Damaging Myths About Dietary Carbohydrates: Part 1

*Part 2 is up. Read it here.

With my previous two posts honing in on a popular, yet badly misinformed dietition’s ridiculous claims surrounding the relevance of calories in fat loss and overall metabolic health, I wanted to begin a new series on an oft demonized macronutrient; the delicious carbohydrate.

If you’ve fallen for the nonsense spread about by Gary Taubes and his devout followers, you probably believe that carbohydrates are at the root of all fat gain, for reasons I will get to in a moment.

Now, not only is this completely wrong, it’s misleading and disingenuous. And by now, you know I don’t take kindly to misleading blanket statements, and neither should anyone else.

The belief that carbohydrates drive obesity is not just silly and overly simplistic; it’s completely incorrect from a scientific standpoint.

I know that popular gurus don’t take kindly to the presentation of actual facts, as they tend to prefer their comfy estate on fantasy island, but hopefully you’re someone who actually cares about the objective scientific evidence.

You don’t have magical insulin fairies floating around your cells, waiting to store those wretched carbohydrates, longing to make you obese and diabetic.

This is the insulin fairy, the true cause of our obesity epidemic.

Let’s relieve carbohydrates from some of the dogma and extremism.

Myth #1: Low Carbohydrate Diets Lead to Fat Loss, Therefore They Are the Cause of Fat Gain

This myth doesn’t come from the ‘experts’ as much as it comes from the dedicated followers of the low carb philosophy. If removing something from the diet fixes the problem, however temporarily, then what was cut out must have caused the problem in the first place. I see this all the time regarding gluten, sugar, soda, etc. So, if cutting carbs/eating carbs isn’t the sole cause of fat loss/fat gain, what is? Let’s take a look.

The standard American diet is anywhere from 40-60% carbohydrate, give or take a few percent in either direction. Now, what do you think happens when you cut from 60% carbohydrates to 20% carbohydrates? Unless the carbohydrates are replaced with fat isocalorically (this does happen, but not very often it seems), you will be cutting a huge chunk of your overall calorie intake.

Let’s look at this in the context of a 2000 calorie diet. If this diet is composed of 60% carbohydrates, that’s 300 grams, which totals 1200 calories. We can all agree that 1200 is a large portion of 2000, I hope.

So, if one were to decrease their carbohydrate intake to 20% of total calories, that would be 400 calories coming from carbs, as opposed to 1200 (a drastic difference of 800 calories). With the addition of more dietary fat (which slows gastric emptying, leaving you fuller, longer) and spontaneously increased protein intake (usually due to more meat consumption), there is bound to be an unconscious reduction in overall food intake due to increased satiety.

There’s no magic to low carbohydrate diets in comparison to high carb diets (3, 4, 5 , 6, 7, 8, 9). Calories are king.

Now let’s expand on that a bit with the next myth…

Myth #2: Carbohydrates are Fattening in Comparison to Dietary Fat

The title of this section reads like it was taken straight from a comic strip. Anyone with a grasp on basic physiology and nutritional science would call bullshit; and they would be 100% justified in doing so.

Now that we’ve discovered that dietary fat doesn’t have a direct causal relationship with cardiovascular disease, people seem to think it is somehow more nutritious and less fattening than carbohydrates. People are so excited that saturated fat isn’t going to kill them that they decide to toss 800 calories worth of it into their morning coffee. It’s funny how the paradigm shifts, ain’t it?

The great thing about reality is that it doesn’t care what you think. Facts are facts, reality is reality, and your opinions don’t change anything.

Let’s look at the reality: dietary fat is the macronutrient that is stored with the most efficiency

When you consume dietary fat, fat oxidation increases very little in response. However, when you consume carbohydrates, carbohydrate oxidation increases dramatically, alongside an increase glycogen storage (1). Contrary to what now seems to be a common belief, it’s very difficult for humans to convert dietary carbohydrates to fat (de novo lipogenesis).

Now, this does not mean that you should not eat any dietary fat. It doesn’t even mean that you shouldn’t eat a high fat diet. It does, however, mean that energy balance, once again, reigns supreme. If you create a caloric surplus with only dietary fat, you will gain body fat much more efficiently than if the surplus were to come from pure carbohydrate.

To add on to the carbohydrates equal insulin which equals fat gain point: supporters of the carbohydrate/insulin hypothesis of obesity have a tendency to extrapolate transient effects to the long term. For example, we know that insulin inhibits lipolysis (fat burning) in the short term. But that does not mean insulin makes you fat over the long term.

Insulin inhibits lipolysis because glucose is readily available to be used for fuel. Why would the body release fat from fat cells when glucose is available to be utilized? Energy balance over the entire day is much more important than postprandial  insulin levels in terms of fat loss. The body is constantly shifting between burning glucose and fat.

Insulin is often referred to as the “fat storage hormone”. However, it’s more honest and all-encompassing to use Stephan Guyenet’s definition (from this post):

“Its main role is to manage circulating concentrations of nutrients (principally glucose and fatty acids, the body’s two main fuels), keeping them within a fairly narrow range.”

If insulin was not there to do it’s job, there would be a constant circulation of fatty acids and glucose in the blood, which is seen in obesity and insulin resistance. Not good.

Anthony Colpo, in his most recent article (read it here) discussing the silliness of the insulin hypothesis of obesity, writes:

“The reason it’s rubbish […] is because it ignores critical events that promptly follow on from the immediate changes in lipolysis and lipogenesis. Namely, when you eat more carbs, rather than converting the extra carbohydrate to fat and stockpiling it in adipose cells, the body responds to increases in carbohydrate intake simply by increasing the amount of carbohydrate used as fuel. At the same time, the body decreases the amount of fat used for energy[7]. That’s why, when volunteers are fed high- and low-carbohydrate diets of equal caloric content, the subsequent differences in lipogenesis are so small as to be meaningless in terms of fat gain[7,8].”

Enough said.

Side Note: Carbohydrates are Extremely Beneficial for Muscle Gain, Fat is Not

Carbohydrates are “anabolic” and they fuel exercise performance, whereas fat is not and does not. Sufficient carbohydrate intake while in a caloric surplus will ensure that glycogen stores remain full and you’re able to blast through whatever activity you take part in.

On the flip side, if you’re in a caloric deficit or eating at maintenance, macronutrient composition is pretty much irrelevant (aside from protein intake, which should remain relatively high to ensure maximal lean mass retention). Optimal diet composition is going to come down to personal preference and what makes you feel best. Some enjoy eating low carb because it can be more filling, and some will want to eat as many carbs as possible. The latter is especially true for athletes and those who are highly active on a consistent basis.

So, if you’re in a caloric deficit you will not put on body fat, regardless of the macronutrient composition of the diet. People spouting the ‘carbs make you fat’ dogma need to wake up and smell the basic facts.

If your goal is to lose body fat: establish calorie intake, establish protein intake, and adjust the rest based upon your personal preferences. Demonizing one macronutrient or the other is futile as it takes focus away from the overall picture and the most important factor in body fat loss; a caloric deficit.

Anthony Colpo, to quote him once more,  says it best in his post titled “Carbohydrates are Good; Dogma is Evil!“:

“People can wank on and on about how much they hate the concept of calories in versus calories out, but petulant ranting against reality doesn’t change the indisputable fact that without a calorie deficit, no fat-derived weight loss will occur.”

Beautiful. Some seem to have this fantasy that if they hate calories enough, eventually they will become irrelevant. Sorry to dissappoint you, but you can hate calories all you want; they’re not going anywhere, and they must be accounted for.

If you’re interested in reading more about the oft touted carbohydrate hypothesis of obesity, you can check out  Stephan Guyenet’s merciless obliteration of it here.

Long story short, carbohydrates are not inherently fattening, and they’re not going to turn you into an insulin resistant mess. It’s time to start disregarding the ‘experts’ who make a living cherry-picking data that supports their cherished viewpoint while ignoring data that proves their ridiculous ideas invalid.

Myth #3: Carbohydrates are Not “Essential”, Therefore They are Unimportant

The zealous low carbers love this one. Your body can make it’s own glucose, therefore technically, no one needs to eat carbohydrates.

Yes, this is true. But there are several crucial problems with this argument that need to be addressed.

First of all, yes, the body can makes its own glucose via gluconeogenesis. But why would anyone want this? Why would anyone want amino acids or odd-chained fatty acids to be their main source of glucose?

Personally, I would much rather the delicious protein I consume go towards supporting structure rather than providing me with glucose that I could easily get from whole sources (mmmm, potatoes).

Amino acid catabolism. Uhhhh, no thanks.

And I think most who are active and care about their body composition will share the same view. Gluconeogenesis is certainly not the most efficient process, considering you could just consume dietary carbohydrates and be dandy (and you’ll probably feel better, too).

Another huge issue with this argument is the assumption that “essential” is somehow analogous to “unimportant”. I don’t want to attack a strawman here, so I will note that not everyone believes this to be true, but there are certainly some who do (as I mentioned above, it’s usually the overly dogmatic low carb advocates).

Look, there’s a massive difference between surviving and thriving. Sure you can survive without consuming any dietary carbohydrates and deriving your glucose needs from amino acids among other sources, but again, you’re distracting amino acids from their primary endeavor; supporting and building structure.

Also, there are plenty of “nonessential” amino acids (such as taurine, alanine, and glutamine) and fatty acids (such as palmeric acid, stearic acid, and lauric acid) , but you would be a fool to exclude them from your diet because off the fact that they aren’t “essential”.

Carbohydrates such as fruits and vegetables are obviously excellent sources of nutrients and fiber. I’m pretty sure no one recommends avoiding vegetables, but because of the recent fructose craze, people have begun to demonize fruit. This is completely silly. I love fruit, I eat a ton of it daily, and I haven’t died from fatty liver disease or developed insulin resistance. Live a little…

So, nonessential does not mean unimportant.

Having friends isn’t essential, and neither is going on vacation, but I don’t see anyone cutting those two things out of their lives. Carbohydrates serve an excellent purpose in the diet, especially for those who are highly active. While there are some athletes who do well on a ketogenic diet, they are a far-cry from the majority.

If you’ve been cutting carbs out of your diet, seriously ask yourself: why? If you’ve fallen into the trap of believing they make you fat, hopefully I’ve done a good enough job convincing you that they don’t above.

One More Thing…

Let me touch on one more point before I wrap this thing up: when I refer to carbs, most people hear donuts, twinkies, and cupcakes. Folks, those are as much fat as they are carbs. So when discussing carbs, it’s important to actually discuss carbs, and not refined sugars slathered in artificial trans fats.

While processed foods can certainly have their place in the diet, I’m of the opinion that at least 80% of the overall diet should be comprised of whole foods. If you want to go 100%, great. But, for those who like a bit of flexibility, the 80/20 rule seems to work well.

So that means that most of your carbohydrate intake should come from fruits, potatoes, veggies, rice, and other grains if you tolerate them.

The above carbohydrate sources are not the problem, although Taubes seems to believe the potato is evil.

I guess you can only eat potatoes if you’re a twenty five year old marathon runner. And people still take him seriously?

Wrap Up

You should come away from at least one point from this post: carbohydrates are no more the cause of the obesity epidemic than dietary fat. The low-fat craze has come and gone, and it’s time for the low-carb craze to get to steppin’ as well. I said this earlier, but I’ll say it once more: demonizing one macronutrient is completely useless.

Fat gain is not caused by carbs, insulin, dietary fat, sugar, or processed foods; it’s all of these things combined. A chronic surplus of calories combined with a sedentary lifestyle is a recipe for obesity (2), yet people still believe “it’s the carbs, bro”. Sorry, time to pick on something else. Maybe they’ll go after protein next, who knows?

If you enjoyed this post, be sure to look out for Part 2 coming out either tomorrow or Wednesday. If you’re subscribed to my email newsletter, you’ll be notified when it is published. If you’re not subscribed, WTF? Sign up, now. I mean it.

Have an awesome day.

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  1. says

    I found this line in your post very telling: “Most of your carbohydrate intake should come from fruits, potatoes, veggies, rice, and other grains if you tolerate them.”

    The problem is, Jake, most of us CAN’T tolerate those foods because the metabolic damage has been done from our past nutritional choices. If you can consume all of those things without consequences to your weight and health, then I’m the first to shake your hand, congratulate you and wish you well on your high-carb diet. But those do nothing but spike my blood sugar and insulin levels, pack on the pounds, and make my health decidedly worse, not better. Dietary dogma never gets anyone anywhere except down the road to frustration and failure.

    • Jake Johnson says

      Hey Jimmy,

      Thanks for commenting. I do realize that there are some who cannot tolerate certain foods due to metabolic issues. However, too often people blame the foods (such as the ones listed in the quote from my post) rather than their faulty metabolism. The harsh reality is that you cannot blame the potato for causing hyperinsulinemia and plummeting blood glucose, you must blame your metabolism’s inability to effectively oxidize glucose. Blaming the food means ignoring the underlying problem (not saying you’re doing this, but it’s quite common).

      And you’re right, dietary dogma doesn’t help anyone. If there’s something dogmatic about this post, feel free to point it out to me. I think this line is very telling as well: “Optimal diet composition is going to come down to personal preference and what makes you feel best.”

      And this one: “If your goal is to lose body fat: establish calorie intake, establish protein intake, and adjust the rest based upon your personal preferences.”

      All nutritional advice should be fit to the individual, and I have never said otherwise. This post was meant to address common myths revolving carbohydrates, not to tell everyone to eat carbohydrates.

      Hope this helps.


      • says

        Those comments on diet dogma were more generalized in the overall debate of ideas, not necessarily at you. Interesting article which is why I shared it on social media. We’ll discuss soon on my Friday podcast.

        • Jake Johnson says

          Alright cool, I greatly appreciate the shares. Like I mentioned to the person who responded to your share on Twitter, I’m always open for feedback and criticism regarding the validity of the points I’ve brought up in the post. Part 2 will be up soon as well.


          • Bob Carson says

            “The harsh reality is that you cannot blame the potato for causing hyperinsulinemia and plummeting blood glucose, you must blame your metabolism’s inability to effectively oxidize glucose.”

            Jimmy is not wanting to entertain that this might be correct. Nothing against him, but I strongly disagree with his obvious bias. I mean, the man has a brand to prop up and justify.

            Now having said that, I don’t want to sound like an arse. I stay out of the online diet “battles” because I want everyone to do well and generally comments like the one that I just make is not conducive to helping anyone. Sometimes I simply feel the need to point out obvious bias.

          • says

            No “obvious bias” from me, Bob. Anyone who follows my work knows my philosophy has always been to find what works for you. That’s it. No one size fits all approach. It’s why I appreciated Jake’s post.

    • says

      Jimmy, EVERY test you ever posted on your blood sugar has demonstrated that you are profoundly normal in that department, though bound and determined to destroy that. With each increasingly extreme diet measure you have taken, your FBG has gone more whacky to where now you need berberine. This is reversible with just a little moderation in the true dietary culprit.

  2. says

    Nice post … I would change one line “If removing something from the diet fixes the problem, then what was cut out must have caused the problem in the first place.” should read “If removing something from the diet fixes the problem, HOWEVER TEMPORARILY, then what was cut out must have caused the problem in the first place.”

  3. Lisa says

    Jake, I would have to disagree with your assertion that there’s no dietary dogma in your post. “Calories are king” is dietary dogma, and one which I believe is as overly simplistic as you accuse the insulin hypothesis of being. In 10 years of reading pretty much every dietary philosophy out there, I don’t think anyone’s really nailed the precise mechanisms behind fat gain/loss, and I certainly don’t believe the body works the way a bomb calorimeter does. I and many others (see Sam Feltham’s recent experiment – whether or not you subscribe to his dietary philosophy) have found that we are able to maintain body weight at a higher number of calories when restricting carbohydrates than we can when we’re not restricting them (and this is after more than a decade of careful tracking of weight, food intake and energy expenditure). This doesn’t mean I never eat carbohydrates, but it does mean I have to lower my total caloric intake when I do if I don’t want to gain weight. If everything boiled down to a simple calories in/calories out equation, this shouldn’t be the case. And the idea that all people who go on low-carb diets are simply losing weight because they’re not replacing the carbs in their diet with other macronutrients and therefore taking in fewer calories is also a gross oversimplification. Again, this might be the case for some, but for myself and many others I know who’ve tried low-carb eating, the exact opposite is true – more calories can be consumed without gaining weight than was possible on a high-carb diet. The fact that this is not true for everyone, and that the mechanism behind it may not yet be fully known, doesn’t mean it doesn’t work for many people who’ve tried it. Does this have to do with previous metabolic damage? Perhaps. Just like people with compromised kidneys may not be able to consume the same amount of protein that healthy people can – perhaps people with compromised metabolisms from years of junk food abuse may not be able to properly process carbohydrates. But if restricting carbohydrates turns out to be the answer for those people, what’s wrong with that? Just because insulin may not be the answer to the puzzle, doesn’t mean calories in/calories out is the whole story either.

    • Jake Johnson says

      Hey Lisa,

      Thanks for commenting. Based upon the current controlled research (not wacky experiments) that we have available, calories seem to be king. When protein and calories are controlled, there seems to be no difference in weight loss between high carb and low carb. If you have research that shows something to the contrary, feel free to post it here. I will agree with you that counting calories is not the end-all-be-all as we cannot practically measure the exact amount of calories that we actually absorb; add in the thermic effect of food and variations in energy expenditure day to day, and there is quite a bit that we cannot measure in a practical setting. However, at this point, calories are the best measurement tool we’ve got, and they seem to give a pretty accurate estimate.

      The controlled research consistently shows that a caloric deficit leads to weight loss. I’m not discounting your experience with different macro compositions, however, it’s difficult to make assertions based upon anecdotal evidence. Again, if you have controlled evidence that shows someone gaining weight in a caloric deficit when carbs are introduced, feel free to share.

      I never said there’s anything wrong with restricting carbohydrates if that works for you.

      That said, I’m absolutely convinced that excess calorie consumption (on top of decreased activity levels) is the cause of overweight and obesity. But we just have to figure out why we’re eating too much. I’m always open to learning, so if you can show evidence to the contrary, please do.



  4. says

    Great article as usual Jake, you are right on my man. @Lisa As for calories being dogma – hey it may not be 100% as simple as calories in vs. calories out but it’s pretty close, and it’s by FAR the best measurement system available. Calories are indeed King.

    Going to read part II tomorrow, it’s sleepy time.


    P.S. I hope the insulin fairy comes to visit me tonight, she’s kinda hot.

    • Jake Johnson says

      Thanks Jay.

      It’s funny how everyone makes the argument that calorie counting isn’t 100% accurate, therefore it’s ineffective. And then they’ll lose weight without counting calories and use that as an argument that calories don’t count. It’s poor logic, really. I love this article by Yoni Freedhoff (http://greatist.com/health/yoni-freedhoff-count-calories) as he explains some of the flaws behind calorie counting, and then he goes on to explain why people can still benefit greatly from it. Overall, it just comes down to personal preferences. Me personally: I would overeat consistently if I didn’t count calories. Some are the opposite. To each their own, as always.

      Hope you enjoy Part 2 (and your visit from Ms. Insulin)!



  1. […] Calorie counting seems to have taken a load of criticism over the past few years. With the growth of the nonsensical message that calories don’t matter, people have resorted to “intuitive” eating, or just counting carbohydrates because they feel that carbohydrate intake is the main arbiter of weight gain or weight loss (hint: it’s not). […]

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