Sunday, October 24, 2010

Carbohydrate Intake and Depression

It's hard to know where to start on this one.  Everywhere you look, if you look, you see surprisingly consistent correlations between carbohydrate intake and depression.  Some studies draw a direct link.  Others find strong correlations with certain long-term results of high carbohydrate consumption, such as insulin resistance (see here also), diabetes (and here), vitamin D deficiency (and here), obesity and so on.  Some of these, and many others, make the leap to causation and successfully attempt to treat depression by correcting specific deficiencies or excesses.  Still others observe a relationship between low-fat diets (independent of carbohydrate intake) and depression.

After a lot of searching, I managed to find a single study investigating the effects of a ketogenic diet on depression in humans.  Its loneliness in the literature was not lost on its author:

It is surprising, after so much clinical experience spanning a period of two thousand years, that this paper is the first [and last] by a psychiatrist describing the applications of the ketogenic diet in the treatment of anxiety, depression, and dysperception. Meanwhile, throughout this most advanced society of ours, in every modern psychiatric facility patients are exposed to an overdose of carbohydrates... It is time that the application of available knowledge in this field should be the rule rather than the exception. Ignorance and fear of controversy are no longer an excuse to withhold this basic and physiologically-oriented treatment from our patients.

In addition, there is one other study, perhaps better designed and conducted than the one above, observing similar results from the same treatment, but in rats.  The near-absence in medical literature of what looks like a pretty obvious conclusion, given the evidence, is disappointing and almost surprising.  There's no shortage of informal discussion in online forums, blogs and so forth about this phenomenon, but serious treatment is conspicuously scarce in peer-reviewed medical journals.

All the available evidence seems to point to dietary carbohydrates as the major causal factor in endogenous depression, but the specific reasons are elusive.  As you might expect, all this is really complicated.  For example, reducing dietary carbohydrates almost necessarily means increasing intake of something else, usually fat.  It also means reducing serum insulin levels, losing weight, and a pile of other things, any or all of which might be relevant to depression.  So do carbohydrates directly cause depression?  Is it the insulin secreted in response to elevated blood sugar from carby meals?  Is it the lack of dietary fat in high-carbohydrate diets, as suggested here?  The lack of vitamin D?  Is it caused by insulin resistance, diabetes, obesity? 

Some of these ideas can apparently be ruled out in at least some cases, but the entire body of available evidence speaks with a single voice: either directly or indirectly, increases in carbohydrate intake increase both the risk and severity of depression with remarkable consistency.  Given that, we would expect - and we do find - that reducing carbohydrate intake has the opposite effect.  Taken to its logical conclusion, these facts suggest that a ketogenic diet would be a fantastically effective treatment for depression.  Very little research has been done to confirm this, but what is available appears to be a strong confirmation of everything else we know.

Conclusion: dietary carbohydrates are the major cause of clinical depression, and a ketogenic diet presents itself as an ideal treatment.


  1. Hi Rocco, I have to say it feels a bit of stretch to make it to your me the links to double blinded studies confirming carbs as the culprits and it would seem less like "new math". There are so many endocrinologic processes involved in digestion let alone neurotransmission it's hard to imagine that carbohydrates(glucose) are totally evil. That being said I think the FDA is bought and paid for by Pfizer et al and I definitely don't think the corn or potato industry cares about anything aside from the bottom line. Terri

  2. Terri, Maybe I wasn't as clear as I'd hoped, that I didn't think carbs were directly the culprit, mostly for the reasons you mentioned. There's obviously a great deal of complexity, especially endocrinological complexity, in the long chain of events between carbohydrate metabolism and neurological changes. But it does seem to me, from the evidence I've cited, that there's a very clear link between high-carbohydrate diets and depression, and similar links between other conditions associated with such a diet, and depression. Which process is ultimately to blame is anyone's guess at this point, but the root cause does seem to be high-carbohydrate diets.

  3. I once read "Carbohydrate Addicted Kids" and it definitely put the blame on carbs for ADD and ADHD, which have to do with your neurotransmitters. After seeing my grandson off of carbs for a week, I became a believer. I have no doubt that carbs can cause depression, anxiety, and probably most all of the other psychological problems. You won't hear that on the news though!

  4. Gee, Rocco, when's the next post??????

  5. I have taken anti depressants for 19 years now and recently felt like I would need to increase the dose as I felt lower than I had ever felt before (apart from the time I initially started taking them).

    Two days ago (unaware of the carb/depression connection) I commenced a low carb diet in order to loose weight. My spirits and energy levels have risen so much so that I wondered if any research had been done and found this web site. There has to be a link.

  6. Thanks so much for the comment! I hope it continues to work for you, and good luck with the weight loss!

  7. I just finished "Good Calories, Bad Calories", by Gary Taubes (writer for SCIENCE magazine). Great read. I'd recommend it for anyone who really wants to delve into all the studies done regarding hyperinsulinemia and all the other things that have been shown to be a result of processed carb intake. It's a loooooong book, but you won't come away from it with the same misconceptions about dietary fat/cholesterol = HBP/Heart Disease/Obesity that you've been spoon-fed all your life. It's truly uplifting. : )

  8. I too am day 23 into a lower carb diet (almost no sugar, no flour etc) and I have noticed a dramatic decrease in anxiety and depression (I have been on them for 15 years) I made the dietary change to drop an extra 15 pounds I have been carrying, as my recent cholesterol panel was a little higher than the "optimal" that I had been used to. I am a physician, and also noted the paucity of literature looking at low carb diets and anxiety/depression. It certainly could be placebo effect, but I am planning to start weaning my antidepressants in the near future to see what happens.

  9. Well I started a diet 3 months ago, No carbs no sugars and very little to no food with hours of exercise I have droped 38 pounds .Just about 2 weeks a go my body woke up in a panic thinking I was fainting and having a heart attack at this point the nerves were not letting me eat cause I kept wanting to vomit all the food so I just would not eat ..... I went 4 times to the emergency room and did EKG's blood work it was horrible I felt like I was dying it was something out of this world crying anxiety fear chills so much pain internal and external it was horrible my head wanted to burst ... Well all my blood work came back ok and kg potassium was good wasn't anemic and they just weren't able to figure out my horrible change , the night was even worst my body would go into complete shock of anxiety ..... :( through lots of prayer I finally got the answer god told me to look up no carbs and anxiety and well guess what my problem is ..... My body is going thru shock from not eating any carbs I just recently started to eat them even if I feel like vomiting I know that its from the nervousness but it won't go away untill I eat a lil carbs and my body recognises the carb I'm my body

  10. Hey you're not supposed to starve yourself. Of course your body's going to freak out. Almost every time I hear something like this, somebody's not eating carbs *and* not eating enough fat.

  11. This is great!

    My husband and I have had few roller coaster years emotionally. We are ok, it has just been problems with some of those around us as well as some life events. We both have high stress jobs, and we have 2 kids approaching college. We both are 50 years old, had gained weight and have felt drained of energy and interest in life, beyond making sure we meet our basic obligations.

    We decided to try a high protein, low carb diet. In past dieting life, I have always focused on getting most of my calories from protein as that is what has always worked for me. My husband has never dieted in his life. He saw an aquaintance who had lost 60 pound quickly on a low-carb, high protein diet and came home and asked me if we could try that.

    I did a little research on line and settle on the Dukan Diet. We are 6 weeks into it. I have losted 15 pounds and he has lost 21. But most profoundly is the low-grade depression that has dragged us down the last couple of years is gone. We both have more energy and are motivated to tackle issues, projects, tasks that we had procrastinated about in our low-energy, low-grade depressed state of mind.

    I decided to research online to see if there had been any established connection with high carb diets and depression. There may not be a lot of research on this, but I will tell you it is true! I have had periods in my life when I have gone in and out of this low grade depression. Eventually over time I get back to baseline. This has been such a dramatic improvement I cannot deny the connection.

    I will say also that exercise has been important for me as well. And I am only talking that I make sure I walk 20-30 minutues 3-4 times a week. This has been important, but it was really the high protein diet that pulled us out of the depression.

  12. Hi Rob,
    Your blog is so informative and uplifting. I became a believer in the low carb diet when I read Taubes' GCBC in July of this year. Thank you for speaking the truth.

  13. Hi Rocco - Sorry about addressing you as Rob in my previous comment.

  14. I have suffered anxiety for ten years. my wife was on a low carb diet and lost a lot of weight so i followed suit. My anxiety went away within maybe 5 days.

    No whenever i eat a big carb meal like large chips it will return within about 12 hours...then goes away when i resume the low card diet.

    The link is like clockwork for me. It is just so predictable. I googled carb n depression and found so many links. why is the mainstream media not talking about this?


  15. Same reason mainstream academia isn't talking about it, is my guess. It's out of line with heart disease dogma among other things. I read a PubMed article not long ago where they found evidence a ketogenic diet could stop the progression of Alzheimer's but concluded they'll just have to find a drug that produces the same effects, since everybody knows the diet will just kill them with heart disease.

  16. Hello Rocco,
    Thanks for sharing this important information. I am wondering if you have noticed a distinction in your studies (as relating to effects on depression) between the ketogenic diet (which limits protein as well as carbs) and a diet such as Atkins (or others) that encourage high protein, fat, and fiber content. I'm not sure if the availability of protein for conversion would limit the necessity of the increased mitochondria production by neurons? Thanks, Rika

  17. Well a ketogenic diet doesn't by definition limit protein. If you're prescribed one by a doctor it may be protein-limited, but it's really just a diet that puts you in ketosis, and you can eat all the protein you want and achieve that, as long as you avoid digestible carbohydrates.

  18. I have been on (and off) and low carb diet since Oct. When I go off and start eating more carbs, it has seemed to me that I got depressed and irritable. And when I reduced the carb intake, it seemed that I felt better and the depression went away. I have noticed this cycle several times. I googled it and found this site. I personally think there is something to the carbs causing depression, at least for me.

  19. Rocco; No joke this is 100% true. I did my own test on myself by accident when I was trying a ketonic diet. When it happened to me after eating a large bowl of fruit I started looking up carbs & depression to see if I was imagioning things and I found your article.

  20. Hello everyone.

    hey Rocco , first of all i would like to thank you for your well written article and everybody here for sharing their experiences.

    I have recently started a low carbohydrate diet because i have restarted SSRI treatment.
    (I stopped due to severe weight gain )
    which i believe , was from giving in to the strong carb cravings i have only whilst on A/D medication that work. (the A/Ds that did not work did not increase my carb cravings go figure)

    Anyway , back to the low carb diet i started about one week ago.

    I have been moderately discouraged by articles (speculating ?) that low carb diets decrease mood and are a bad for people that suffer from depression.
    A simple web search will show you what i mean.

    Anyway this article including the above comments have motivated me to keep on with my low carb diet (ALREADY lost 5kg in 1 week) and give it a chance.

    I Feel that i shouldn't discuss my mood , because i started the A/D's and low carbing simultaneously not long ago.

    Sorry for dragging on , but this is really important for me and i need all the motivation i can get.

  21. Thanks for commenting Chris, and I hope this helps you get rid of those meds!

  22. I've been on a low carb diet for a little over a year now. I am 54 years old and suffered with depression all my life.. even with meds there was never much of a difference. About 6 months ago I began a NOTICABLE difference in my mood when occasion arose where carbs were consumed. I was not just staring at the giant black hole of depression.. I dove right in and started swimming in it! I am also hypothyroid. Bouts of serious depression will certainly ensue soon after consumption of carbs. I have learned that they are poison to my mood. I have also learned that exercise and fish oil will help lessen the effects of carbs on my mood but will continue to avoid them. There may not be a great deal of medical studies done in regard to this but then again, I don't need a medical study to explain why it hurts if I burn myself, go figure. I'm very glad that there are others that have experienced the same result as I have.

  23. I would like to say that from my perspective as a constantly depressed individual that reducing food intake helps my depression. This ketabolic state increases my mood. Two things I've picked up over this course of my depression were nicotine usage which caused the lack of appetite. The smoking temporarily helped but once I reached this ketabolic state I feel better, with of without the smoking.

  24. I just did 7 weeks of the Primal Blueprint, which I had to stop because I got nausea, loss of appetite, coldness, complete loss of energy, and severe depression. I started adding carbs back and felt better immediately and my appetite came back.

    I am very confused about this. For me, carbs are making depression go away.

  25. I've seen this happen to people who try to do this while also avoiding fat in their diets. You absolutely *must* eat plenty of fat, particularly animal fat, to avoid this unpleasant and unhealthy outcome. I mention it here:

  26. I can tell you, I went on the Primal Blueprint in February this year and have lost nearly 40 pounds and managed to fight my way through some pretty nasty life events without getting deeply depressed.

    Well, a few weeks ago I started to worry about the animal fat/heart disease link and started cutting back the fat. I started to slowly feel worse and worse. Then I realized I was not getting enough calories without the carbs AND fat in my diet. So then I started to supplement with more fruit, and some unrefined carbs such as potatoes and rice. I felt great again, but noticed the extra carbs made me crave them more and more to the point where, for the past week, I have been eating pizza,ice cream, etc. Well, the depression just slammed me this week. Wow.

    I am still not convinced it is the "carbs" that cause the depression, but rather the sugar and refined wheat products. I felt good while eating "clean" carbs like rice, potatoes, and fruit. But it did make it harder to not overeat.


  27. I stumbled across this blog after a quick search looking for a scientific link between ketogenesis and depression.
    I made a huge decision 11 months ago to stop all meds for my PMD (Major Depression with Psychosis). I found they were turning me into a cabbage (!) and I wan't prepared to be like that for the rest of my life. So I began looking for alternatives. After wading through some amount of crap pop psychology, I finally hit upon the concept that food could be the answer.
    After much trial and error, I can tell you that accidentally stumbling across the idea of ketogenesis to improve depression, has given me a massively better quality of life....without meds (!)
    I'm astounded that it took all my perseverence to firstly find this solution and secondly, that there are not unlimited amounts of studies showing the same.
    Do the pharmaceutical companies not want us to know that a simple diet change will fix the problems?
    Some people might do well on a little carbs and sugars, but in my experience, my best success came when I stuck meticulously to the modified Atkins.
    Pain in the a__ at first, but the results are like winning the big prize in the lottery. It's all I've ever wanted.
    Consequently, I have also discovered that people who are having trouble with infertility (me), may benefit from ketogenesis. Variable blood sugars apparently contribute hugely to infertility. So, please keep your fingers X'd for me that the diet helps that too :)
    Thanks for this artical. I wish everybody here every success in finding their answer to their depression.....but definitely give ketogenesis a try....a real, sincere try.
    Good luck x

  28. Thank you for this post! I am suffering from depression and crave for carbs...Didn't know that those things were connected before. Now I'm going to try to reduce my carbs intake (and increase fat intake) and see how it affects my depression.

  29. I suffer from a severe and debilitating depression and anxiety.. more than a month ago I started on the ketogenic diet with a personal trainer for sport and weight loss, one major side effect- -the depression has lifted. Im happy, I smile, I laugh.

    Yesterday and today Ive had a higher carb intake because of a cyling challenge,the challenge was easy, but the crash has been killer, ive been crying since we finished, i have those thoughts of being worthless and better off dead.. its not easy to eat a ketogenic diet everyday.. but It is my proof that its totally worth the effort..

  30. I love low carb and ketosis lifestyle - it definitely helps my mood ( suffered from depression since I was a teen and used anti-depressants for years). But one thing I notice on low carb - it's super important to eat enough fat (cream, butter, olive oil, fat on meat, etc). And it's important to eat enough, period. Today I ran out of groceries so I ate far too light of a supper. All too often if people are really gung ho about weight loss, they don't eat enough and that's just not good for our moods. Note to self. Buy groceries tomorrow.