phase 2, but with the introduction of certain fruits, 2 slices of wholemeal bread and 40g of cheese.  Two celebratory meals per week are also permitted.  One portion of starchy carbohydrates a week is allowed during the first half of the phase and this increases to 2 portions a week during the second half.

Phase 4: Stabilisation

This is the diet you are then expected to eat for the rest of your life.  You  are supposed to eat a balanced diet everyday apart from Thursdays, which should consist of meals containing protein only.

So, having outlined what the Dukan diet is, let’s take a look at some of the pros and cons.


  • If you follow the diet exactly, you should lose a large amount of ‘weight’ relatively quickly, which can be motivating for some.  I say ‘weight’ because this will be a combination of water, fat and muscle, not just fat.
  • The strict set of rules may appeal to some people’s personalities who like having a specific structure to follow.
  • The diet encourages people to remove sugar, processed and refined foods from their diet, which is a huge plus in my book.
  • There is no need for calorie counting.
  • Having a strict plan can make menu planning easy (albeit monotonous).
  • Consuming protein only foods in the attack phase should keep you full, and the lack of variety is likely to lead to boredom, in turn making you eat less leading to weight loss.


  • Apart from the addition of oat bran and low fat dairy products, there is nothing really new or inspiring to this typical high protein, low carbohydrate diet.
  • The diet does not allow sugars, however the consumption of sweeteners is permitted.  For me personally this is simply wrong.  Sweeteners are nothing more than a man made toxin and have no place in a healthy diet.
  • Low fat everything.  You need healthy fats in your diet.  It’s as simple as that.  Good fat is the cornerstone of every cell in our body, and is crucial for brain and nerve function (the brain is 60% fat), skin health, balancing hormones and a host of other functions within the body.  The vitamins A, D, E and K are fat soluble, therefore eating a low fat diet can make us deficient in these crucial vitamins.
  • The diet is very strict – there is no room for cheating.  Any errors mean that you essentially have to start from the beginning.
  • The ‘attack’ and ‘cruise’ phases are very limiting, so chances are that you will get bored very quickly.  This is especially true for those who have a lot of weight to lose as they will be on these phases for a longer period of time than most.
  • This diet is based on a one size fits all policy, but we all know that everyone is unique with differing needs.  I do not believe that this diet teaches people about healthy balanced eating.
  • There is a lack of vitamins and minerals due to the limited fruit and vegetable intake.  The low levels of Vitamin C which is needed to absorb iron can leave you feeling tired.
  • The average calorie intake during the ‘attack’ phase is just shy of 1000 calories – macronutrient (protein, fat and carbohydrate) composition aside – this isn’t sufficient to support the energy needs of the average person.  Daily walking is encouraged, however those of you who partake in high intensity exercise will find it difficult to maintain due to lack of energy.
  • Motivation to stick to the diet, especially for those with a lot of weight to lose can be tested as the meals/plan can get monotonous.
  • The lack of fibre can cause intestinal problems such as constipation.  The oat bran is designed to deal with this however it is not something that should be consumed on a daily basis as it contains phytates, which reduce the absorption of iron and zinc in the body.   Fibre should be obtained predominantly through vegetable sources to keep the bowel healthy.
  • If you don’t do exactly what the book says then you will gain the weight back quickly, and sometimes gain more than you lost.

My verdict: Dukan’t

Of course you will lose weight quickly initially with this diet, although it must be remembered that this will largely be water.   Water is bound to carbohydrates, so when you eliminate these in your diet your body turns to stored sources of glycogen (sugar) in the body to burn for energy.  When it does this the water attached to it is broken down and eliminated from the body – hence the ‘weight’ loss.  If/when you return to ‘normal’ eating patterns the weight will return.  It would be far better to pursue a healthy diet that works within your own needs and lifestyle, as you are far more likely to stick to it and achieve your goals.

Having reviewed a number of diets over the years I don’t see much difference in this to others that are out there.  In reality this diet ‘break-through’ like many before it simply comes down to the same principle of weight loss achieved through a reduced calorie intake.  The diet is extreme and I genuinely don’t believe you have to exist solely on protein to lose weight – there are much healthier and maintainable ways of doing so. I am actually in favour of the reduced sugar and carbohydrate intake as part of this diet as I think most people over consume these, however the slimming phases are severely lacking in energy, essential vitamins and minerals.  The pure monotony of the Dukan diet is also likely to result in ‘falling off the wagon’.  The long-term effects to one’s health of following such a strict regime are  currently unknown so caution should be taken when embarking upon something like this.

Overall I would definitely say give this a miss.  The excitement of the initial weight loss will be overturned by the rapid onset of weight gain after you start eating normally again.