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The Case for Keto by Gary Taubes… my thoughts
A thread
https://optimisingnutrition.com/the-case-for-keto-by-gary-taubes-my-thoughts/
A thread
https://optimisingnutrition.com/the-case-for-keto-by-gary-taubes-my-thoughts/
After recently publishing Big Fat Keto Lies ( https://www.bigfatketolies.com/big-fat-keto-lies), a number of people asked me what I thought of Gary Taubes’ new book The Case for Keto ( https://www.amazon.com.au/Case-Keto-Rethinking-Practice-Low-Carb-ebook/dp/B07XXFHP9S).
I have just finished writing a book on most common misconceptions and mistakes in low carb and ‘ketogenic’ diets through the lens of Nutritional Optimisation (listed below), so I had a few thoughts.
- Keto Lie #1: ‘Optimal ketosis’ is a goal. More ketones are better.
- Keto Lie #2: You have to be ‘in ketosis’ to burn fat.
- Keto Lie #3: You should eat more fat to burn more body fat.
- Keto Lie #4: Protein should be avoided due to gluconeogenesis.
- Keto Lie #2: You have to be ‘in ketosis’ to burn fat.
- Keto Lie #3: You should eat more fat to burn more body fat.
- Keto Lie #4: Protein should be avoided due to gluconeogenesis.
- Keto Lie #5: Fat is a 'free food' because it doesn’t elicit an insulin response.
- Keto Lie #6: Food quality is not important. It’s all about insulin and avoiding carbs.
- Keto Lie #7: Fasting for longer is better.
- Keto Lie #8: ‘Insulin toxicity’ is enemy #1.
- Keto Lie #6: Food quality is not important. It’s all about insulin and avoiding carbs.
- Keto Lie #7: Fasting for longer is better.
- Keto Lie #8: ‘Insulin toxicity’ is enemy #1.
- Keto Lie #9: Calories don’t count.
- Keto Lie #10: Stable blood sugars will lead to fat loss.
- Keto Lie #11: You should ‘eat fat to satiety’ to lose body fat.
- Keto Lie #12: If in doubt, keep calm and keto on.
Here is my critical review.
- Keto Lie #10: Stable blood sugars will lead to fat loss.
- Keto Lie #11: You should ‘eat fat to satiety’ to lose body fat.
- Keto Lie #12: If in doubt, keep calm and keto on.
Here is my critical review.
The good
Firstly, you have to give Taubes credit for doggedly advancing the case for the low carb diet ever since he wrote The New York Times article What if It’s All Been a Big Fat Lie? ( https://www.nytimes.com/2002/07/07/magazine/what-if-it-s-all-been-a-big-fat-lie.html) back in 2002.
Firstly, you have to give Taubes credit for doggedly advancing the case for the low carb diet ever since he wrote The New York Times article What if It’s All Been a Big Fat Lie? ( https://www.nytimes.com/2002/07/07/magazine/what-if-it-s-all-been-a-big-fat-lie.html) back in 2002.
Many people, including my wife Monica, who lives with Type 1 Diabetes, have benefited from the low carb and keto movements who have made a lower-carb diet a more acceptable approach.
In 2011, Taubes wrote Why We Get Fat: And What to Do About It ( https://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259), which has shaped the thinking of the low carb and keto movement immensely.
Then, in 2017, after many people pointed out that there were plenty of populations thriving on a low-fat high-carb diet, Gary wrote The Case Against Sugar ( https://www.amazon.com/Case-Against-Sugar-Gary-Taubes/dp/0307701646), painting sugar as dietary villain #1.
And now, we have The Case For Keto ( https://www.amazon.com.au/Case-Keto-Rethinking-Practice-Low-Carb-ebook/dp/B07XXFHP9S).
Taubes’ research
Taubes, along with Peter Attia, has been instrumental in asking the questions and assembling the funding to, through their Nutritional Science Initiative ( https://nusi.org/ ), ask and investigate some of the most interesting and important questions in nutrition and…
…metabolism.
However, sadly, it seems that, in spite of the learnings from valuable studies he has instigated, his thinking hasn’t changed much since 2002.
Taubes is an investigative journalist who tells meticulously detailed and engaging stories that cast doubt on mainstream dietary recommendations.
If you are a low carb or keto proponent who wants your current beliefs reaffirmed with more of what you have loved from Gary in the past, you will love this book.
But, unfortunately, it doesn’t do much to progress the science of nutrition.
But, unfortunately, it doesn’t do much to progress the science of nutrition.
To quote Taubes, “This book is a work of journalism masquerading as a self-help book.”
The Title: The Case For KETO
The first problem I have with “The Case for Keto” is the title.
To be fair though, it’s not Gary’s fault.
Taubes has admitted that the title was the publisher’s idea to jump on the keto trend.
The first problem I have with “The Case for Keto” is the title.
To be fair though, it’s not Gary’s fault.
Taubes has admitted that the title was the publisher’s idea to jump on the keto trend.
Although the popularity of ‘keto’ has been in decline for the past two years, it still far outstrips low carb, Atkins and many other popular diet trends/fads.
So ‘The Case for Keto’ it makes sense, from a marketing perspective, given that keto is so hot right now.
So ‘The Case for Keto’ it makes sense, from a marketing perspective, given that keto is so hot right now.
Ironically, Taubes mentioned in his Diet Doctor interview () that he originally wanted to call the book ‘In Praise of Fad Diets’ after being interviewed on why fad diet books were so popular.
He had the epiphany that fad diet books are popular because people are always in search of an alternative to the conventional advice.
This book is written to the sceptics who would like to believe that they ‘fatten easily’ and they are fat and/or diabetic because the mainstream nutritional advice is wrong.
Later, the working title for the book became ‘How to Think About How to Eat’. When the publisher suggested The Case For Keto Gary said it ‘gave him the willies’. But it seems to have stuck regardless.
Taubes obviously doesn’t think there is much of a difference between low carb and keto. He said, ‘I don’t know when it became keto. It used to be Atkins, but you couldn’t write another book on Atkins’ because it had already been done.’
This book is really about the benefits of a lower carb Atkins style diet (not keto)
While Taubes doesn’t seem to differentiate between low carb, Atkins, nutritional keto and therapeutic keto, The Case for Keto is primarily the story of low carb and Atkins with some fear of insulin and protein thrown in.
As a journalist, Taubes tells the history of the previous successful versions of lower-carb diets including Atkins ( https://en.wikipedia.org/wiki/Atkins_diet), Jean Anthemele Brillat-Savarin’s 1825 The Physiology of Taste ( https://www.penguinrandomhouse.com/books/18327/the-physiology-of-taste-by-jean-anthelme-brillat-savarin-translated-by-mfk-fisher-introduction-by-bill-buford/) and William Banting’s Letter on Corpulence…
…( https://www.gutenberg.org/files/57545/57545-h/57545-h.htm). While you are reading a book titled The Case for Keto, these previous historical success stories are not really ‘keto’.
Although he does not say it (or perhaps even realise it), the book is arguing the case for a diet with less refined carbohydrate and a focus on protein.
‘Keto’ has an identity crisis!
One of the problems that I have with ‘keto’ the word means so many things to so many people.
The term has become polarising and effectively meaningless.
One of the problems that I have with ‘keto’ the word means so many things to so many people.
The term has become polarising and effectively meaningless.
While this is great for selling (fad?) diet books to a broad audience, the lack of precision often leads to confusion, stalled progress, and sadly, worsening metabolic health.
What is a ‘ketogenic diet’ anyway?
The most commonly accepted definition of a ‘ketogenic diet’ is one that generates ketones greater than 0.5 mmol/L ( https://www.dietdoctor.com/lose-weight-by-achieving-optimal-ketosis).
The most commonly accepted definition of a ‘ketogenic diet’ is one that generates ketones greater than 0.5 mmol/L ( https://www.dietdoctor.com/lose-weight-by-achieving-optimal-ketosis).
Many people believe that ‘optimal’ (i.e. better?) ketosis occurs at higher levels. This often referenced chart from Phinney and Volek’s Art and Science of Low Carbohydrate Living ( https://lowcarbdownunder.com.au/shop/the-art-and-science-of-low-carbohydrate-living/) shows that the ‘optimal ketone zone’ is between 1.5 and 3.0 mmol/L.
The classical or therapeutic ketogenic diet ( https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6361831/) was developed early last century to treat kids with epilepsy.
Extended fasting was found to control epileptic symptoms, but rather than long term starvation, a more viable and sustainable solution was to increase the fat (while keeping carbs and protein very low) in the diet to the point that blood ketones became elevated.
In order to keep ketones elevated, a classical ketogenic diet typically consists of 80-90% fat ( https://www.epilepsy.com/learn/treating-seizures-and-epilepsy/dietary-therapies/ketogenic-diet#:~:text=the%20ketogenic%20diet%3F-,The%20%22classic%22%20ketogenic%20diet%20is%20a%20special%20high%2Dfat,do%20not%20respond%20to%20medications.). A ketogenic diet also tends to help people manage symptoms of Parkinson’s, Alzheimer’s and dementia.
This is wonderful for people who require a ketogenic diet. However, the vast majority of people who come to keto are not doing it for Parkinson’s, epilepsy, dementia or Alzheimer’s control - they want weight loss, diabetes reversal and improved metabolic health.
Exogenous versus endogenous ketosis - the important differentiation!
The confusion comes when we observe that the body also can produce ketones from our body fat, particularly in the initial phases of weight loss.
The confusion comes when we observe that the body also can produce ketones from our body fat, particularly in the initial phases of weight loss.
We can produce ketones endogenously (from our stored body fat that we want to lose) or exogenously (from extra dietary fat or exogenous ketone supplements).
Sadly, the differentiation between exogenous ketosis and endogenous ketosis is very rarely made. People just assume that elevated ketones are magical, regardless of where they are coming from.
If you follow this logic, then:
If you follow this logic, then:
- Ketones are good.
- More is better.
- Keto is the end goal.
- More is better.
- Keto is the end goal.
What seems to be missed is that the appropriate dietary prescription for endogenous ketosis versus exogenous ketones is radically different. This distinction is critical, particularly if you want to lose fat from your body and improve your metabolic health.
Ketones are transient
Back in the day, followers of the Atkins diet used urine ketone test strips ( http://www.doingatkins.com/ketostix.html ) during the induction phase to confirm that they were doing the diet right and they were ‘in ketosis’.
However, it was acknowledged that this initial ketosis period was transient. After a while, your body would adapt and no longer spill ketones into the urine.
With the creation of widely available (although still expensive) blood ketone testing (created for people with Type 1 Diabetes to check for diabetic ketoacidosis ( https://www.diabetesaustralia.com.au/living-with-diabetes/managing-your-diabetes/ketoacidosis/)), testing ketones has become more popular.
They were deemed the ‘gold standard for measuring ketosis ( https://keto-mojo.com/en-au/article/testing-for-ketosis-difference-between-blood-breath-urine/)’.
I had the privilege of having Professor Steve Phinney (pictured below in our kitchen) stay at our place when he spoke at a Low Carb Down Under event in Brisbane in 2016.
I had the privilege of having Professor Steve Phinney (pictured below in our kitchen) stay at our place when he spoke at a Low Carb Down Under event in Brisbane in 2016.
While I had him as a captive audience for a couple of day, I quizzed him about the basis of his 'optimal ketosis' chart.
Steve said the chart was based on the blood ketone levels of participants in two studies done in the 1980s. The first was with cyclists who had adapted to ketosis over a period of 6 weeks.
The second ( http://europepmc.org/article/MED/7000826) was a weight loss study where people were put on a ketogenic diet.
The critical thing to note is that, in both cases, ‘optimal ketone levels’ (i.e. between 1.5 and 3.0 mmol/L) were observed in people who had recently transitioned to a lower-carb or ketogenic diet.
As more people have ‘gone keto’, many people find that their blood ketone levels continue to decrease after a few weeks or months (even though they are still following a 'ketogenic diet').
We now know that, over time, ketone levels in our blood decrease as we become more metabolically healthy (i.e. lower blood sugars, lower body fat, lower waist:height ratio).
Most people move beyond the ‘keto-adaptation phase’ as their bodies learn to use fat more efficiently in the citric acid cycle rather than ketosis (which you can think of as a backup pathway in times of starvation).
As they reduce body fat levels they are able to store excess energy from their diet in their adipose tissue and their ketone levels reduce even further.
Interestingly, the Inuit, who are often used as an example of people who thrive on a very low carb diet, have a genetic adaptation, so they see even lower levels of ketones on a high-fat diet.
Perhaps our bodies don’t like to be perpetually ‘in ketosis’ which is a less efficient way of burning fat compared to the default citric acid cycle when there is adequate oxaloacetate from protein and carbs?
This leaves many people faced with the decision to either:
This leaves many people faced with the decision to either:
- continue to add more refined fat (e.g. butter, MCT oil, exogenous ketones etc.) to maintain ‘optimal ketosis’, or
- reduce dietary fat to allow fat from their body to be used, thus improving their metabolic health, reversing their diabetes and reducing or obliterating obesity.
- reduce dietary fat to allow fat from their body to be used, thus improving their metabolic health, reversing their diabetes and reducing or obliterating obesity.
Should ‘keto’ be the end goal?
The chart below shows the sum of the blood sugar and ketones (i.e. total energy) from nearly 3,000 data points from a broad range of people who say they are following a low-carb or ketogenic diet.
Blood ketones are shown in blue (on the bottom) while glucose is shown in orange (on the top).
On the right-hand side of the chart, we have a high energy state where both glucose and ketones are elevated at the same time.
While some people have high ketones and low blood glucose (likely endogenous ketosis), there are also some people with high glucose and high ketones together (likely exogenous ketosis, from high levels of dietary fat).
This high energy situation is similar to someone with untreated Type 1 Diabetes with high glucose and high ketone levels due to inadequate insulin - their stored energy flows into their bloodstream, and they see elevated levels of glucose, ketones and free fatty acids…
On the left-hand side of the chart, we see people with a lower total energy in their bloodstream. Because they store and use fuel efficiently, metabolically healthy people don’t need to have large amounts of glucose or ketones circulating in their bloodstream.
What happens to ketone levels on a 'ketogenic diet' over the long term?
It’s interesting to see how my crowd-sourced ketone data aligns with data from the Virta study one-year results (Phinney et al., 2017) ( http://diabetes.jmir.org/2017/1/e5/ ). The distribution of BHB levels after 10 weeks of the Virta trial are shown in the chart below.
Towards the right, we see that there were a few people with higher ketone values, many people also had values of less than 0.5 mmol/L, even during the initial adaptation phase.
Despite consuming a 'ketogenic diet' under the supervision of the Virta Team ( https://www.virtahealth.com/ ), most of the study participants did not achieve ketone levels that qualified as 'nutritional ketosis' (i.e. BHB > 0.5 mmol/L).
The next chart shows the average ketone levels from people participating in the Virta study over the first year (from Effectiveness and Safety of a Novel Care Model for the Management of Type 2 Diabetes at 1 Year: An Open-Label, Non-Randomized, Controlled Study…
We see that blood ketone levels initially rose from 0.18 mmol/L at baseline to 0.6 mmol/L in the first few weeks. But from there, blood ketone values decreased to 0.27 mmol/L after a year. This is well below the minimum threshold for nutritional ketosis (i.e.
BHB > 0.5 mmol/L), let alone the ‘optimal ketone zone’ (BHB > 1.5 mmol/L).
As shown in the chart using data from Virta’s study 2-year results (Long-Term Effects of a Novel Continuous Remote Care Intervention Including Nutritional Ketosis for the Management of Type 2 Diabetes: A 2-Year Non-randomized Clinical Trial ( https://pubmed.ncbi.nlm.nih.gov/31231311/ )), blood…
…ketone levels remained at 0.27 mmol/L after 2 years of a 'ketogenic diet' as people continued to lose weight and improve their diabetes. I am looking forward to seeing the three year results from the Virta trial. I image that ketone values will stay stable or even decrease.
We have seen a similar trend with ketones in our Nutrient Optimiser Masterclass ( https://optimisingnutrition.com/6-week-nutritional-optimisation-masterclass/). Blood ketones tend to rise for a couple of weeks when people focus on high satiety nutrient-dense meals ( https://app.optimisingnutrition.com/sales-page1589026225015).
But after a few weeks, blood ketone levels decreased as people continued to lose weight and lowered their blood sugars.
If you are on a ketogenic diet, relatively metabolically healthy and lean and not overdoing the refined dietary fats, you may see BHB ketone values between 0.3 and 1.5 mmol/L.
Ketones will be higher if you are fasting, restricting calories, exercising or consuming more dietary fat. But keep in mind that blood ketones will likely decrease over time as your metabolic health improves.
Many people conclude that being concerned about blood ketones is not worth the expense, pain and hassle.
OK. That’s enough pedantic ranting about ‘keto’. Obviously, I think it’s an important and much-maligned topic.
I fear that a book called ‘The Case for Keto’ will inspire another surge of people chasing elevated blood ketones and then drinking butter and MCT oil to keep them high over the longer term (which is where I was five years ago when the photo on the left was taken).
I’ll move onto some of the other elements of ‘The Case for Keto’ that frustrated me.
Will I get fat if I eat carbs?
Taubes firmly believes that carbs (which raise insulin more in the short term) are the dietary devil.
He says:
Taubes firmly believes that carbs (which raise insulin more in the short term) are the dietary devil.
He says:
The culprits, specifically, are sugars, grains and starchy vegetables. For those who fatten easily, these carbohydrates are the reason they do.
I’m not going to make the case for nutrient-poor refined carbohydrates, but it’s worth highlighting that, at least since 1999 when artificial sweeteners were approved by the FDA, obesity has NOT tracked with carbohydrate intake.
When sugar intake started to decline in 1999 and was replaced by synthetic sweeteners, obesity continued to climb. This divergence in the data should cast some doubt on carb and/or sugars as being the only culprit in our growing waistlines and worsening metabolic health.
Nutrient poor refined sugar is not a health food and does convert to fat in the liver, but it is not the only piece to the obesity puzzle.
Taubes should know that a high carb diet doesn’t necessarily make people fat.
The part NuSI-funded year-long DIETFITS study with more than 609 participants (Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial…
…( https://jamanetwork.com/journals/jama/fullarticle/2673150)) found that (regardless of genetics, insulin levels or blood sugars), participants following either the low-fat or low-carb diet achieved similar weight loss and improvements in metabolic health.
The researchers initially encouraged participants to pursue a diet as low in carbs or fat as they could achieve and then back off to a level that they thought was sustainable for the long term.
As you can see from the comparison charts below, both the low fat and the low carb arm lost a similar amount of weight.
The key observations from the DIETFITS study ( https://drruscio.com/high-carb-low-carb-science-actually-says-episode-43/) were as follows.
The key observations from the DIETFITS study ( https://drruscio.com/high-carb-low-carb-science-actually-says-episode-43/) were as follows.
- Following either a low-carb or low-fat diet can help to reduce the hyperpalatable, highly processed junk food in our diets that typically causes us to eat more than we need to.
- Over time, most people gravitate back to hyperpalatable junk food (which is typically a combination of nutrient-poor fats and carbs together).
- It was the people that changed their DIET QUALITY who had the most significant long-term success. These people experienced increased satiety ( https://optimisingnutrition.com/calculating-satiety/) and no longer felt like slaves to their appetite.
Lead researcher Professor Chris Gardner ( https://profiles.stanford.edu/christopher-gardner) stated that, rather than pursuing a magic macronutrient ratio, defining diet quality in a way that leads to satiety ( https://optimisingnutrition.com/calculating-satiety/) is the next exciting frontier of nutritional science.
The fat+carb danger zone
Speaking of satiety, the chart below is from our analysis of 587,187 days of food logging ( https://optimisingnutrition.com/calculating-satiety/). The vertical axis shows the reported daily calorie intake in MyFitnessPal divided by the users' target calorie intake.
The rest of this thread can be read here: https://optimisingnutrition.com/the-case-for-keto-by-gary-taubes-my-thoughts/
