Keto Diet Theory Put to the Test

Keto Diet Theory Put to the Test

“Keto Diet Theory Put to the Test” When you don’t eat
enough carbohydrates, you force your body to burn more fat. However, this rise in fat burning is often misconstrued as a greater rate of net fat mass
reduction on the body. But that ignores the fact
that on a ketogenic diet your fat intake shoots up as well. The question is what happens to
your overall body fat balance. You can’t empty a tub
by widening the drain if you’re cranking up the
faucet at the same time. Low-carb advocates
had a theory, though, the so-called carbohydrate–
insulin model of obesity. Proponents of low-carb diets,
whether a ketogenic diet or a more relaxed form of
carbohydrate restriction, suggested that the
decreased insulin secretion would lead to less fat storage; and so, even if you
were eating more fat, less of it would
stick to your frame. So, we’d be burning
more and storing less, the perfect combination for fat loss— or so the theory went. To their credit, instead of
just speculating about it, they decided to put
it to the test. Gary Taubes formed the
Nutrition Science Initiative to sponsor research to validate
the carbohydrate–insulin model. He’s the journalist who
wrote the controversial 2002 New York Times Magazine piece “What if It’s All
Been a Big Fat Lie,” which attempted to turn
nutrition dogma on its head by arguing in favor
of the Atkins diet with its bunless bacon cheeseburgers based on the carbohydrate–
insulin model. (Much of Nina Teicholz’s
book, “The Big Fat Surprise”, is simply recycled from
Taubes’s earlier work). In response, some of the very
researchers Taubes cited to support his thesis accused him
of twisting their words. “The article was incredibly
misleading,” one said, “I was horrified.” “He took this weird little idea and blew it up, and people
believed him,” said another. “What a disaster.” It doesn’t matter what people say, though. All that matters is the science. Taubes attracted $40 million
in committed funding for his Nutrition Science
Initiative to prove to the world, you could lose more body
fat on a ketogenic diet. They contracted
noted NIH researcher Kevin Hall to perform the study. Seventeen overweight men
were effectively locked in what’s called a metabolic
ward for two months to allow researchers total
control over their diets. For the first month they were placed on a typical high carbohydrate diet (50% carbohydrate; 35% fat; 15% protein), and then they were switched
to a low-carb ketogenic diet (only 5% of calories from carbohydrate;
80% fat) for the second month. Both diets had the same
number of daily calories. So, if a calorie is a calorie
when it comes to weight loss, then there should be no
difference in body fat loss on the regular diet
versus the ketogenic diet. If Taubes was right, though, if fat calories were
somehow less fattening, then body fat loss would
become accelerated. What happened instead,
in the very study funded by the Nutrition Science Initiative, was that body fat loss
slowed upon switching to the ketogenic diet. Wait…why do people
think the keto diet works if it’s actually slowing fat loss? Well, if you just looked at the
readings on their bathroom scales, the ketogenic diet would
seem like a smashing success. They went from losing
less than a pound a week on the regular diet in the two
weeks before they switched to losing three and a half
pounds within seven days after the switch to the ketogenic diet. But what was happening
inside their bodies told a totally different story. Their rate of body fat loss
was slowed by more than half. So, most of what they were
losing was just water weight. (The reason they started burning
less fat on a ketogenic diet was presumed to be because
without the preferred fuel, carbohydrates, their bodies started
burning more of its own protein.) And that’s exactly what happened. Switching to a ketogenic diet
made them lose less fat mass and more fat-free mass;
they lost more lean mass. That may help explain why the
leg muscles of CrossFit trainees placed on a ketogenic diet may
shrink as much as 8 percent. The vastus lateralis is your
biggest quads muscle in your leg, shrunk in thickness by
8% on a ketogenic diet Yes, the study subjects
started burning more fat on the ketogenic diet, but they
were also eating so much more fat on the ketogenic diet that they
ended up retaining more fat in their body despite
the lower insulin levels. This is “diametrically opposite”
to what the keto crowd predicted, and this from the guy they
paid to support their theory. In science-speak, the
carbohydrate–insulin model “failed experimental interrogation.” In light of this “experimental
falsification” of the low-carb theory, the Nutrition Science Initiative
effectively collapsed…. but, based on their tax returns,
not before Taubes and his co-founder personally pocketed millions
of dollars in compensation.


  1. This is the 2nd in a 7-video series on keto diets. In case you missed the first one, check out Is Keto an Effective Cancer-Fighting Diet? ( and subscribe to the video feed to get them in your inbox ( -NF Team

  2. Reading these comments is depressing, people need to step away from tribal “us vs them” mentalities when discussing science and something as important as the health of billions of people. I would like to point out that the Am J Clin Nut 2016 study is far too small to draw any major conclusions from, it was just a pilot study. It does strongly support calorie restriction for overall fat loss though – which isn’t news, but keto and fasting supporters know how easy calorie restriction is on a low carb diet.

  3. So all of the 36 pounds I have lost over the last 6 mo the was just me losing water weight and lean muscle mass despite an increase of my strength while sinultaniously decreasing my body weight? My anecdotal evidence has shown different results for me as an individual.

  4. What about time-restricted diets?

    I eat breakfast at about 7AM, a snack and then dinner at 4PM, nothing else until breakfast. I didn't weigh myself but I did have to add more holes (three) to my belt as the inches melted. This was weight that I had been fighting for years. I'm 53 and had just given up thinking that I couldn't lose the weight because of my age. The diet as it had been before was pretty clean. No sodas, mostly water with low sugar intake. I did and still do have one teaspoon full of sugar per cup of coffee in the moring, mostly two cups sometimes three, outside of that no added sugar. The only differece in my diet was cutting off all calories after 4 PM. Also my energy better. I think it has something to do with insulin resistance. Not that I was diagnosed but if I did cheat and eat something sweat I noticed I started feeling strange afterward. Eyes would go out focus, and energy would be low.

  5. Yeah eating a ton of saturated fat and listening to Jimmy Moores advice on how to be healthy never did quite seem like a great idea.

  6. Only vegans have an average BMI that's considered healthy. I know BMI isn't the best indicator of health, but damn it definitely shows how easy it is to maintain a healthy weight on a plantbased diet. Keto is pure misinformation.

  7. Dr. Greger uses phony-studies, and fake-science. He is 100% WRONG about patients with atherosclerosis! Nuts are deadly for heart patients with clogged arteries. Look at all the reputable, accurate, honest studies published by Dr Esselstyn, and Dr Dean Ornish. Shame on Dr. Greger(who has never treated a patient in his life). He just repeats the false claims from the nut industry. He is actually killing patients with atherosclerosis. I used to be a huge supporter of Dr. Greger. Not anymore.He is dangerous.

  8. If you are not fat adapted, then you can’t expect to lose fat on a ketogenic diet. It takes weeks to months to get fat adapted. In this study, they started out by getting the patients to be insulin resistant and then switching to low carb diet thus setting them up for failure in the short term.
    The ketogenic diet does not work on a short term basis if you are not fat adapted. Eventually you would begin consuming less fat because you would be burning more of your own fat.

  9. 4:17 And that's why we have the carnivore diet. Nice bias, Mr Greger. Wish it held up under scrutiny and not just in the hands of an anti-meat clown.

  10. The smarmy delivery makes me question both the information and motivations behind it. Read the WIRED article. Clicked on a link provided in the WIRED article Read that. Noticed side bar links to pubmed and looked over those. Clicked on one Diet study linking obesity possibly to fetal exposure to High Fructose Corn Syrup during pregnancy. I am suspicious of the funding behind this site. Thumbs down.

  11. Keto has the good result, and It should not be the cause of muscle loss. Others may not do it the right way that is why there's negative results.

  12. It is already known in low-carb practice that water weight is lost in the first 1 to 2 weeks, BUT, after that, fat loss takes place. It is already known that excessive dietary fat can stall weight loss, BUT, knowledgeable scientists and doctors will tell you to increase protein instead of fat when this occurs. It is already known that muscle mass loss occurs during initial fat adaptation, BUT after that occurs, great strength gains can be made.

    Good job focusing on one study from years ago. The reason people do keto is that they see it work in others.

  13. What type of fat was used in the study? What type of carbs? This is the problem with a lot nutrition science. It's oversimplifies food into it's macros, without taking QUALITY into account. High fructose corn syrup is not the same as a sweet potato, and Canola oil or corn oil is not the same as an avocado or grass-finished beef fat. If you conduct a study and give people shitty fat to eat, then yeah, you're probably going to get shitty results. It's so insane. The truth is, you can eat an unhealthy vegan diet, and you can eat an unhealthy Keto diet. Conversely, there are people out there thriving on a vegan diet, and people thriving on a Keto diet, and even a carnivore diet…. Ever wonder that is? Maybe because the importance of QUALITY of food, along with other healthy lifestyle factors (exercise, sleep quality, sunlight, stress levels) supersedes the oversimplification of AMOUNT OF MACROS (protein, fat, carbs)…

  14. Such BS, I went from being a type 2 diabetic and a BMI of 44. My a1c was a 14+. In 3 months it went to a 5.4 and in 14 months I lost 55 lb and my BMI is 21. Keto 💪 baby. Just like a veganism, you can healthy and you can eat crap.

  15. I switched to a keto/carnivore diet 6 months ago. I've had incredible results. I was in good shape before but now my body fat is around 10% while I also managed to add muscle mass. I feel strong and healthy like I'm 25 again (I'm 43). Everything is better now – skin, hair, endurance, strength, sex drive. Everyone I know who actually tried the keto diet has similar success stories. I'm sick of people trying to discredit the keto diet without having actually tried it themselves. I tried a vegan diet for a month once. I felt weak the whole time.

Leave a Reply

Your email address will not be published.