Health, Nutrition, Podcast

Low-carb high-fat (LCHF) for endurance sports with professor Tim Noakes | EP#44

 July 27, 2017

By  Mikael Eriksson

Low-carb high-fat (LCHF) for endurance sports with professor Tim Noakes

Low-carb high-fat (LCHF) for endurance sports with professor Tim Noakes

In part 2 of our interview with professor Tim Noakes we discuss low-carb high-fat diets and the role it can play both for general health and endurance performance.

In this Episode you'll learn about:

  • The relation between high-carbohydrate diets and diabetes
  • How Tim ran the same times aged 61 as 41 when switching to a low-carb diet
  • Tim’s take on ketogenic diets


How did you get into low-carb high-fat (LCHF) diets?​

02:25 -

  • ​I advocated a high-carbohydrate diet for 33 years. One day I opened my email and there was an ad for a book called The New Atkins for a New You written by Dr. Westman, Jeff Volek and Stephen Phinney. They claimed that you could lose weight on a high-fat diet (The Atkins Diet). I said, well we know that’s false because if you eat saturated fat, you’re going to die of a heart attack.
  • But then I thought, they are good scientists. I knew their work on high fat diets. I knew Stephen Phinney was a first-class scientist. So I said, there’s a paradox here. I must give them the benefit of the doubt.
  • So I bought and read the book and within two hours I said, “Oh my gosh, I got it all wrong for 33 years.” They listed 150 studies of low-carbohydrate diets and the health benefits, and the fact that your performance was not necessarily worsened on a high-fat diet.
  • Back in 1970 when I was running marathons, we would go on a high-fat no-carbohydrate diet on days six, five, four before the marathon and we would feel terrible. And then for the last three, two, one days before the race, we would load up on carbohydrates. Initially, I ran well on this but gradually I just got worse and worse and it didn’t help my performance. And the reason was, I was insulin resistant, I was resistant to carbohydrates.
    • Note: These are ofte referred to as carb depletion and carb loading phases.
  • I went on this LCHF diet and literally my running time went back to what they had been when I was 41 (I’m currently 61). All the impairment I had between 40 and 60 which I thought was because I was just getting old was nonsense. It was because I was eating this bad diet - too much carbohydrate in someone who is pre-diabetic and then ultimately diabetic.
  • Then I started reading solidly for 5-6 years. I read hundreds of books and tens of thousands of articles. It all makes sense that humans evolve as fat burners. We hunted animals for their fat not for their protein. Particularly in the countries in northern Europe, we lived on mammoths because they had so much fat in them.
  • Humans have got a limit to how much protein they can consume. We can only provide 35-40% of our calories from protein.
  • Then I started getting reports from people who are using the LCHF diet.
    • One of them is a lady I helped, Paula Newby Fraser who is recognized as perhaps the greatest triathlete of all time. She’s a South African who went to America when she realized she had a real talent. She won her 1st triathlon, a short distance triathlon, without training. Then she trained for a month and came 3rd or 4th in Hawaii in her first year. In 1984, just when Steve Phinney published his first paper showing that a high-fat diet may help athletes in endurance sports, she asked me what I think about it. I told her that she should try it. After that, she  When she retired she told me that the best advice she ever received in her life was the advice I gave her to try the LCHF-diet. She cut the carbs and ate a low-carb diet for all the years that she was successful.
    • So did Mark Allen. The key to both of them was that they had long careers. Both of them had low-carb diets.
  • If you’re eating all that carbohydrate - especially that refined junk that people justify that they can eat because they’re athletes - it harms you and your health. Your body gets inflamed, you don’t recover, and there might be all sorts of complications.
  • In talking about high-fat diet, we focus rather too much on the acute effect in the laboratory. If you go on a high-fat diet for three weeks, will your performance improve? This is actually not the question. The question is, what happens if you eat a high-fat diet for your career? Do you race more often? Do you have more successful races? Do you last longer? Do you have fewer injuries? These are the questions that the athletes are finding out for themselves.
  • I think the evidence is coming through that the elite athletes are adopting this diet. Chris Froome (who just recently won the Tour de France again - Mikael's note) converted to a low carb diet, lost 8 kilograms and started to win races and never looked back. This doesn’t mean that he will not take carbohydrates on races and events, he probably had a lot of carbs last night, and he will take carbs during the race. But it doesn’t mean either that on the other days that are not so demanding that he will load up on carbs to the same extent. And particularly in the off-season, he will not be touching carbs.

Did you lose a lot of weight between the age of 41 and 61 when you were running the same times and you had a high-fat diet?

10:43 -

  • I lost about 6 kilos in the first 6 weeks. I eventually lost 20 kilos. All of my running gains were achieved within 6 weeks long before I lost all the weight.
  • Chris Froome is the best example. He couldn’t win the Tour when he was 8 kilograms heavier. But he dropped the 8 kilos and he became the world’s best cyclist.
  • My increase in performance happened between 4-6 weeks. Suddenly after 4 weeks I started running much better. And within 2 weeks I achieved a lot of that benefit. In my case, there was a metabolic change that happened in my body.
  • For people like myself who are insulin resistant, when you cut the carbs, you get a huge metabolic advantage even without the weight loss.

Who would you say that this LCHF diet is for? Is it for the everyday athlete even if you’re not necessarily insulin-resistant or have Type II diabetes?

13:41 -

  • Firstly, if you’re eating a high carb diet, it is a nutrient-poor diet. That is what we’re not told. If your diet is based on grains and cereals, it is nutrient-poor.​
  • High-nutrient diets come from high-fat diets from animal produce. If you want to really get a nutritious diet, this is what you have to eat.
  • An example, one of the guys that I have converted recently is now one of the top Ironman triathletes in South Africa. He converted and after 16 weeks did his best Ironman, running 2-3 minutes faster than ever for the marathon. I asked him what he was eating before. He told me he was eating chocolates and sweets, coke, and chips. I told him that these were nutrient poor and how can he expect his body to succeed on this diet. He said, but it’s carbs. I told him, those are rubbish, those are nutrient poor. As soon as he converted, he improved.
  • So I think this is the 1st problem that the highly processed foods that we eat, that we are encouraged to eat are not good food. So everyone needs to get rid of these foods regardless if you’re insulin resistant or not.
  • Let’s make a point that the majority of the people are insulin resistant. The further north you come from, the more insulin resistant you are because your predecessors lived on woolly mammoths.
  • The Catarvans in the South Pacific eat a 70% carb diet, and they are profoundly insulin sensitive. But you go one island away to Australia, and you will find that the Aborigines there are very insulin resistant. Or the Indians in North America who lived on bison, they’re profoundly insulin resistant. And as soon as you give them this rubbish diet, this processed industrial diet, they become obese, diabetic, and within one generation their health is utterly destroyed.
  • In my own town, they did a study of a thousand people and every single one of them is diabetic or pre-diabetic. In northern European countries, they're much less prone to get sick on this diet than other populations who have never seen grains for most of their evolutionary history.
  • It depends on the population, but it’s generally 50-60% of people that's insulin-resistant.
  • My best advice is no one should know what their cholesterol is because it is utterly meaningless.
  • But if you’ve got what you call Glycated hemoglobin value (HbA_1c), this tells you what your average glucose is during the day for the last 3 months.
  • If your value is more than 5.5%, you’re eating too much carbs and you need to cut down. You must be below 5.5% for optimum health. If it’s more than 5.5%, you will develop diabetes in a matter of time.
  • What is going to make your diabetes come in more quickly is eating a high-carb diet because the running or triathlon is not going to prevent it from happening.

Key takeaway

  • Have your HbA_1c-value measured.
  • Make sure it's below 5.5% by not eating too much carbs.

What is your take on new technologies that can monitor blood glucose levels in real time? What value do they provide?

19:44 -

  • I know there’s one coming out from Apple and Tim Cook (Apple's CEO) has been wearing it for the past few months. And he lost 20 lbs. when he was using this device, because he started noticing that when he ate carbs his glucose shot through the roof.​
  • What people need to understand is that chronic ill health happens every time you spike your insulin or glucose. And every time you eat carbs, your insulin shoots up.
  • The key to longevity is to keep your insulin and glucose as low as possible which you can’t do on a high-carb diet.

What’s your opinion on using LCHF or ketosis to lose weight in order to get your racing weight?

22:03 -​

  • If you have a weight problem then you’re eating too much carbohydrate. So it’s a simple solution.​
  • What you need to understand is that you can’t exercise to lose weight.
  • If you’re 3 kilograms heavier than what you should be, then your diet is wrong, your diet is a problem. And I think this is the problem because we talk about "calories in and calories out". So people say, "the only reason I’m 3 kilograms heavier is because I’m not doing that much exercise." No, you’re eating more calories than you need because they are all carb calories and you don’t need them, you’re insulin resistant, and you’re not burning those carbs. So what’s happening is, you’ve increased your carb intake more than what you need, you’re storing the carb as fat, and you’re getting hungry. This is the key.
  • Obesity or weight gain is a problem of hunger. It’s not a problem of not doing enough exercise. And we as exercise physiologists, completely made that error and the industry wants us to continue making this error. Industry wants us to keep saying, ‘guys, you can eat these refined carbs as long as you do your triathlonw and train 2 hours a day.’
  • But the reality is that you don’t need to have that extra weight. It just tells us that your diet is wrong and you must fix your diet first.
  • So that athlete who has put on 3 kg during the rest period is eating too much carbs. So cut down the carbs and the 3 kg will disappear. Then you’ll understand that this is not a calories in, calories out issue, it’s an issue of hunger, insulin resistance and too much insulin.

Does ketosis have any additional benefits? What role does ketosis and ketogenic diets play in this whole picture?

24:56 -

  • There’s some really good studies coming from Oxford last year showing that if you ingest ketones, your performance seems to go up.​
  • I’m less sure that we need to do this for the majority. I think this is a very expensive intervention.
  • Also, the other thing is that I think if you do take external ketones or if you are ketogenic, the ketones might be acting in the brain as much as anything else. So the performance benefits might be due to a brain effect.
  • I’m just not convinced that adding more fuel to the body during exercise is going to improve one’s performance.
  • However, there’s also evidence that ketones does other things: they may enhance immune function, they may improve mitochondrial biogenesis.
  • I think that we’re still not there to understand the full role of ketogenic diet for athletic performance. I think that one of the problem for many of us is it’s very difficult to stay in intense ketosis. The dietary changes are quite tough.
  • However, for example, you really have to eat a very low-protein high-fat diet to be in ketosis all the time. I think that people need to experiment for themselves and see what happens if they’re in ketosis and see whether they really need to be in advanced ketosis.

Rapid-fire questions

27:53 -

​Favorite book, blog or resource related to nutrition, psychology or endurance sports:

Personal habit that helped you achieve success:

  • Physical activity particularly running ultra-marathons​
  • With effort, belief, and hard work, you can do things you couldn’t believe

What you wish you had known or done differently at some point in your career:

  • I wish I had known about this LCHF diet when I was 15 or 16​.

The Noakes Foundation

31:36 -

  • We formed The Noakes Foundation from the money we raised from the book Real Meal Revolution.​
  • At the moment, I put a lot of my effort to help promote the idea that you can actually eat very well, even the poorest people.
  • We are about to start a network for promoting the teaching of this diet for doctors.

Links and resources

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Mikael Eriksson

I am a full-time triathlon coach, founder of Scientific Triathlon, and host of the top-rated podcast That Triathlon Show. I am from Finland but live in Lisbon, Portugal.

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