9 Ketogenic Diet Myths

Let me burst your bubble right here at the beginning. This list is for people who are already following a ketogenic diet or are considering beginning one specifically for the purpose of losing body fat. If you’re looking for a nice, solid debunking of other myths about this way of eating (e.g., “All that saturated fat will clog your arteries,” “All that protein is bad for the kidneys,” “You need carbs for energy,” “I learned in medical school four hundred years ago that ketosis is fatal,” and other such nonsense), here are two excellent debunkings: one from Authority Nutrition, and one from my dear friend Ellen Davis, creator of Ketogenic Diet Resource, which is the single best one-stop-shop, gateway entry I'm aware of for all things ketogenic-diet related. (And I'm not just saying that because Ellen's a friend. I'm saying it because it's true. The reason we became friends is because I came across her site a few years ago, and ... well, the rest is history.)

Why do these ideas need to be called out for the myths that they are?

Well, now that I’m participating more in social media related to low-carb and keto, I’m noticing—and I could be wrong, but I don’t think this is only my imagination—that there are a few falsehoods that have become quite pervasive in our community. So pervasive, in fact, that they persist despite being flat-out incorrect. And because they persist, we continue to see post after post after post on Facebook, Instagram, Twitter, and wherever else, from people at their wit's end because they aren’t losing fat, are gaining fat, or have not had every single longstanding malady resolve immediately upon ditching bread and loading up a cup of coffee with butter and coconut oil, or drowning everything in cheese, as others may have promised them would happen.  

If these individuals are lucky, they stumble upon a group where logic, sanity, science, long-term experience, and the attainment of actual results rule (rather than chasing ketones for the sake of high ketones). If they’re not lucky, they fall head-first into groups where the same-old not-helpful advice is parroted ad nauseum.

With this in mind, here is my own personal list of the top 9 biggest falsehoods regarding ketogenic diets for fat loss, along with "alternate versions," intended to help us see things from a different perspective. There are probably many more out there; these are just the ones that came to me first. If you have some favorites that I've missed here, share them in the comments so we can all collectively cringe! 

1.  I can eat unlimited fat and lose body fat.

2.  It’s not possible to gain body fat while in ketosis.

(Alternate version of numbers 1 and 2: insulin is the only thing that matters when it comes to the gain or loss of body fat, so as long as insulin levels are low, I will not and can not gain fat, regardless of anything and everything else going on in my life and my body.)

3.  I must be in ketosis in order to lose body fat. It is the only way.

(Alternate version of number 3: every single person on the planet who has ever lost body fat has done so via a ketogenic diet.)

4.  There is a direct relationship between ketone levels and fat loss: the higher my ketones, the more fat I will lose, and the more quickly I will lose it. Higher ketones mean more fat loss, because higher ketones cause greater fat loss. Fat loss is the result of high ketones.

(I don’t have an alternate version of this to illustrate how wrong it is. Frankly, it doesn’t need one. It’s just wrong. *Think, think, think…*  I guess I can give the example of an uncontrolled type 1 diabetic: they’re not losing fat because their ketones are [pathologically] high; their ketones are [pathologically] high because they’re hemorrhaging fatty acids out of their adipose tissue. High ketones are the result, not the cause, of breaking down large amounts of fat.)

5.  I must eat at least 70% of my calories from fat, or I’m not eating at “ketogenic ratios.”

6.  Going by macronutrient ratios (percentages of total calories from fat, protein, and carbohydrates, rather than absolute grams) is the best way to formulate a ketogenic diet for fat loss.

(Alternate version of numbers 5 and 6: ketogenic diets are defined by the macronutrient ratios. In other words, a diet consisting of 10,000 calories with 80% of total energy coming from fat, 12% from protein and just a teeny, tiny 8% from carbohydrate will be ketogenic simply because fat is 80% and carbs are a paltry 8%, even though 8% of 10,000 calories is 800 calories, or 200 grams of carbohydrate. Anyone out there think you can achieve nutritional ketosis eating 200 grams of carbohydrate? [Assuming you are not mainlining MCT oil and are not a T1 diabetic.]  There: “ratio” myth officially debunked. And no, I don't think anyone trying to lose body fat -- or for pretty much any other reason [except perhaps being an Olympic-caliber swimmer] is eating 10,000 calories a day. I'm just trying to illustrate the point is all.)

7.  If my blood ketone level is not above 1.0 mmol/L, I am not in ketosis, it is “not high enough,” or I am “doing it wrong.”

(Alternate version: Jeff Volek, PhD, RD, and Stephen Phinney, MD, PhD, are wrong when they say nutritional ketosis begins at blood β-OHB levels around 0.5 mmol/L. Dr. Phinney, who has been doing low carb research almost as long as Amy Berger has been alive, doesn’t know what he’s talking about, so you should listen to the “bros” in your Facebook group instead. Also: looking back at the debunking of number 4: WHO CARES WHAT YOUR KETONE LEVELS ARE?!  Since higher ketones do not cause greater fat loss, stop chasing ketones. Let me say that again: Since higher ketones do not cause greater fat loss, stop chasing ketones. For the specific goal of fat loss, it is more important to be fat-adapted and generally using fat for fuel than to be “in ketosis” at all times. Does this mean it’s never a good idea to aim for high ketones and take specific measures to produce them [e.g. fasting, exogenous ketones, MCT oil]? No, of course not. There are #contexts in which it very well could be appropriate to deliberately modulate specific factors in order to generate higher ketones. What contexts? Maybe cancer treatment, traumatic brain injury, Alzheimer’s disease, or other neurological issues. My point is, these #contexts are NOT FAT LOSS.)

8.  Carrots, red/orange/yellow bell peppers, beets, and other “sweet-ish” vegetables are outright prohibited on a ketogenic diet.

(Alternate version of number 8: it is not physiologically possible to consume one carrot, or half a red pepper and remain in ketosis. If I want to lose fat on a ketogenic diet, I can never, ever have a salad with shredded carrots or julienned pepper. If someone tries to serve me carrots at Christmas dinner, I will disown them because they don’t understand my diet, they are trying to poison me with their carby garbage, and I will never, ever attend another holiday at their house again, because if they’re gonna serve carrots, they might as well just tie me up and force-feed me white bread slathered with grape jam.) I’m not the biggest fan of the Whole30® program, but I agree with the creators when they called this “the carrot train to crazytown.” (More on this in the upcoming mega-epic keto rant I warned you about last time.)

9.  A ketogenic diet is pure magic, and it will fix all aspects of my life and my health. If I hate my job, keto will make me happy. If I no longer love (or even like) my spouse or significant other, keto will magically repair my relationship. If I'm drowning under heaps of financial debt, keto will help me win the lottery. People don’t like me because I’m an *sshole; keto will turn me into a kind, compassionate person.^* Keto is good for everything in life – Every. Single. Thing. – and if my life is not perfect after “going keto,” then I’m doing it wrong.

*I actually think this is not all that far-fetched, IF someone’s *sshole-ness stems from anger and irritability resulting mostly from hypoglycemia. In cases where mood swings and general un-likability stem from wacky hormones and the brain going crazy on sugar (or lack thereof), then I can totally see keto making someone less of a d*ck. (Keto does have mood stabilizing effects, and it’s even been known to help bipolar!)

(Alternate version of number 9: any diet, whether ketogenic or not, is the secret to happiness. For a good debunking, see this post on Vitamin J. [Warning: it’s one of my longest ever, so save it for some night when you have trouble sleeping.])

I realize that my alternate versions of these ideas are a bit extreme. Normally I actually kinda hate when people make arguments using extreme examples that typically don’t occur in the real world, but I think this approach can be helpful sometimes—like now. I only used the extremes to point out how laughable—and misguided—some of this stuff is. We tend to be blinded by our own biases and beliefs, and when this stuff starts stinking of religious zealotry and closed-mindedness, well, I refuse to participate. I don’t think low-carb and ketogenic diets are the only way people can lose weight and be healthy. And I think sometimes we do get a little too enamored with our own principles. And sometimes we just need a little reality check.

For another good reality check regarding some potential falsehoods we allow ourselves to believe about low-carb and keto diets, here’s another post from Authority Nutrition. (What can I say? Kris Gunnars and the people who write for him do great work.)

More rants coming soon!  ;-)

Disclaimer: Amy Berger, MS, CNS, NTP, is not a physician and Tuit Nutrition, LLC, is not a medical practice. The information contained on this site is not intended to diagnose, treat, cure, or prevent any medical condition and is not to be used as a substitute for the care and guidance of a physician. Links in this post and all others may direct you to amazon.com, where I will receive a small amount of the purchase price of any items you buy through my affiliate links.