7 Problems with the Dukan Diet

I stumbled upon an informative post that covers the pros and cons of the dukan Diet. Encouraged by its versatile approach to describing pros and cons I decided to put in my two cents’ worth.

The post can be found here (hubpages). The author of that post, Amber Allen, has listed some of the most common charges against the Dukan Diet. I believe she was being objective and garnered the widespread opinions (that I find baseless). Don’t get me wrong, I do not claim that the Dukan Diet is a flawless weight loss program. The thing is I just want my readers to get the both sides of the story.

Problem #1: Health

From a health point of view following a high protein diet like the Dukan Diet can produce a number of different side effects

  • High Cholesterol – although losing weight usually helps lower your cholesterol levels in the long-term if you chose your protein sources predominately from high cholesterol foods such as red meat and eggs your cholesterol levels may increase.
  • Gout – a high protein diet is just one of many factors that can lead to you suffering from gout. Other things such as your family history, age, gender and level of alcohol consumption also influence whether you are likely to suffer.
  • Constipation – On the days you eat only protein the likelihood of being constipated is increased. Dr Dukan recognised this problem and to combat it you are required to drink a lot of water and to eat oat bran. If you do suffer with constipation you may find it helpful to miss out the initial Attack Phase where you eat only protein and go straight to the steady weight loss Cruise Phase where you also eat some vegetables.

Let’s take a closer look at those problems.


High level of cholesterol is not directly connected with foods that contain cholesterol (and not with eggs n particular; see the quote below). Besides, there’s no rule that says one must eat eggs or red meat on Dukan Diet. There’s a variety of other choices. Many overweight and obese people are having problems with cholesterol while not on any diet. On the contrary, their ‘non-diet’, junk food does much more to increasing the level of cholesterol than high-protein food in Dukan Diet.

Researchers reviewed the results of several different studies on eggs and nutrition, concluding that eggs did not contribute significantly to the body’s cholesterol levels. Although eggs are in fact a high-cholesterol food, the researchers note that only one-third of the body’s cholesterol comes from dietary sources; the rest is produced by the body from saturated fats. As a consequence, saturated fat intake plays a far more significant role.  Source:

Dukan’s method restricts the saturated fat intake. Moreover, a stable decrease in cholesterol level seems to be the long-term result of losing weight.


I agree, there might be some weak connection between eating meat / seafood and gout. According to Wikipedia:

Dietary causes account for about 12% of gout, and include a strong association with the consumption of alcohol, fructose-sweetened drinks, meat, and seafood.

But in the same time:

Recent studies have found dietary factors once believed to be associated are in fact not, including the intake of purine-rich vegetables and total protein.


The consumption of coffee, vitamin C and dairy products as well as physical fitness appear to decrease the risk.

So basically, if you really believe you’re in a group of high risk, choose diary over meat. There’s not enough evidence to support the hypothesis of the connection between gout and Dukan Diet. If you’re afraid of gout I’d worry about alcohol, sweets and sedentary lifestyle rather than a weight loss program.


I agree that, the Dukan’s menu is poor in dietary fiber but, providing that one follows the instructions closely, the oat bran supplementation should be enough to prevent the constipation problems. Besides, if the oat bran is not enough, after the Phase I, you can have a number of fiber rich vegetables.

Problem #2: Induction Flu

Induction Flu isn’t a type of flu at all it is a colloquialism used to describe the withdrawal symptoms your body experiences as you switch from carbohydrates to protein and your own body fat to fuel your body. Apart from not having a chill or fever the symptoms are very similar to flu. In addition to having a bad headache you can also feel nauseous, lethargic and irritable and be unable to concentrate. The good news(?) is that it should last only 2 to 3 days and if you plan for it to happen it should not divert you from your objective.

There’s not much to argue with here except that the withdrawal symptoms are not caused by the body switching from carbs to fat. A sudden cut in simple sugars supply is more likely to be a reason. Sugar can be addictive as drugs or alcohol. Heavy sugar users can experience a ‘withdrawal syndrome’. The induction flu only proves the extent to what we are addicted to sugar. I agree that this state of transition can be harsh but that is the price one must pay to get clean. 

Problem #3: Ketosis

Burning body fat instead of carbohydrate for fuel is known as ketosis and whilst it produces the obvious benefits of weight loss it puts additional burden on your kidneys and liver and in extreme cases causes serious damage. Milder side effects of ketosis are bad breath, a metallic taste in your mouth and strong urine odour.

This is true. Precisely speaking, first there is ketogenesis (the process by which the ketone bodies are produced; completely normal) and then, if certain circumstances occur, ketosis (a state of an elevated level of ketone bodies; still safe if not prolonged). It is worth mentioning that ketosis is nothing to be afraid of unless you are having some serious problems with your kidneys or liver.

If not sure, always consult your doctor before approaching the diet. Not every dieter will accept the mild side effects in form of bad breath or odd taste in his / her mouth. If you can’t live with it for a couple of days the diet is not for you. But when you experience one of the them, you know at least what is going on (the message is: “fat is being burned!“). More on ketogenesis, ketosis and ketoacidosis here.

Problem #4: Nutritional Deficiency

The Attack and Cruise phases of the Diet are very restrictive and if you have a lot of weight to lose you would be on this restrictive diet for some time. You can of course counteract deficiencies by the use of nutritional supplements (…)

If you are overweight or obese it is very likely that you are experiencing nutritional deficiencies right now (not even being aware of that fact). Truth be told, all the foods on a 100 Dukan Diet safe list are very nourishing and healthy. There’s an example of a few foods that are diet compliant and rich in minerals here.

Problem #5: Not suitable for everyone

There are a number of groups of people who would find it difficult or who would not be able to follow this plan. For example it is not suitable for Vegans or Vegetarians and the use of oat bran means than Celiacs (Coelaics) can’t follow this plan. It would also not be suitable for anyone who is pregnant or who has liver or kidney problems.

Abstracting from vegans and vegetarians who, in my opinion, shouldn’t have any problems with their weight (as their way of living is supposed to be nature-friendly)… Sure this diet is not everyone but which one is?

Why would a pregnant woman think of dropping any weight? Is there a weight loss program that is suitable for pregnant women?

As far as the presence of gluten in oat bran is concerned, Celiacs can substitute oat bran with rice bran which is gluten-free.

No one says that dukan Diet is for everyone. It is not. There is not a single diet that would satisfy everybody’s needs. ‘Not suitable for everyone’ is not a problem, it’s a factor that makes me believe that the Dukan Diet is a working method. In my view dukan Diet is not an impractical fad diet but it is a real, healthy diet plan for people who seriously think about losing weight.

Problem #6: Additional costs

I completely disagree with this:

Eating a diet high in protein but low in carbohydrates is more expensive. You can keep costs down by concentrating on eating eggs, poultry and milk products as your forms of protein but if you are going to be on the diet for any length of time you will need the variety that eating meat, fish and seafood will provide. There is also the cost of nutritional supplements to take into consideration.

Starchy food like potatoes, bread, corn, pasta is cheap indeed. On the other hand, after some time on the dukan diet the body adapts to more nourishing food and the fact is the overall amount of food you eat per meal is decreasing. Every dieter should keep in mind that it was most likely too much food that caused his or her overweight problems in the first place. ‘Quality over quantity’ is the key.

There are no supplements (in means of pills and such) recommended on the dukan diet. The diet’s 100 safe foods list consists of natural, easily available foods + oat bran. Everything else (i.e. vitamin tablets or diet coke) is voluntary and, most likely, won’t improve your results anyway.

Problem #7: The impact on your social life

The restrictive nature of the Attack and Cruise phases are likely to mean that you will need to make considerable changes to your social life.

Can’t argue with that. On the other hand, consider the impact your new, slim, and perfect body will have on your social life. Health and social problems are the two most common reasons to diet. I believe, that people who decide to go on with the Dukan Diet are counting on it to have an impact on their social life! They want to be slimmer, lighter, healthier and so on…

I know that some people would like to party, drink alcohol, eat sweets etc. and still lose weight, be healthy and feel great. You know what? This is not going to happen. You will not lose even a grain by just reading this text…


  1. Duka diet works perfectly for me… I tried it a few years ago, lost about 11 kilos… here I am doing it again, lost 4 kilos in the first 20 days… all people need to do is balance their intake of food… you do not need to eat 2 whole chickens, I mean half a chicken for lunch will do, a couple of eggs in the morning and fat-free Greek yoghurt in the evening, reduce your stomach size by downsizing your portions, or else you will end up going to square one in no time!

  2. I did Keto for four months (and that was hard!) and lost like 15 pounds, imop I think this duran diet is even more restrictave with all the rules and would drive me batty and make me smack mt head on the kitchen wall! So thank you for the info as I was curious about it.

  3. Hi. I’m on day 5 of the attack phase and have lost a total of 6.5 lbs. I meant to reach my goal weight in three months but I’m so motivated, I know I can do it! This site has given me great ideas to help deal with sweet cravings. My problem is that I was constipated for the first three days. I had a cup of coffee with Stevia yesterday and have had very loose bowels every since. I’m concerned that this isn’t due to just that one cup of coffee but can’t find any stats on diarrhea as a side effect of the Dukan Diet. I’m still taking 1.5 tbsp. of Oat Bran per day but it’s not binding me. Hoping the Cruise phase, which I start tomorrow, does the trick but am worried the opposite will happen due to the veg fiber. Has anyone experienced similar symptoms? I’m drinking lots of water to counter the loose stools but am staying clear of the coffee for now.

  4. It was mentioned that headaches could occur and that water intake is really important..
    Hint – darker urine snd a strong odour should be a warning. As a retired nurse I knew this with the high protein intake.. but… I am now taking two glasses with me at bedtime and I complete them by morning with my pain meds and BP meds.
    The aim is to lose weight & get OFF my BP pills but degenerative spondylosis of the neck (medically retired in Sep 2012) will remain with me and.. continue … so, exercise is picking up as much as I can and after Rupturing my left Anterior Cruciate Ligament , plus a sublaxing R shoulder (dislocated very inconveniently), I have stuff to do!
    Two HuskyXMalamutes to exercise, little cruiser to maintain .. I have to pick up – at 65 it doesn’t come particularly easy… so carry on everyone –
    “If it’s got to be, it’s up to me” !

  5. Today is day 3, I’m rarely hungry even though I’m still on the attack phase .ii have started the diet with an Apple a day I know I shouldn’t but I still did and I’m losing over a pound a day,my secret,I’m keeping my calories intake under 1500 calories.
    After many years of failed diets I found what works for me. I’m very active,on my feet walking all only complaint is diarrhea. I had headaches but feeling better.
    My goal is 40 pounds loss, I should reach it by July 9-2016, so excited.

  6. I have been on the attack phase for 4 days now and have lost 11.5 lbs. I am only looking to lose 20-25 lbs. Not sure if this is normal for so much.

  7. Hi,

    I started the dukan diet 5 days ago, i completed the attack phase with no issues and lost 6 pounds, my weight when starting was 9st 3 and im 22, i only wanted to loose that 6 pounds and no more, would i be ok just eating a normal healthy diet from today? Weetabix in the morning, Meat and veg for dinner and tea and fruit as a snack? or will it pile on me?? … dont want to risk it if it will just stick to me? Panicking.. Please help

  8. I’m following Dukan diet for about 3 months and up to now I lost 13 kg (plus other 5 that I lost before starting the diet). The diet is going well and together with sport 3 times per week and I lose in average 1 kg per week. So as per the calculation I should follow the diet for another 6-7 weeks to reach my true weight.

    However the since 1 month I started to have increasing daily stomach problems like permanent diarrhea, bloating and flatulence and very unpleasant noises done by my stomach especially at work (however I should mention that there is no pain). I’ve tried almost anything like reducing diary intake up to zero (one day I ate only meat and I still had problems), removing Goji bear and Cola Zero from my diet partially and then completely, but the situation does not get better. If I take pills against diarrhea and bloating I’m feeling better but as soon as I stop this comes back, so I can’t eat pills as additional food for such a long time.

    I already started to be seriously worried and I’m not sure if I should continue with my diet or to stop it. My doctor recommended to stop the diet and eat for couple of days plain boiled rice, old bread, boiled carrots and bananas but I’m afraid of the effect that this will have on my weight.

    Does any of you had any advice for me? Did any of you got these kind of problems?

    1. Simona,
      I’ve done dukan and lost 60lbs and have remained for over 3 years now. I have made it my life style.
      First off, even though Dr. Dukan permits having sugar substitutes, I never did, I just cut sugar out. If I really, really craved sugar, I just had a small amount of honey or sugar. NO Substitutes. Our stomach has really hard time processing it. I think the problem you’re having is you’re not eating enough mixed foods. For example, I had oat bran with every meal, in different forms, as well as protein and vegetables. There are plenty of recipe’s on pintrest, on google just mix it up. Plus, don’t forget about water, drink half your body weight in ounces. All other beverages are not as necessary.
      This has helped me a whole lot.

    2. Hi
      I’d recommend Kefir yoghurt as a top probiotic that won’t cost a lot (£0.98/L) from Polish shops, large Tescos.
      I had this just before I suddenly had gastroenteritis (GP informed me a virus was going round) & whilst I dropped 4lbs in 32 hours (gained 2lb after symptoms ceased) I did lose that 4lbs by day three.
      Look at what your eating..
      I like my oat bran with Kefir added after cooking, and I use semiskimmed milk. Just into my 3rd week start and 13lbs off.
      Yes .. I enjoyed a 4 square section of a chocolate & nut bar! .. but boy, I really enjoyed it .. then back onto Cruise phase. I’ve 20 lbs to go however I may aim a bit further if I can regain back to a size 14 (from an uncomfortable 18)..
      I was a chubby 10-12 yr old then grew 6″ in my 13th yr and became almost anorexic looking.
      Third pregnacy two years after my second in my 42nd year finally caught me up (incl third LSCS).
      Why not ‘break for a bit.. then resume… ?

  9. Hi, I have been on the Dukan since June 3rd, I lost 10 KG and i cheated last week with a doughnut and follwed by 2 PP days and today i had another brownie, i feel terrible, what should I do?

  10. Following the diet for two weeks have gone down about 6 and 1/2 pounds. I did the attack phase for 1 and 1/2 days …all I could stand. I am eating low fat proteins etc. with green drinks made in my blender so I get fiber. I love the idea of all 0 fat dairy products. I made a tasty canoli like filling using stevia and vanilla. I also used fat free sugar free jello to get over rough spots. Most amazing is my fasting blood sugar this morning 77 and not 103 or 110. Is is due to omission of wheat, sugar and lower fat content. I will continue this way of eating indefinitely since I know my triggers. It is a brain saving diet as well as far as I’m concerned ….looking forward to checking my A!C level in a couple of months. (68 years old)

    1. hi can u please tell me what u have in your green in your blender, it sounds really good to me, also the stevia and vanilla? What is that?
      Thank you

  11. I just found this site. What a great place with all the information in one spot. I started the DD October 2012 by jan 2013 I had lost 20 kg or 44lbs. I thinks for me the oat bran and the daily walking was it. I got within 6 lbs of my goal and didn’t stay at it. Now I have gained 6 lbs so I an starting for phase 1 today . I do and will continue to walk every day. The way I feel now compared to last summer if no comparison .

  12. Hi
    I have been on the diet for 2 weeks .

    I am eating fat free greek yougart, with fruit bits , this reads it has sugur in 13g per 100g is this ok to eat ??? I m eating 100 g per day ??

  13. I have been on the Dukan diet for 2 months and lost only 6.9 kg. I thought by now I would have lost more that 10 kg. I still have 49 kg to go and are losing hope because according to the website will only lose 39 kg up to 13/10/13. It feels like lightyears away! Do other people also lose weight this slow or am I doing something wrong? I also have a craving for fruit, what do I do about that? Thanks

  14. Whats going on no replys been on diet coming up to 6 mnths only lost 12kg
    should be at ideal weight by now and been strickt pls comment

  15. My colleague and I just started this diet 3 days ago. He has lost 4 lbs and I think I may have gained 1. It could be the scale (I am buying a new one tomorrow) but I was wondering if it might be the nonfat plain and nonfat flavored vanilla yogurt. He’s not a yogurt fan, I love dairy and it’s helping me to get all the meat down. I know they are in the “unrestricted” list on the attack phase but all the non fat yogurts still have sugars. Do you think this is the problem or should I just be patient? Someone told me today that if I’m eating even nonfat yogurt, then I’ve eliminated all the benefits bc my body will not get into a ketosis state.

    Help bc I feel like I wasted 3 days :(

    1. It’s true. It’s very unlikely to get into ketosis on yogurts only. Try eating less yogurts, more high protein dairy (like quark or non-fat Greek style yogurts that are packed with protein) and more lean meat. This should bring about some more encouraging effects.

  16. Hi after doing my attack phase and through the first week of the cruise I went Into hospital n diagnosed with Transverse myelitis, would this diet had triggerd anything as in short time is my immune system being over effectiant but attacked my spinal fluid instead of a virus. Also abandoning the diet for hospital food for a week can I resume from the cruise phase or do I need to start from the attack phase?

    1. You can resume from the cruise phase since PP sub-phase is basically the same thing as the attack phase. If you start the diet over you will probably get a better kick-starter. Also, consult your MD if you are having any health issues before doing anything radical to your eating habits.

      The dukan diet is a high-protein, low-carb diet that triggers ketogenic processes and acidify your body (especially during the attack phase). But these are pretty natural processes. I don’t know whether those processes can cause Transverse myelitis or unwanted immune reactions. By definition, no. Not in healthy people. Once again, you should ask your MD if there’s any risk of developing complications after starting the diet.

  17. I am on second day of Dukan diet. I dont crave sugar and dont feel hungry, but i dont have any energy. I have short of breath and has difficalties to walk on stairs. I dont know what to do. Someone recommended to add pinch of sugar to my tea. I have to do that, otherwise i am not able to do anything. I was on Dukan diet one year ago and was losing one pound a day. I stopped diet because I developped diarrhea. Any thoughts?

    1. There’s in fact plenty of sugar in plain yogurt or milk. I would suggest eating a tomato or even fruit yogurt instead of using pure white sugar. Sometimes this lack of energy and all can be more of psychological provenience than any real health issue. If you having any health issues consult your physician. Otherwise, it’s probably just an induction flu. It usually eases of after a few days.

  18. Just started the Dukan its my second day and I have the flu but I am confident and optimistic after reading this article and other peoples comments here : )

    I was recently diagnosed with PCOS so hope this helps with the weight loss.

    Current weight: 9st 9lbs
    Ideal: 7st (one hopes)

    Thank you all

  19. There’s one thing I want to mention about Gout. First, I suppose I should tell you why I want to mention this. I worked for a while in the weight loss industry myself (I won’t mention where, just that the programs we offered were also high in protein), and we had some restrictions when it came to people who already had Gout, as it could cause sudden flare ups of the condition. Notice I said COULD cause.

    So, with that said, I would encourage anyone who alread has Gout to be cautious when doing this diet as well, because from what I understand, Gout flare ups are not to be trifled with.

    Other than that, this site is great! Thanks so much for providing this wealth of knowledge =)

    1. Thanks for your opinion. It’s nice to hear from a person with hands-on experience in a weight loss industry environment. You are right. People with ANY health issues should always consult their doctors before changing anything in their lives (including dieting etc.)

  20. I started the DD on Nov. 2, 2011 & as of Dec. 26 I am down 14 lbs. I have 4 lbs to go to be at the weight that was suggested according to my profile & to begin phase 3. This was the easiest weight loss I’ve ever encountered, incorporated with moderate exercise 3 times a week. The funny thing is that I even cheated here & there allowing myself a few cocktails on weekends (vodka & club soda w/lime.) I am 46 & have never felt better. The steady weight loss is extreme motivation for me to stay on task.

  21. I started my diet on May 2nd and lost 30 lbs in 10 weeks and lost an additional 10 lbs in stage 3 of the plan. I found it easy. I was never hungry. The weight came off fast and I never felt deprived. I will be done on December 16th.
    I never had a headache, I was never constipated, I never felt “flu-like”, I did not have bad breath, etc….I feel fabulous and was excited every single day to weigh myself and see the success!!! GO FOR IT!!!

  22. Thank you for taking the time to explain everything and links to where we can look in to things like this. I have been on the diet strictly for 3 weeks. I am 5’10” and male. I have went from 222lbs to 206lbs in 3 weeks. My goal weight is 196 according to the official website. My actual goal strangely enough was 195. I have had no side effects whatsoever with the exception of non regular bowel movements however even those are becoming more regular (When starting they were about every 4 days. They are now about every 2-3 days). As mentioned in this article I am/was a big eater. Some things to know about me: I am a salad hater, don’t like egg yolks. I love sweets, potatoes, soups of all kind, chips, steak sauce and pretty much anything with sugar in it. My work also buys lunch for everyone pretty much every day from various places chosen by them. I have also been on other diets that were recommended by doctors and they turned out horribly. Anything from cold soups to counting calories although I did lose weight counting calories it wasn’t nearly as fast as the dukan diet and it sucked to have to look at every thing I was eating to see if I supassed my calories.

    Some notes to know about on this diet.
    1. You will make a huge adjustment in your eating habits and I am not going to say that it is easy. About the hardest thing on this diet for me is not knowing at the exact time whether I can eat something or not.

    2. You can eat as much as you want!!! Damn!!! This is my kind of diet. As I stated I am a big eater. I started out in the attack phase and could not get full. As much as I tried I would ALWAYS be hungry. My wife brought home and cooked me a Fred Flinstone Brontasaurus Steak… This thing was huge! I ate the whole thing and 15 minutes later I was hungry again so I ate two Huge tubs of salad… that’s right I said salad… this was not a small bowl. This was a big mixing bowl of salad that she made me, twice. That was during the first couple of days of phase 2. Since then as mentioned in this article I am down to about a half a mixing bowl’s worth of salad and it fills me up for a good portion of the day. I have not had steak in 2 weeks. I eat low sodium turkey which tastes damn good. I eat low sodium roast beef which surprisingly is also damn good. So while it is true that during the initial phases of this diet you will eat a lot more than you are used to it is also true that the eating will slow down. I have had people hand me kit kats and brownies and the desire is still there to eat them but not nearly as strong as it was 2 weeks ago.

    3. During the initial couple of weeks on this diet I got really sick of eating turkey and roast beef every day. OMG! However, I went to and looked at other people using the diet in the forum. There are not a massive amount but there is enough recipes there to make your life more interesting. They give you what you need to utilize in those recipes. Google search the items because they do not give you where they got them. My wife and I just ordered a bunch of stuff from Nature’s hollow. We are not sure whether it will work yet but it should be here next week.

    4. The diet is working for me is all I can say. I have 10 more pounds to lose before I hit phase 3. I am sure that those will be gone within the next 2 weeks.

    1. Great job on changing your eating habits. The diet did the same thing for me. I make a dessert out of Non-fat Greek Yogurt, and Butterscotch Fat Free, Sugar Free Pudding. Mix it together with two cups of Yogurt and you have one heck of a dessert and it cools those sweet cravings. Best of luck with your last 10lbs

  23. i was on the Dukan Attack phase for 5 days then went out with friends and had pizza, crisps, chocolates all weekend. I am now back on the attack phase and have been in this phase for 4 days and in total have lost 5lbs in two weeks. My question is that I have had the flu with a really bad headache since being on this diet. Its been 2 weeks and i feel weak, bunged up, tired and my headache will not go away, is there anything you can suggest? are my symptoms connected to the dukan diet? I do drink at least 1.5l of water every day. Would really appreciate some advice?


    1. First, visit your doctor and make sure you’re not ill. If it’s not real flu, just move on to the Phase II PV and see whether that change will relileve the flu-like symptoms or aggravate them. If the symptoms develop go to a doctor.

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