Keto Diet Theory Put to the Test

Do low carb and ketogenic diets have a metabolic advantage for weight loss?

Stay tuned for:

The more things change, the more they stay the same. I did a whole website about the Atkin’s Diet and sadly people keep falling into the low carb trap.

Some of my older videos on low-carb diets include:

Thanks for watching. I hope you’ll join in the evidence-based nutrition revolution!
-Michael Greger, MD FACLM

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Image credit: Ted Eytan / flickr

[fromwhativeread]

My mom started the keto diet over a year ago to lose weight and help control her type 2 diabetes. She succeeded in those two objectives, but suffered a stroke last month. I have not heard anyone mention her stroke as being diet related, but everything I’ve ever heard about nutrition makes me believe it was. More and more friends of mine are going keto. I hate to be the sanctimonious vegan, but I genuinely worry for their health.

[maxstarn]

When he says “PUT IT TO THE TEST” and “UNTIL...NOW” I get excited

[siphoningblues]

Well at least they had the decency to accurately report their findings instead of cooking numbers to suit their agenda.

[Kathy_Is_Blessed]

Thank you Doctor. I am so very thankful I found your website and heard about a plant-based lifestyle after my heart attack 4 years ago, at age 61.
I’ve never felt better. ♥️

[zorro]

It's time for them to rename this diet again.

[MrKobayashi]

Ok, so I was sceptical about this video and just to see if I could 'trust' it I headed quickly over to the sources. Half of them were from 2002 (interesting) and I clicked on a more recent one, the one where Dr. Greger mentions that keto crossfiters lost muscle mass. Just reading this abstract you can already tell Dr. Greger just picks out what he wants from these studies, isolates it and uses it for his point.

The end of the abstract states: 'While our n-sizes were limited [my add: control group n=5, keto dieters n=7 btw], these preliminary data suggest that adopting a ketogenic diet causes marked reductions in whole-body adiposity while not impacting performance measures in recreationally-trained CrossFit trainees. Whether decrements in dual-leg muscle mass and vastus lateralis thickness in KD participants were due to fluid shifts remain unresolved, and increased LDL-C in these individuals warrants further investigation.'

So to summarize: Keto dieters lost weight, didn't have lower performance, no data on if actually lean body mass was lost or just fluid shifts, and some controversial blood markers shifted to warrant further investigation.
But all Dr. Greger takes from this is "keto dieters are losing lean body mass from this diet".

Tell me this is not wilfully deceiving by Dr. Greger. So much for your 'NutritionFacts'.

I assume the rest of his points are equally cherry picked, isolated and overstated. If you want to be taken seriously you should never be caught obviously deceiving like this. And this was literally the first thing I picked out to look further into and right away found this discrepancy. Honest mistakes are one thing, but it is obvious this guy presents all this stuff only to fit what he wants to be true. I'll stick to thinking for myself.

[johnsnow]

I was a healthy man of 45 years, and was stupid enough to do a keto diet, for 2 years. The outcome was: gained weight, high cholesterol, very bad mood, muscle cramps and finally heart arrythmia which led to a stroke. Now, since 2 years I am more or less on Dr Gregers way of eating, and all shitty keto symptoms gone. I would really like to sue them keto charlatans one day!

[impressions]

Of course carbs are fatning, I realized 30 years ago while travelling around East Asia that rice and veg eating people were morbidly fat and Americans so trim that you could walk all day amongst thousands and thousands of people and not see one single fat person. Total common sense.

[jakobdavenport]

I’m no expert, but I know it is misleading to point out the loss in muscle mass. From my understanding, this loss is a temporary reduction in glycogen stores and water mass in the muscles. It’s not a loss of actual muscle fibers.

[RedPillVegan]

Jason Fung tho. The study was biased by vegans tho. Twitter tho. The people's ketones were biased by Vegetable intake (known carcinogen) tho. They were not fasted 18/6 tho. They were still addicted to carbs tho. Soy.

[TechnicFlow]

So why does it work?

I'm not saying you're wrong or that your research isn't on point but literally everyone I know who has tried the ketogenic diet has lost significant weight, become healthier (I can only verify myself in this claim) and kept the weight off? I went from 240 to 145lb and ended up becoming a semi pro (cat 3) crit racer all while on vegetarian keto, I almost never get sick and my blood panels I get done regularly for cycling are as perfect as they can be.

My roommate went from 360 and is now at 240.

My coworker went from 250 to 180 now.

My cousin has lost 30lbs in 3 months.

Then there's literally thousands of people on Reddit or other social media reporting the same success. How am I supposed to look at all that clear evidence that takes 0 research to see and buy into this video? The other thing is that you're getting the reason for keto wrong. Yes people talk about more fat burning but that's not the point. The point is appetite suppression and increased energy. You also don't shovel down fat because you're not eating carbs, because of the suppression of appetite you don't eat as much until you get down to a low BMI like me where I do need to increase my fat intake to maintain weight. But on the weight loss journey I was easily able to just slip right into intermittent fasting.

Then there's piles of research that say the opposite of what your and your research claim. So in a topic even researchers can't agree on I'll go with what I've seen.

[ryantfinchum]

As a result of reading this study, the rate of cognitive dissonance among ketogenic diet proponents went up 100%

[Prickly_G]

Thank you Dr. Gregor for setting me straight! I have been doing keto for 3 months, and the scale told me I have lost about 30 pounds. But now that I have watched your video, with all of your helpful stats, facts, and words, I realize the scale has lied to me! Keep up the great work. :/

[Chris-MusicTheoryAndFretboard]

Excellent video. Kevin Bass is also doing a thorough debunk of low-carb claims on his website at "Nutritional Revolution". The only reason people lose weight on Keto is because they cut calories. It's really that simple. And.. it doesn't work for many people too. I wish they weren't so zealous about it. Lots of former low-carbers have moved on to more reasonable approaches to weight loss that works for them.

[wahidurrahmansaadi]

Dr. Greger, I am sure you are a FBI agent undercover as a nutritionist 😝
Ketogenic Diet BUSTED 😂

[nickmeale]

Finding 'your own' sweet spot of daily carbs is the key to your own weightloss. As the same with fats. Your body talks to you. You need only listen.

[willtaylor]

I did Keto diet about 10 years ago (about 1 year before I went vegan). Holy crap I felt like trash. I stuck with it for about 1 year and felt absolutley dreadful the entire time. It detroyed my cycling ability (I went from being able to smash out 70kms per day to struggling to ride 9kms to work). My sweat smelled like vinegar. I had all sorts of GI issues including (but not limited to) severe constipation and crippling gut pain (that caused me to leave work and go home about 7 times). I could go on. It was bloody aweful. Then I went vegan and started smashing the fruit, veges, lentils/beans, rice and potatoes/sweet potatoes and ... everything started working again. I could also actually think clearly again. For me Keto was an unmitigated disaster. WPF for the win! Just as an aside has there been any research done on doing a WPF Keto diet? That would be interesting. I think it'd be MUCH better than animal based.

[litehold]

This horrible garbage killed my mom. She was influenced to try keto by that article, and died of a massive heart attack. She had been eating plant-based some years prior and was doing well, then all of the "butter is good" misleading information was all over the place, so she decided to try "keto".

[megavegan]

For all the Keto PhDs in the comments arguing that the study participants weren't given enough time to get into ketosis, you should know that they tested for respiratory quotient; all the participants were 'fat-adapted' after the 1st week of switching to the keto phase of the study.

[jjshuffe]

I was on the keto diet for 10 months we went on vacation and I went off of the diet for the past 2 months What I learned while I was on the keto diet is my health improved quickly to the point where I had to lower my meds in the first 2 month blood pressure medications and diabetic meds I lost 55lbs in the first 3months which was great but at the same time freaked me out so I maintained that weight for the next 3 months then I lost anothe 20lbs over the last 4 months also while on the keto diet my choleterol levels got normal and my triglycerides dropped from 290 down to 160 when I went on vacation in July and started to eat a high carb diet all my cholesterol levels went back to where they were the previous year before I started the keto diet plus my a1c levels went up from 4.3 to 5.0 A1C levels are a measure of sugar in the blood 5.0 is still a good number but my cholesterol and triglycerides went back to the unhealthy levels. So needless to say at the beginning of September I went back on the keto diet. I am doing the keto diet for health reasons as well as losing weight and I don't buy any of their products except nutrition yeast which I happen to like on my daily salad. You guys can bash this diet any way you like I tried all the other diets the diabetic diet the heart association diet the diets the doctors told to follow and none of these worked but I got healthy on the keto diet and that's all that matters to me.