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Continued: Tim Noakes on the diabetic diet

If you haven’t read Part 1 of this blog post, please click here – this second part will make much more sense if you do!

This is Professor Tim Noakes’ opinion on diabetes and eating protein and carbohydrate – continued from yesterday’s post. If you have any questions for Prof. Noakes, please post them here and we’ll ask him for you when we interview him for the next issue of Sweet Life.
So I discovered that the foundation of the “prudent diet” begins in the head of one man – an American biochemist, Dr Ancel Keys, in the early 1950s. Ten years earlier he had convinced the US Military to adopt his unproven food combination – the K(eys) rations – to replace what for centuries had become established as the ideal food for troops on the move – pemmican, a mixture of protein and fat made from the bison – the staple food of the American Plains Indians before the intrusion of the white man, who shot out their bison and forced them onto “reservations”.   The evidence is that when eating bison, the Plains Indians were the tallest and healthiest of all human populations.  Today they are amongst the least healthy with rates of obesity and diabetes second only to those found in the Pacific Islanders.

Infatuated by this success, Keys next set out on an even more daring escapade – the quest to change the eating behaviours of the entire Western world.   He would convert the world to his belief that a high fat diet was the singular cause of ill health, especially heart disease, in all humans.  This ran contrary to more than 100 years of an alternative wisdom that it is the carbohydrate content of the diet that causes both obesity and diabetes – two established precursors of heart disease.

Within a short time Ancel Keys achieved his goal of demonizing fat as the exclusive dietary cause of heart disease and as a consequence of all human ill-health.  By 1977 the first US Dietary Guidelines were published – these emphasized the need to restrict the intake of “artery-clogging” fats and in their stead to eat “heart healthy” carbohydrates. 

Thus began the single greatest nutritional trial in human history – within a few years, the foodstuffs highest in the two key constituents that humans had become adapted to through 1-2 million years of our evolution – fat and protein – were replaced with those – novel sources of carbohydrate especially grains and cereals – to which we humans have been exposed for less than 1% of our entire existence.

Now three decades into this trial, it is perhaps time to take stock of what has been the outcome of this remarkable trial.   The answer is what we might call the “elephant in the room” that everyone wishes to ignore. It is the rampant increase in the prevalence of obesity and adult-onset diabetes, most especially in North America and some European countries, to the point where in 20 years time the cost of treating adult-onset diabetes will bankrupt the medical services of the United States and Great Britain.  Importantly this increase in the prevalence of diabetes and obesity has occurred as Americans have adopted the key elements of the “prudent diet” – the intake of carbohydrates in North America has increased progressively over the past 3 decades whereas the consumption of especially saturated fat and meat has fallen to the lowest levels in one hundred years.

Next I reviewed both the scientific and popular literature which shows, at least to me, that the only one way to reduce my risk for developing adult-onset diabetes is to minimize my daily carbohydrate intake of carbohydrates.  A wealth of scientific studies have shown that, by reducing the amount of glucose produced by the liver in diabetics and by increasing disposal of glucose into body storage sites, a carbohydrate-restricted diet dramatically improves glucose control.  As a result, the need for insulin falls dramatically.   Thus I learned that a  carbohydrate-restricted diet would reduce the stress on my pancreas and my arteries (as a result of better glucose control) thereby hopefully allowing me to avoid the development of full-blown diabetes for some time yet.

As predicted by these findings, my adoption of a high fat/moderate protein/ very low carbohydrate diet has produced encouraging improvements in all my blood markers of pre-diabetes and in all those blood cholesterol parameters considered, incorrectly I believe, to predict risk of heart attack.  So in contrast to the conventional wisdom but in keeping with all the published literature, my blood cholesterol parameters are now much “healthier” on a high fat diet than they were a year ago when I was following the supposedly “heart healthy” high carbohydrate diet.    

More importantly my weight has fallen by 15kg; I have dropped my running time in 21km races by more than 40 minutes so that I am now aiming to break 50 minutes for 10km (at age 62); I again have the energy that I remember in my twenties, and I am no longer hungry.  Instead I now eat only when the thought strikes me that it would be a good idea to have something to eat.  I interpret this as evidence that I have returned to a primal state when we ate in order to live and not the reverse.  This absence of hunger has taught me that carbohydrates, especially refined carbohydrates, are addictive in that, in those like myself, they stimulate over-eating, progressive weight gain, increasing lethargy and ultimately the onset of adult-onset diabetes.

I appreciate that many of my colleagues who manage diabetes do not agree that a low carbohydrate diet should be prescribed for those with either Type I or Type II diabetes.

All I can report is that, as a pre-diabetic, I have tried both a high carbohydrate and a low carbohydrate diet.  The one clearly exacerbated my condition; the other has been associated with a dramatic improvement in my quality of life and in all my biomarkers of metabolic and cardiovascular health.  

The decision of what I should eat is therefore, at least for me, very simple.

Written by Professor Timothy Noakes OMS, MBChB, MD, DSc, PhD (hc), FACSM, FFSEM (UK).
Discovery Health Professor of Exercise and Sports Science at the University of Cape Town and the Sports Science Institute of South Africa.

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  1. I have tried this diet for a month. My mood is worse, my energy stores are lower and my wish for training are less because I feel tired. I reckon the low carbohydrate diet can be good for few and that’s all. We can not think this diet is going to work, french, italian and asians eat carbohydrate everyday and they are not among the countries with the highest obesity rates.

  2. Hi Bridget & Team

    What about kidney health when following a low carb, high protein diet? Please ask Prof Tim Noaks to explain a little on a condition called “ketosis” that occurs when following a high protein diet where the body consumes its own muscle fibres.
    Should one not include at least a little low GI carbs with every meal to counter this? To look at what they call the glycaemic load.



    • I also wonder about that, Nanette – I’ll definitely ask him, thanks!

  3. Alison Alison


    I am following this debate with interest. I have always been interested in nutrition and the more I read the more confused I get – who do you believe when there are so many conflicting ideas? What has happened to the old fashioned idea of a ‘balanced diet’ where a moderate portion of all the food groups seemed to be the most logical choice.
    As I am married to an Italian, it seems impossible to consider giving up pasta altogether. I would love to hear Prof Noakes’ comments on the Italian and French diets, where pasta and bread are fundamental. They don’t seem to suffer from diabetes and heart disease as much as we do in this country and in the USA. Has it more to do with the amount of sugar that they eat? They do eat pastries but do not seem to have the same sweet tooth that many of us have in this country. I guess, my final question is, it seems so extreme to cut carbohydrates out of out diet completely, can this be correct?
    Thank you and look forward to reading his answers next month.

  4. Tim Noakes Tim Noakes

    Pablo’s response is unusual. There is an addictive component to a high carbohydrate diet especially one containing a lot of sugar, and removing that addiction can cause some to develop “withdrawal” symptoms for some time after adopting this diet. But the key question is: Did your glucose control improve on this diet? If it did, then your health has to be better. In time your brain will also adapt and you will feel better.

    Kidney disease in diabetes is caused by poor glucose control and perhaps fructose-induced kidney damage (as discovered by Richard Johnson MD and described in the New England Journal of Medicine). A low carbohydrate diet improves glucose control in diabetes and removes excessive fructose from the diet. Thus a low carbohydrate diet should improve renal function in diabetics with poor glucose control and high fructose intakes (in the form of sugar and sweet fruits). There is no evidence that the increased protein intake on this diet can produce kidney damage.

    Ketosis is a crucial state for diabetics to exploit. There is now good evidence that high carbohydrate diets induce what is known at Type III diabetes or Altzheimer’s disease, in which the brain cells becomes resistant to the action of insulin. As a result the brains of persons with Altzheimer’s disease become increasingly less able to utilize glucose as a fuel for brain function. Persons with diabetes are at increased risk (2x) for the development of Altzheimer’s disease. The way to reduce the risk for developing Altzheimer’s disease is to reduce the fluctuations in glucose/insulin that occur in response to repeated ingestion of high carbohydrate meals (requiring insulin injection). Ketones are the optimum brain fuel in all because they do not require insulin for their use by the brain. Thus ketones are able to cover all the brain’s energy needs and are essential for continued brain health in Altzheimer’s disease.

    The difference between the physiological ketosis produced by a high fat diet is that blood ketone levels rise to a maximum of 4mmol/L (in those who have some insulin secretion) but to 40mmol/L in those with diabetic ketoacidosis who become totally insulin deficient (but which does not occur in those who have some capacity to produce even a little insulin). This is a quite different condition from the state of physiological ketosis produced by a high fat diet (in those who still have the capacity to produce some insulin).

    There is a difference between what causes diabetes to occur and what to do when one has the condition. The evidence is that high sucrose (fructose) intake (in susceptible individuals) is probably very important in the production of diabetes. This is what the epidemiological evidence shows – populations begin to develop Type-II diabetes about 20 years after sugar is first introduced into the community. Classic South African examples are the Zulu and Indian populations in Durban and, in Israel, the Yemeni Jews. In all these populations the incidence of diabetes began to rise dramatically 20 years after each was first exposed to sugar at an intake of more than about 50 grams a day.

    Once diabetes has happened the question becomes, in my view, what diet produces the best glucose control and best maintains the markers of sustained good health.

    That is what the debate should be about.

  5. I have type 2 diabetes which was diagnosed some ten years ago, For the past 9 years I have only been on small dosage of Glucophage, unfortunately in the last six months my sugar reading has gone up above 10 > and is climbing, I have tried everything, different foods and yes most the high carb one’s. This would include low fat yogarts, high fibre GL cereal, GL seeded bread and it does not seem to help, My G.P recommended that I follow the Tim Noaks diet, which I have started today 12 June 2014. Will keep you posted how it works.

    • Please do, Gyfford! Best of luck with it…

  6. Desre Desre


    I have heard so much about this diet but i cannot afford to buy the book as for reasons of long unemployment.

    is there any way that Mr Noakes would assist me with an e copy?

    I have about 45 kg to loose and I have heard really good things about this diet.

    Much obliged


  7. Miemie Miemie

    Hi, my friend developed diabetes after a traumatic car accident some years ago. He started on the Noakes diet around September and have lost a significant amount of weight, he no longer takes any medication and have his blood glucose tested at work from time to time, the last reading was 0.5. He no eats a meal a day consisting of either eggs or tuna as he say he no longer gets hungry. I have however noticed a change in his moods the last two weeks and last Sunday he looked like someone who was heavily intoxicated and even spoke with a slur. I know for a fact that he did not consume any alcohol. How does the diet fall in the eating regime of a diabetic and should he be taking his medication as normal?

    • Hi Miemie,
      His reading couldn’t be 0.5 or he wouldn’t still be standing! That does sound worrying, though… Has he been to see a doctor at all? Does he only eat one meal a day, and no carbs whatsoever? That could be dangerous… Please let us know.

  8. Henko Henko

    Im a type 1 diabetic and i inject myself at a average of 5x a day…..
    Im very lean not fat at all.. Should i go on his diet or not coz me and my family started with his diet 2weeks ago and since then my blood sugar does not go under 10??? How is that possible ?? And i eat good portions without any carbs…
    Please help..????

    • Hello!
      I don’t think the diet works for everyone, Henko. I’m also a lean Type 1 diabetic and when I interviewed Prof Noakes he said it applies to about 60% of diabetics, and if you’re healthy and lean on a diet that contains carbs then obviously your body can process them. This was a few years back, but I don’t think his stance on that would have changed. The bottom line is: do what’s good for you and your blood sugar!

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