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How Insulin Really Works: It Causes Fat Storage…But Doesn’t Make You Fat

How Insulin Really Works: It Causes Fat Storage…But Doesn’t Make You Fat

Many people believe that insulin is to blame for the obesity epidemic. When you understand how it actually works, you’ll know why this is a lie.


Insulin has been taking quite a beating these days.

If we’re to listen to some “experts,” it’s an evil hormone whose sole goal is making us fat, type 2 diabetics.

Furthermore, we’re told that carbohydrates also are in on the conspiracy. By eating carbs, we open the insulin floodgates and wreak havoc in our bodies.

How true are these claims, though? Does it really make sense that our bodies would come with an insidious mechanism to punish carbohydrate intake?













Let’s find out.

What is Insulin, Anyway?

Insulin is a hormone, which means it’s a substance the body produces to affect the functions of organs or tissues, and it’s made and released into the blood by the pancreas.

Insulin’s job is a very important one: when you eat food, it’s broken down into basic nutrients (protein breaks down into amino acids; dietary fats into fatty acids; and carbohydrates into glucose), which make their way into the bloodstream.

These nutrients must then be moved from the blood into muscle and fat cells for use or storage, and that’s where insulin comes into play: it helps shuttle the nutrients into cells by “telling” the cells to open up and absorb them.

So, whenever you eat food, your pancreas releases insulin into the blood. As the nutrients are slowly absorbed into cells, insulin levels drop, until finally all the nutrients are absorbed, and insulin levels then remain steady at a low, “baseline” level.

This cycle occurs every time you eat food: amino acids, fatty acids, and/or glucose find their way into your blood, and they’re joined by additional insulin, which ushers them into cells. Once the job is done, insulin levels drop to “normal” and the pancreas waits for us to eat food again and repeat the process.

What’s the Problem With Insulin, Then?

When explained like that, insulin sounds like an alright dude. We can’t live without it.

Why, then, is it viciously attacked by mainstream diet “gurus”? Why are we told it makes us fat and sick?

Because one of insulin’s vital roles in the body relates to fat storage: it inhibits the breakdown of fat cells and stimulates the creation of body fat. That is, insulin tells the body to stop burning its fat stores and instead, absorb some of the fatty acids and glucose in the blood and turn them into more body fat.

This makes it an easy target and scapegoat, and this is why the carbohydrate is often pilloried right next to it. The “logic” goes like this:

High-carb diet = high insulin levels = burn less fat and store more = get fatter and fatter

And then, as a corollary:

Low-carb diet = low insulin levels = burn more fat and store less = stay lean

At first glance, these statements sound plausible. Simple explanations are popular.

But they’re based on myths and pseudoscience.

Insulin Triggers Fat Storage…But It Doesn’t Make You Fat

One of the common charges against carbohydrates and insulin is that by eating a lot of carbs every day, your insulin levels will remain chronically high. This, in turn, (supposedly) causes weight gain because your body will constantly be in “fat storage mode” and rarely in “fat burning mode.”

It sounds good, but it’s a myth.

It’s true that insulin causes fat cells to absorb fatty acids and glucose and thus expand, but that’s not what causes you to get fatter over time…overeating does. (Click here to tweet this!)

If that doesn’t make sense to you, let’s quickly review how energy balance relates to fat gain and loss. Energy balance refers to the amount of energy you burn every day versus the amount you give your body via food.

  • If you give your body a bit more energy than it burns every day, a portion of the excess energy is stored as body fat, and thus you gain weight slowly
  • If you give your body a bit less energy than it burns every day, it will tap into fat stores to get the additional energy it needs, and thus you lose weight slowly

You see, any any given time, your body requires a certain amount of glucose in the blood to stay alive. This is vital fuel that every cell in the body uses to operate, and certain organs like the brain are real glucose hogs.

Now, when you eat food, you give your body a relatively large amount of energy (calories) in a short period of time. Glucose levels rise far above what is needed to maintain life, and instead of “throwing away” or burning off all excess energy, a portion is stored as body fat for later use.

Scientifically speaking, when your body is absorbing nutrients eaten and storing fat, it’s in the “postprandial” state (post meaning “after” and prandial meaning “having to do with a meal”). This “fed” state is when the body is in “fat storage mode.”

Once the body has finished absorbing the glucose and other nutrients from the food (amino acids and fatty acids), it then enters the “postabsorptive” state (“after absorption”), wherein it must turn to its fat stores for energy. This “fasted” state is when the body is in “fat burning mode.”

Your body flips between “fed” and “fasted” states every day, storing fat from food you eat, and then burning it once there’s nothing left to use from the meals. Here’s a simple graph from Weightology that shows this visually:


The green portions are the periods where your body has excess energy due to food having been eaten. The blue portions are the periods when the body has no energy left from food and thus has to burn fat to stay alive.

If the green and blue portions balance out every day–if you store just as much fat as you burn–your weight stays the same. If you store more fat than you burn (by overeating), you get fatter. And if you burn more fat than you store, you get leaner.

This is the fundamental mechanism underlying fat storage and fat loss and it takes precedence over anything related to insulin or any other hormones in the body.

Simply put, you can’t get fatter unless you feed your body more energy than it burns, and you can’t get leaner unless you feed it less energy than it burns.

It doesn’t matter how many carbohydrates you eat or how high your insulin levels are throughout the day–this is the first law of thermodynamics at work. Fat stores can’t be increased without the provision of excess energy, nor can they be reduced without the restriction of energy.

That’s why research has shown that so long as they’re eating less energy than they’re burning, people lose fat equally well on high-carbohydrate or low-carbohydrate diets. That’s why professor Mark Haub was able to lose 27 pounds on a “convenience store diet” consisting mainly of Twinkies, Little Debbie cakes, Doritos, and Oreos: he simply fed his body less energy than it was burning.

The bottom line is your insulin levels and the amount of carbs you eat have little to do with losing or gaining weight–energy balance is the key.

(If you want to know more about carbohydrates and weight loss, and when low-carb dieting is actually better, check out this article.)

Insulin Isn’t the Only Substance That Triggers Fat Storage

You already know that insulin causes fat cells to absorb glucose and fatty acids. Well, there’s another reason it’s charged with causing weight gain.

Your fat cells contain an enzyme called hormone-sensitive lipase (HSL), which helps break down body fat into fatty acids to be burned. Insulin suppresses the activity of HSL, and thus is believed to further promote weight gain.

Well, something carb- and insulin-haters like to ignore is the fact that dietary fat also suppresses HSL, and thanks to an enzyme called acylation stimulating protein, your body doesn’t need high levels of insulin to store dietary fat as body fat.

This is why you can’t just eat as much dietary fat as you want and lose weight. And why research has shown that separating carbs and fats doesn’t affect weight loss (eating carbs and fats together or separately doesn’t change anything).

Once again, it comes back to energy balance–regularly give your body more energy than it burns, whether in the form of protein, carbohydrate, or fat, and you’ll get fatter.

Protein Stimulates Insulin Production Too

This is another fact low-carb “gurus” like to avoid.

High-protein, low-carbohydrate meals can cause more insulin to be released than high-carbohydrate meals. Whey protein in particular has been shown to be more insulinogenic than white bread. Beef stimulates just as much insulin release as brown rice.

And in case you think the insulin response to protein is more moderate and prolonged (as if this were somehow better), it’s not–protein causes a rapid rise in insulin followed by a rapid decline, just like carbs.

Ironically, a high-protein, high-fat meal causes more immediate fat storage than a high-carbohydrate meal because dietary fats are stored very efficiently as body fat.

Insulin Doesn’t Stimulate Hunger–It Does the Opposite

This is another myth bandied about, but it’s been disproved by clinical research.

In fact, research has demonstrated that the more insulinogenic a meal, the more full you feel as a result. This correlates with research demonstrating that high-carbohydrate meals induce more satiety (fullness) than high-fat meals.

Insulin Helps You Build Muscle

While insulin doesn’t directly induce protein synthesis like amino acids do, it does have anti-catabolic properties.

What that means is when insulin levels are elevated, the rate at which muscle proteins are broken down decreases. This, in turn, creates a more anabolic environment in which muscles can grow larger quicker.

That sounds good in theory, right? But does it pan in out clinical research? Yes, it does.

There are several studies that conclusively show that high-carbohydrate diets are superior to low-carbohydrate varieties for building muscle and strength.

Researchers at Ball State University found that low muscle glycogen levels (which is inevitable with low-carbohydrate dieting) impair post-workout cell signaling related to muscle growth.

study conducted by researchers at the University of North Carolina found that when combined with daily exercise, a low-carbohydrate diet increased resting cortisol levels and decreased free testosterone levels. (Cortisol, by the way, is a hormone that breaks tissues, including muscle, down. In terms of maximizing muscle growth, you want low resting cortisol levels and high free testosterone levels.)

These studies help explain the findings of other research on low-carbohydrate dieting.

For example, a study conducted by researchers at the University of Rhode Island looked at how low- and high-carbohydrate intakes affected exercise-induced muscle damage, strength recovery, and whole body protein metabolism after a strenuous workout.

The result was the subjects on the low-carbohydrate diet (which wasn’t all that low, actually—about 226 grams per day, versus 353 grams per day for the high-carbohydrate group) lost more strength, recovered slower, and showed lower levels of protein synthesis.

In this study, researchers at McMaster University compared high- and low-carbohydrate dieting with subjects performing daily leg workouts. They found that those on the low-carbohydrate diet experienced higher rates of protein breakdown and lower rates of protein synthesis, resulting in less overall muscle growth than their higher-carbohydrate counterparts.

All this is why I never drop my carbohydrate intake lower than about .8 grams per pound of body weight when cutting (and yes I get to 6% body fat eating this many carbs per day), and I’ll go as high as 2 to 2.5 grams per pound when bulking.

Insulin Isn’t the Problem…Being Overweight and Sedentary Is

The bottom line with carbohydrate intake and insulin levels is this:

If you’re overweight and sedentary, regular intake of large amounts of carbohydrates is going to cause problems in the long run. Your body is going to have more and more trouble dealing with insulin, which can, over time, even develop into Type 2 diabetes, and you’re going to be at greater risk for heart disease.

If you stay lean, exercise regularly, and eat at least a reasonably sensible diet, you’ll never have these problems. You’ll maintain insulin sensitivity and your body will have plenty of use for the carbs you eat.


What did you think of this article on how insulin works? Have anything else to share? Let me know in the comments below!


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Leave a Comment!
  • Elt31987

    Another Excellent Article!

    • Michael Matthews


  • Justin

    great article i throughly apprciate the backing of proven research. i do have a few question i would like your opinion on though concerning high/low carb diets and those question are based around individauls body types. Ectomorphs, mesomorphs, and endomorphs
    i am personally a mix between a meso and endomorph.
    i have read hundreds of articles that state that endomorphs do much better at reducing body fat on a higher fat, lower carb regiment.

    I would like you take on this concerning high/low carbing and body types!

    • Michael Matthews


      I don’t know of any research backing up those types of claims. Some people’s bodies do better with carbs than others’, and some people seem to oxidize fats better than others, but I don’t know of any broad “body type” applications of these things. It’s really an individual thing.

  • YES! as it says in this article, OVEREATING is the root cause of weight gain. People have a million of excuses and insulin is just another whipping boy. Thanks for this enlightening article.

    • Michael Matthews

      Exactly! Thanks!

      • Alan Ege

        Mike I have finally began to learn it wasn’t the carbs that were killing me. It was the sedentary lifestyle. Now I am active and have begun eating more carbs and don’t get scared when I see foods that I have a higher carb count than I have been eating. Thank you for all your help in getting me started in this muscle building journey.

        • Michael Matthews

          Smart Alan. I don’t know how many people I’ve told just that: if you just moved your body more you wouldn’t have to worry so much about calories, carbs, etc.

    • Philip

      Check out “Why we get fat- and what to do about it. by Gary taubes. Then I think you will change your perspective on the subject.

  • Nathan

    I love how you make complicated things simple to understand. When’s Beyond Bigger Leaner Stronger coming out?

    • Michael Matthews


      Launch starts in a couple of weeks!

  • Luke Sfair

    Hey Mike, great article!
    what do you think about TNT Diet?

    Anxious for your new book!
    you’ll talk about periodization, right?

    • Michael Matthews


      Hadn’t heard of that until now but I just checked it out and it looks like another “carb timing” gimmick diet that overemphasizes the benefits of post-workout carbs?

      Just doesn’t matter that much.

      Yup! It’s launching in about 2 weeks!

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  • Marissa Georgiou

    Hi Mike, do most of these studies focus on males? Have you found that insulin response and the affect of carbs differ for females?

    • Michael Matthews

      No, they involve a combination of men and women. No, not particularly.

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  • Fakju

    Insulin tells your body to turn into “fat storage mode”but, there’s an another player in this game, his name is “glucagon”, it’s opposite to isnulin and that’s the point. Meat raises insulin + glucagon, carbs raises only insulin. No it really isn’t about how much calories can you burn a day. It’s about manipulating your hormones. Anyway you can just try it, Atkins diet. Just fats+meat = you can’t gain weight.

  • Nick

    Hey Mike, I recently changed my diet from a ketosis diet to a moderate-high carb diet. I am extremely active and know my macros well. I experienced about a 5 pound gain as soon as I made the switch. Would you assume its simply water retention? Is there any way to ease this?

    • Michael Matthews

      Yup that’s just water. Nothing to worry about.

  • Adel-Alexander

    Hey Mike, I was wondering.. I can’t really eat any Low GI-food at the moment due to my stomach not really handling insoluble fiber that well, so I actually try and opt for white rice instead brown rice etc etc, but I was wondering if there was something for me to do? Can you recommend some low GI foods but with a relatively low amount of fiber maybe?

    I usually have lots of energy, but I have to admit I have been struggeling a bit in the gym now and I don’t know if I should replace my current carbs, or just increase my calorie intake. Any ideas?

    • Michael Matthews

      Ah okay. White rice will be fine if you’re exercising regularly but I would recommend you get a variety of carbs.

      You can look into various fruits and veggies. Some have less fiber than others. Legumes and tubers too.

      How are your macros?


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  • Drew

    Thank you very much for this article. I have been doing keto and lost 30 pounds but now I bought your book and decided to follow what you have there. I have a question though, what is the best way to transition from keto to normal/high carb diet? I don’t want to get all my weight back!


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  • Andrew

    Hi Mike,

    I have scoured your website and BLS to get a clearer answer on if eating high GI carbs will cause significant issues in either losing fat or building muscle?

    The issue here is that my family owns a potato packaging/distribution warehouse so I can get potatoes very cheap, and I love potatoes (standard brown russets).

    Will eating these on a daily basis really hurt my progress as long as I control my macros and calorie intake levels?

    • Michael Matthews

      Hey Andrew,

      Short answer: no, it won’t. I love potatoes too despite the fact that they are incredibly high-GI when baked.

      You’ll be fine.

      • BoandTanya Krop

        Boiled potatoes were rated higher than lean proteins on the satiety index with a score of over 300%. Cooled boiled potatoes (like potato salad) should be very low glycemic (I would presume) due to their very high resistant starch content.

        • Yeah they’re great for satiety and you know I’m not sure if GI would come down as they cool, as they are changed through the cooking process.

          Either way I wouldn’t worry about the GI of potatoes unless you were eating absurd amounts of them every day.

    • BoandTanya Krop

      I’m curious about your perspective on de novo lipogenesis being quite low on those eating high carb diets. Indicating that carbs are inefficiently converted into stored body fat even if consumed above calorie needs. What do you think? Are carbs almost always exclusively oxidized except in very rare over feeding experiments? And is the fat you eat really the fat you wear (to paraphrase Dr. McDougall of The Starch Solution)?

      • Generally speaking yes DNL costs about 25% of the energy contained in the carb but ultimately how well your body is at oxidizing vs. storing comes down to current circumstances and genetics.

        Some people DO gain more fat from overfeeding carbs than others.

        Same goes with dietary fats, even though they’re much more easily stored as fat.

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  • Thanks for stopping by and checking out my article! I hope you enjoyed it.

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  • davehorne

    If you eat exactly the number of calories to maintain your weight – not get heavier or lighter – _and_ if I inject you with insulin with every meal, you’ll get fat.

    How do you explain that?

  • ankita

    U Mentioned 20 % Carbs intake in one of ur articles.for fat loss nd here u say 0.8 g per lb body weight.which shd b followed?

    • Vladimir Lialine

      Great article. The info is correct, but incomplete. Fat and protein calories require a tremendous energy expansion. Upto 50% of its energy is used in metobolic processes, where simple sugar requires almost no calorie expansion to be digested. When you eat heavy your blood sugar drops, which will trigger cortisol release. Maintain steady blood sugar levels with simple carbs and your metabolism will sky rocket…

      • That’s not true. The thermic effect of dietary fat is actually quite low. Carbs cost about 25% of energy to digest and process.

  • ScarlettDuchess

    I had severe insulin resistance and I never overate due to a poor appetite. I only lost weight when cutting out the sugar in my diet.

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  • Megha Bormudai

    I get so happy just by reading your articles. It’s like… a great stress free environment that creates around me when I read them. And I get all boosted as I know what is the real factor helping in my weight loss and muscle build up. Must say AMAZING… and yes THANK YOU.

    • Happy to hear you’re enjoying the articles. 🙂

      LMK if you have any questions.


  • Mandrakora

    ” This correlates with research demonstrating that high-carbohydrate meals induce more satiety (fullness) than high-fat meals.”
    I liked your article, but I think you have to be very specific while talking about the carbs you are eating, its not the same a High carb diet from junk food, than from fruits and whole cereals.
    If you are on a high carb diet from junk and processed food, you´ll be creating and adiction on high sugar foods and binging on those foods, so you wont feel full for a long time. You´ll also be overstimulating the reward system on the brain, and affecting leptin hormone.
    Thanks for your work!

    • Thanks for the comment! That’s true to a point but it depends what you consider “junk” and “processed” foods…

  • Rajeev Samuel

    “Insulin Triggers Fat Storage…But It Doesn’t Make You Fat”

    Michael Matthews really? I have been on the ketogenic diet for over a year now and I have to say without a doubt that carbohydrates trigger insulin and make you fat.

    There are only four grams of glucose in the bloodstream. If it goes to six you go into a diebetic coma and die – do you really want to eat carbs now?

    • Did you even read the article?

      Also relevant:


      • Rajeev Samuel

        Did YOU read my comment about the four grams of glucose in your bloodstream? Do you understand what a control system is? You eat 500 grams of carbs in the form of rice. If your glycogen stores are full it gets converted into fat. Look at the obesity crisis and you are going to tell me in good concious that I’m not right really? The energy balance theory of thermodynamics can only be applied to components with single control systems like car engines (which only control one fuel source – gasoline) not humans (which have five sources of fuel – alcohol, fructose, glucose, glutamine, fat).

        Fyi – when I put myself in keto I do HIIT and deadlifts everyday to get there faster – weekends socializing is tough to avoid alcohol and carbs. Thank god for C4. I tried bringing grains back into my life over the summer and I gained 15 pounds. And it’s protein that induces satiety(fullness) not fat.

        • So much wrong here but honestly it sounds like you’ve already made up your mind so believe what you want.

          Just know you’re making things far more complicated than they have to be.

          • Rajeev Samuel

            Well I say you are a liar and a dumbass. When you get an engineering degree and take a course called thermodynamics you will be allowed to tell me that I’m wrong 🙂

  • Ozan

    Hello. I am 32 years old insulin sensitive man. For 2 years I am lifting weights 3 to 5 times a week. Trying to eat as much as healthy I can. But my muscles are neither growing nor I am getting any stronger. I am taking mutli vitamins, fish oil in the morning. Amino acids and bcaa during workout. Whey protein after work out. Creatine and glutamine post workout and casein protein before sleeping. I am avoiding carbs etc. But the improvement of my body is very very slow. Do you have any recommendation for me.

  • Arnq

    Wow, so you’re saying that a prediabetic or diabetic person can eat all the bread or pasta they want and it will have zero effect on their weight gains or losses? That’s just not true. This post refers only to insulin sensitivity in normal people. People who have insulin resistance or prediabetes and those with diabetes maintain higher levels of insulin for longer than a normal person would, so their fat loss due to reduces insulin is decreased comparatively. Also due to the over production of insulin they store more fat than a normal person might in the first place, meaning that less of it makes it’s way out of the body. Not everyone absorbs the same amount of cals from the same meal, some people pass some of those cals out, others absorb them all. The same is true for fats. Now back to the claim that there is no connection between carbs, insulin, and weight gain… you yourself have contradicted this many times in other places on this site. I know that most of this information is geared to normal healthy people, but there is little to no information out there for insulin resistant people to go from being in an unhealthy to a healthy state, sometimes they land here, lured by the fact that you actually sound like an informed individual, but all they find is ‘no you don’t have a legit illness, you’re just a fatty that can’t keep their mouth shut.” Super hash man.

    • When metabolic disorders enter the picture, things change. I talk about this all the time, lol.

      That said, things don’t have to change as much as some people think. I’ve worked with thousands (literally) of very overweight people that have done fantastically well with a high-protein, high-carb diet that was laid out properly.

      You can find plenty of examples of the same in the literature.

    • Andrei Jerdetski

      Well said, couldn’t agree more. “you are fat because you overeat, so its your flault” is what i got out of the article, which is plain wrong and relying on several limited studies is somewhat absurd. Ketosis (a term you failed to mention even once) is proven to make people loose weight and im sure you know a human body gets into the state of ketosis. In the comments below some just said they gained 5 pounds when they switched to higher card diet. Water retention, are kidding me, 5 pounds? You have to understand that not only healthy insulin tolerant people will look at this article, truth is A LOT on people are very sensitive and not necessarily diabetic.

  • amanda

    I have learned so much from you’re writing – it’s my go to when I’m looking things up. THANK YOU SO MUCH! !!

  • waleed arda

    I couldn't agree with you more.  Insulin is not a third party playing by its own rules. It conforms to the nature of the meal and removes the trafficking nutrients to their targeted stores.  In that sense it should be looked at as Blood clearer rather than cell's opener. Insulin serves to keep all the nutrients in their stores and regulate their reentry to the blood in a orderly fashion. If it weren't for the insulin; the blood would be fully saturated with glucose and fatty acids waiting to be used as energy but wreaking havoc on blood vessels. Insulin resistance is a normal healthy response where the body needs more insulin to keep the fat in place but less insulin to avoid hypoglacemia. The body  to induce IR to do this brilliant  trick. The only problem  is when the pancreas reaches its full capacity and can no longer satisfy bodily requirements of insulin, and this is when diabetes comes to surface.

  • Andrei Jerdetski

    Everything you say in your article has been disprove by extensive research (apart from insulin for muscle growth)

    ‘Once again, it comes back to energy balance–regularly give your body more energy than it burns, whether in the form of protein, carbohydrate, or fat, and you’ll get fatter.’

    In the classic force-feeding studies, volunteers can be made to gain weight in the short-term by massive overfeeding. However, the body responds dynamically: the volunteers lose all interest in food and their metabolic rate tends to increase in the body’s attempt to burn off the excess calories. Indeed, volunteers in overfeeding studies characteristically report feeling intensely uncomfortable. Once the protocol ends, weight typically decreases back to baseline [Leibel, Roberts, Norgan, Sims] — a phenomenon that has also been well documented with experimental animals. Consistent with the Insulin-Carbohydrate model, the metabolic responses protecting against long-term weight gain with overfeeding may not fully engage when excess calories are provided primarily as high glycemic load carbohydrate (candy) rather than protein and fat (peanuts) [Claesson].

    ‘Insulin Doesn’t Stimulate Hunger–It Does the Opposite’

    The metabolic problems following a high glycemic load meal occur several hours after eating. The review by Guyenet from 20 years ago examined glycemic and insulinemic responses 2 hours after the meal. As extensively reviewed [Ludwig], the metabolic problems with high glycemic load foods emerge in the late postprandial period (after about 3 to 5 hours), when availability of metabolic fuels is reduced [Ludwig, Walsh, Ludwig, Roberts]. Analyses that fail to distinguish between early effects (when blood glucose surges) and later effects (when metabolic fuels decrease) will be uninformative

  • Andrei Jerdetski

    Ok here we go.

    ‘Once the body has finished absorbing the glucose and other nutrients from the food (amino acids and fatty acids), it then enters the “postabsorptive” state (“after absorption”), wherein it must turn to its fat stores for energy. This “fasted” state is when the body is in “fat burning mode.”’

    The problem is that the body will enter into fat burning mode as you call it much later as the glucose levels in blood remain elevated for longer from carbohydrate rich meal http://www.ncbi.nlm.nih.gov/pubmed/23483989 , low carb meal (60% fat 10% carb) and it is not only until 180 minutes after the meal when carb rich food finally catches up. Which is when referring to your own word will mean that so called fat burning mode will happen much later when compared to high fat meal.

    ‘Well, something carb- and insulin-haters like to ignore is the fact that dietary fat also suppresses HSL, ‘
    Perphaps, but the true effect of the study requires further research, the subjects were not given proper meals not even junk meals.

    ‘Protein Stimulates Insulin Production Too’

    Agree with you on that with a big BUT protein stimulates the release of Glucagon while carbs do not. There is a positive link between Glucagon and satiety, i.e. you stay fuller for longer.


    ‘Insulin Doesn’t Stimulate Hunger–It Does the Opposite’

    Wrong. The study you are referring to looked at 4 hour interval. A quote from Dr Ludwig:

    As extensively reviewed [Ludwig], the metabolic problems with high glycemic load foods emerge in the late postprandial period (after about 3 to 5 hours), when availability of metabolic fuels is reduced [Ludwig, Walsh, Ludwig, Roberts]. Analyses that fail to distinguish between early effects (when blood glucose surges) and later effects (when metabolic fuels decrease) will be uninformative.

    Further to support this refer to http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3590159/figure/pone-0058172-g002/, low fat high carb meal had the highest hunger rating, the food that spiked insulin the most (the same link).

    and finally

    ‘It’s true that insulin causes fat cells to absorb fatty acids and glucose and thus expand, but that’s not what causes you to get fatter over time…overeating does.’

    While this study http://www.ncbi.nlm.nih.gov/pubmed/19396658 compared one extreme with another (candy and peanuts), showed that carb diet had more negative effect on metabolism. To expand on that i will quote Dr Ludwig once again

    In the classic force-feeding studies, volunteers can be made to gain weight in the short-term by massive overfeeding. However, the body responds dynamically: the volunteers lose all interest in food and their metabolic rate tends to increase in the body’s attempt to burn off the excess calories. Indeed, volunteers in overfeeding studies characteristically report feeling intensely uncomfortable. Once the protocol ends, weight typically decreases back to baseline [Leibel, Roberts, Norgan, Sims] — a phenomenon that has also been well documented with experimental animals. Consistent with the Insulin-Carbohydrate model, the metabolic responses protecting against long-term weight gain with overfeeding may not fully engage when excess calories are provided primarily as high glycemic load carbohydrate (candy) rather than protein and fat (peanuts) [Claesson].

    • Thanks for the comment!

      Playing poker with studies (“I’ll see your low-fat, high-carb study and raise you two low-carb, high-fat studies!”) is silly and gets nowhere.

      What is your point/position?

      • Andrei Jerdetski

        My point is no dietary argument is black and white and also that the traditional “calorie in, calorie out” diet is outdated. “You are getting fat because you overeat” is the excuse used by junk food companies for decades. Coca-Cola recently “donated” to a research which would support exercise over a diet. http://www.smh.com.au/business/consumer-affairs/what-cocacola-isnt-telling-you-about-its-health-funding-in-australia-20160217-gmx3l3

        Yes, your body needs to burn more energy than it consumes to lose weight, no question. Calorie in, calorie out approach should be easiest way to shed killos, so is the lack of will power to blame for the obesity epidemic? We are consuming more calories from carbs (and most highly importantly processed carbs) than ever in the human history.

        The research I cited supports an argument that insulin spiking carb foods make you hungrier over the long term [emphasis added] and fighting the hunger will only slow down your metabolism, meaning your body will be burning reduced amount of calories on idle, so you have to eat even less BUT your brain will respond by slowing down the metabolism even more. Unless you got an incredibly strong will power, you will give in to hunger and chances are you will reach for that highly process piece of carb thus starting the vicious cycle again.

        This is not so much of an issue for a fitness freak who will work out and use the blood glucose from carbs very quickly, hence entering into ‘fat burning mode’ quickly. Building muscles with carbs for that person is hardly a hurdle. But what about an office clerk on 50 hours working week (as I am for example), 3 kids and little or no time to exercise, I’m still relatively young (early 30s), no diabetes and can still force myself to exercise at 10pm when kids are asleep.

        I can speak from personal experience that high fat diet decreased my long term hunger (by high fat I mean 50%, 30% low GL carbs, and 20% protein) when I started it I was 91kgs and 180cm, now I’m 85kgs and have no idea how many calories (because I stopped counting) are in my meals, my life style otherwise stayed exactly the same.

        • Alok Mishra

          So as if I ask you about my meal plan what it should be? Low carb high protein or high carb high protein or high carb low protein. Being 85kg and I am 25.

        • That’s great you’ve found something that works well for you but keep in mind I’ve worked with thousands of people and am speaking from that experience.

          If someone is overweight and sedentary, low-carb is a good call. Carbs are primarily energetic so if you’re not burning a lot of energy, you have no need for them.

          If someone is exercising regularly, though, and especially if they’re lifting weights regularly, they are probably going to have an overall better dieting experience on a higher-carb diet.

          • Jo Mormont

            I agree with you but what does higher carb actually entail? How many grams of carbs are we talking about here ballpark wise as far as macros are concerned?

          • Eh yeah around there. I consider .5g/lb of bodyweight or lower low-carb dieting.

        • JML

          Really appreciate your comments. Context is key to proper comprehension.

        • The Poetry Lady

          Andrei, you have managed to explain my life! I’m joking but I’m not. You have shared the only plausible explanation I’ve found as to why the calories in calories out regime ends up backfiring on me after I’ve cleaned houses all day and burned 700+ calories, yet still have a slow go at not only losing weight but sticking to the regime.

        • Jerome Bryson

          Exactly. An outdated and incomplete explanation. I hope people can grasp this…even the ones that seem totally EDUCATED on the subject. But the 1st Law of Thermal dynamics has everything to do with PHYSICS, NOT PHYSIOLOGY. The food industry…the health industry have all used this application for decades. And you wanna know what has happened over those decades? An gargantuan rise in diabetes and obesity. So please, stop shoving this know-it-all/matter of fact knowledge down our throats.
          Some of us know a whole hell of alot more about how this all works now.

  • Forrest

    Can you explain why type 1 diabetics who don’t get insulin waste away, but those who do gain weight? There is now a phenomenon known as Diabulimia which describes type 1 diabetics who purposely don’t take their insulin to lose weight. This is regardless of how many calories they take in. This at least points to a correlation, if not causation, that insulin is a dynamic player in weight management, unless you know something I don’t?

    • I’ve worked with quite a few people with T1D that don’t experience any of that. They do quite well, actually.

  • Hey Mike! Awesome article.
    Question I have after reading this is, if Whey protein spikes insulin levels, is it preferable to not have a shake before a workout and just take BCAA rather for pre-workouts, and just get more of a natural protein from Fish, meats etc? Or is it a case of using whey moderately to maximize protein synthesis? Thanks in advance!

  • Darth Folwart

    Pseudoscience. Sit down, quit posting.

  • Erik Rokisky

    Hey mike, check out the insulin and serotonin relationship! I think it might interest you.. great article! http://journals.plos.org/plosbiology/article?id=10.1371%2Fjournal.pbio.1000227

  • Jay Vincent

    okay you are missing one huge point here. What makes us sedentary and fat? Chronically elevated insulin does. When insulin levels are spiked, the result is insulin resistance. Insulin resistance causes internal starvation of the muscle cell. This causes a majority of the calories you eat to be shunted to body fat rather than lean tissue which is essentially causing your body to starve. In order to survive, the body “thinks” it must eat more (gluttony) and move less (sloth) to provide enough survival energy for lean tissue.

    Elevated insulin levels also inhibit Ghrelin and Leptin from reaching the hypothalumus Ghrelin tells you when youve eaten enough and to stop eating. Leptin signals your body to stop storing energy and fat cells and to burn it. (The cost of carrying the extra weight out-weighs the benefit ofextra energy reserved).

    This is the cause of fat storage and the obesity epidemic. not too many CARBS, but too much SUGAR and REFINED CARBS. Carbs which contain fiber slow the rise in blood sugar and are great to eat. So carbs should not be villianized, but foods with a High Glycemic Load should.

    • Jay Vincent

      I’d like to make one more compelling point that might seem interesting. Our metabolism evolved over what… 1 million years or so? It evolved based on what is available in our environment. If you were to hunt/gather food as all animals did over the course of that period of time, what would they find? Meat, a small amount of fruits and berries (when they’re in blood), some veggies depending on availability and a lot of calories would come from meat fat. The least abundant macronutrient you would find is carbohydrate, and NO refined carbohydrates.

      This is the first time in evolutionary history where carbohydrates (more specifically refined carbs and sugar) are abundant and excessively eaten. Our metabolism is not involved to accommodate this huge amount of glucose. In response, we become fat, insulin resistant, chronically inflamed and sick. If you plot a chronological curve of average carb intake vs obesity rates over the last hundred years, they go hand in hand.

      If anybody can find a logical counter argument, please feel free to share. But to me, it’s obvious.

      • The Paleo mythology makes for good marketing but not good science. I talk about it here:


        And again, these articles are relevant:



        • BoogerSanchez

          Neither is your stuff. Calories are not anything. Energy is simply a number as Alan Guth notes.

        • Emmie

          The Paleo mythology really is exactly that, a mythology. As an Archaeologist I can clear this up. The only reason we think cave man ate a lot of meant is purely based on Hollywood and the fact that bone survives in the archaeological record wheras organic matter does not. Ancient man survived on a diet of legumes, pulses and berries.

      • Josie Q

        Everything you say is true, Jay. Mike is an idiot and his article is shit.

      • Jess Walters

        I totally agree with you. This is what I studied in my human metabolism class. Calories in vs. calories out is not the best way of looking at fat loss. The human body varies and does not exactly follow the laws of physics. To look at weight loss…the laws of biology need to be looked at. While yes, eating less calories can lead to weight loss for many it can slow the metabolism down and once people start eating more calories…that are supposed to be maintenance level they start gaining weight again. The quality of the calorie does make a difference and hormones play a huge part in fat gain and loss.

      • Honey has been eaten for a long time.

        Cave paintings in Spain from 7000BC show beekeeping. Fossils of honey bees date back about 150 million years.

        So people have been eating carbs for a long time.

        And it’s over ⅓ fructose.

      • Sheri Knauer

        I agree with you Jay. It only makes sense. These refined carbs and sugars were pushed on people and being touted as convenient, affordable, and good for you by the govt, food (mainly big oil and sugar) and pharmacy industries and eggs, fat, butter etc were vilified by shoddy manipulated studies funded by these same people who want to make a profit from selling there fake food manufactured in their factories. And lets not even talk about all the physicians who don’t care to do any kind of research regarding diet and nutrition and go by what they learned in chapter 6 in medical school 30 years ago. All a lot of them do nowadays is if you have a symptom, prescribe a pill. Tell them to eat low fat and high carb, they get diabetes. Prescribe more pills and tell them they eat too much, they eat less and continue to gain weight and diabetes gets worse, prescribe more insulin and tell patient they must not be eating the right foods (when they are or at least what they are told are the right foods). prescribe more insulin because we all know the best thing to do when you are insulin resistant and have too much insulin in your blood is inject more into it. Tell your patient that there is nothing that can be done, its their own fault for not following their advice about what to eat, that diabetes is genetic and progressive and just start saving up for your funeral…………….

      • Casadejoe

        Well said. Once I started to treat insulin as the main culprit I was able to lose weight and get off my insulin. Being overweight and grazing throughout the day keeps ones insulin level high, which promotes fat storage. LCHF works well for me along with an 8 hour feeding window. I wish more people would at least give it a try before they knock it down.

  • Daniel Breez

    This article talks primarily about the effects of insulin on weight gain or loss, and how it is not relevant to MOST relatively lean people in terms of gaining or losing fat. BUT, there are certain conditions that people have which do make it harder to lose weight with a high carb diet. Do you have any knowledge on women with PCOS? From what I’ve researched, they are very insulin resistant and will do better with a high fat/low carb diet.

    • That’s true. There are certain medical or physical conditions where people won’t do well with carbs. Generally speaking though, if you’re a healthy adult that’s active, lean and sticks to a reasonably well-balanced and nutritious diet, carbs won’t be an issue.

      I talk more about this here:


      LMK what you think!

  • Greg Mueller

    What you eat, not just how much, impacts how your body partitions and stores fat. You are missing a key nuance of the first law of thermodynamics as it applies to fat storage. I recommend you read this article and skip to concept #5 if you want to get to the point.


    • That’s true to a point, but it doesn’t negate energy balance.

      I talk about nutrient partitioning all over the place, but here’s a good primer:


      • BoogerSanchez

        Stop abusing energy. Energy is not itself ANYTHING. CALORIES DO NOT EVEN EXIST.

      • BoogerSanchez

        As Feynman said you cannot use energy, an abstract mathematical fiction as ANY KIND OF EXPLANATION FOR ANY PHENOMENON. CALLING YOUR ANTI-TAUBES BULLSHIT OUT!


  • Cleethorpes

    Raising insulin raises IGF-1. Protein raises insulin too, but high glycaemic carbs are the worst offenders. No matter how satiating some people report insulin to be, the effects of IGF-1 on chronic health are detrimental.

    • IF you’re sedentary, sure, as IGF-1 makes everything grow. But if you’re physically active, and especially if you train your muscles regularly, IGF-1 is your friend.

      • Taylor Kuzik

        How active are we talking about here? I workout 5-6 days a week with 1 rest day. I don’t do a low calorie diet because that is a recipe for disaster. I have a physical job Monday-Friday for 4 hours that involves pushing and lifting of various weight. That hourly shift goes up during Christmas shopping.

  • Samuels90

    Hi Mike,

    Im curious, when you are cutting to 6% how much protein would you take in and how much dietry fats?

  • Martin351

    You are so far off the mark it’s not even funny lol. You are missing a very big piece of the equation, in fact 50% of it; fasting insulin levels. Not only that your “overeating” cause of weight gain is completely off the mark as well and has been refuted in 75 years of studies.

    So fasting insulin, what is it you ask Mike? Well what does it sound like? Baseline insulin levels taken while fasting. Everybody has a fasting insulin level; there is always insulin floating around in the body, but obese people have HIGHER levels.

    When someone eats their fasting insulin level is multiplied by 5-7x, and a good or desired fasting level is somewhere between 3-8 micro-grams. So a person with a low fasting insulin level (lets say 5 here), will eat and it will multiply their sinulin up to 25-35 micro-grams. This is still relatively low, and it doesn’t have far to go to get back down to baseline. The main point here is the baseline insulin is low, therefore the body has more access to it’s fat stores, simple as that.

    Now someone who has insulin problems (which is evident with obesity), might have a fasting insulin level of 30-50 micro-grams. Using 50 as an example, multiply that by 5-7x we get 250-350 micrograms. Insulin is far too high completely blocking fat burning. Not only that, their fasting insulin level is also to high to adequately dip into their fat stores so the fat remains. This is exactly why some people who restrict their carbohydrates still can’t lose weight, their fasting insulin level is far to high.

    This is only alleviated by fasting or extended fasts, and no this is not caloric restriction. The way your body treats caloric restriction is far different than avoiding food. When it caloric restricts, it simply re-adjusts it’s metabolism for the amount of calories taken. Drop from 2000 to 1200, fine, the body simply drops the metabolism down to 1200. Either way, food is coming in so it’s happy.

    Fasting on the other hand it treats different; metabolism doesn’t slow, it stays the same and even amps up. This is natural when you think about it from an ancestral standpoint, your body sees no food coming in so it must keep the energy level high so you can go out and kill that animal and get some food. If one fasted, the body is not stupid, and just allow it’s energy to deplete to 0, stopping someone from acquiring food.

    Either way, no matter how you look at it, it’s insulin, it has everything to do with insulin. People who are shredded and cut up, have low fasting insulin levels. Obese people and the average person will have higher levels; anybody can test it, and anybody can see the correlation.

    Your over eating assumption is flat out wrong. There are many people (me included) who stalled and gained weight eating 1200-1500, but then lost weight rapidly when caloric intake was quadrupled to over 6000 calorie daily.

    Caloric output is what counts and it does not stay the same on a caloric restrictive diet. Come on, you have to give the human body more credit than that; it knows exactly what you’re doing. Think of it this way, if you make $100,000 annually and spend $100,000 annually; if you suddenly made $50,000 annually, would you continue to spend $100,000 or lower it to $50,000…

    Think about it, nobody is that stupid, and neither is the human body.

    • PaulfromWal

      Well said, and I wish these “fitness experts” would start using a little common sense here. Of course someone with a low fasting insulin can eat nearly anything they want and calorie restrict or over-consume and it will have little effect on their weight. It may bounce up and down, +/- 5lbs.

      For other people, this isn’t the case. The average person will have higher fasting insulin levels to begin with, and as you said, obese people’s levels will be even higher. You can’t tell an obese person to simply eat less and move more, because their metabolism will simply drop. This has been proven over how many decades ago? There is a 99% failure rate with CICO dieting.

      Bottom line, a person with lower fasting insulin levels will have better access to their fat stores and better blood sugar control. A life time of carbs and watching calories will change this from the worse due to carbs effect on insulin levels, and cortisol’s affect on blood sugar. Caloric restriction causes elevated stress hormone, and in obese people, the amplification of this is larger.

  • BoogerSanchez

    You, Mike Matthews are a physics illiterate charlatan salesman. Stop abusing physics. Can we infer the behavior of mammalian fat cells from the conservation of energy principle? THAT ANSWER IS HELL NO.Obesity is very poorly understood and fat cell dysregulation has unknkwns and uncertainty the size of the Pacific Ocean….. Fat cells are goberned by HORMONES-STUFF. ENERGY IS NOT AT ALL A THING OR STUFF OR ANY KIND OF CONSTITUENT OF THE UNIVERSE. PURWLY ABSTRACT MATHEMATICAL FICTIONL NOTHING MOREL USEFUL, BUT ONLY A NUMBER. ATOMS ARE AN ACTUAL ENTITY.

    Energy is NOT itself anything, you retard. Energy is merely an abstract property , a chacrgeristic of actual stuff, oike ATOMS.











    Even quntum field theory may he i error in the future , fool. Yiu habe NO BASIS for your certitude. WE DO NOT UNDERSTAND OBESITY AND HABE NO EFFECTIVE TREATMENTS CURRRENTLY.

    I have talked to physicists about thjs and they DO NOT agree with you or Krieger at all.

  • BoogerSanchez



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