How carbs make you fat

Carbs are killing you

Despite the slightly too wild headline this is a nice new infographic about carbs, insulin and obesity. It’s simplified of course – it focuses only on the peripheral effects of insulin: growing fat cells.

Chronically high levels of insulin also induces something called leptin resistance in the brain. What that does is basically make the brain blind to the fat stores, so that the brain can believe the body is starving even when it’s really obese. It’s a double whammy.

The easiest way to become obese? Eat more (bad) carbs than you burn. Eat at McDonald’s for example and choose extra-large fries and a large Coke (starch and sugar).

For a slightly more advanced lesson see my 15 minute interview with professor Robert Lustig: The Cause of Obesity.


  1. Alexandra
    This is great poster that should be displayed in schools, gyms and doctor's offices. My only quibble is "You think of meal containing carbohydrates." Isn't the body's reaction the same no matter what sort of food you think of? Because, if so, it gives the appearance of an irrational demonization of carbs - exactly the same thing that was done with fat.
  2. Frank
    I was worried about that, too.

    There is a danger that people on VLC diets may start to think that their extreme form of glucose intolerance is common to everybody (Tom Naughton is a case in point).

    A simple guideline like '50-100g of safe starches/day' will be a lot more helpful than variations on religious taboos a la "Are you thinking of EVIL CARBS again ?"

  3. Jeem
    It's odd that the info-graphic shames starches, liquid carbs, and stuff made of flour, but not sweets. Where should sugar be on the "worst offenders" list?
  4. Jaime
    True: there are people who survive throughout the day with chocolate bars, plus almost every single product -including items as unlikely as sausages- are packed with either sugar or high fructose corn sugar. Ketchup, for example, can have as much as 25-35% sugar (or HFCS).
  5. Alexandra
    OT tech question - has anyone tried to download The Eatery app from Massive Health (the people who produced the graphic)? It looks good, but I keep getting a message that I need iOS 4.2 or later, and my phone is already on iOS 5.0 something. There doesn't appear to be a way to contact them.
  6. Slightly simplistic but quite educational.
  7. moreporkplease
    I agree with Alexandra - but I don't think it's a quibble. The graphic really needs to be corrected.

    The emphasis is on the moral, not the physical. It's your *thinking* that's making you fat! Blaming the dieter is still step 1 here.

    If we think about steak, do we then not secrete insulin? I mean, their heart's in the right place, but it's a serious inaccuracy. The graphic would be much stronger if it were factually and physically correct. :)

  8. I came across your blog when I was trying to read my way through the Gary Taubes vs Stephan Guyanet blog wars. Im a huge fan of Gary Taubes and he offered the first explanation that made sense to me of why we get fat. It was very disheartening reading Stephan try to debunk it. I came to the conclusion that both theories do not need to be necessarily mutually exclusive. It would seem clear that the brain has some input into our fat gain, but also something has to be happening at the fat cell and as food comes into our bloodstream.

    All I know is that I am no longer feeling hungry anymore and I feel my weight may be under control. I have Gary Taubes to thank for that. But you were the one voice of reason that gave me a little bit of hope too while I was reading those comments. So many people just praised Stephan but there were some obvious inconsistencies. The main one for me was that it is no surprise that in the brain insulin reduces hunger - thats what it should be doing....IN THE BRAIN. Same goes for increased Leptin with increased Insulin - it makes sense that your body is trying to stop you from eating.

    Anyway enough babbling. Glad I found your blog and will be reading from now on.

  9. Alexandra
    "The emphasis is on the moral..."

    Exactly! The last thing we want is another religion.

    "The graphic would be much stronger if it were factually and physically correct."

    Yes. What I want to see is a dispassionate weighing of the evidence - not propaganda of a different variety.

  10. Murray Braithwaite
    I am not sure the statement that thinking about carbs triggers insulin. When our dog knows a treat is coming, drool literally drips from his mouth. We know sugar has an effect on the dopamine centre in the brain similar to nicotine, cocaine and morphine. This is likely due to the psychotropic effects of the blood sugar high. Meat does not cause a blood sugar high and I have not seen a study suggesting addictive properties of meat.

    We also know that when the mouth detects sugar in the mouth this starts the secretion of insulin. Meat does not.

    Perhaps the graphic should be amended to state that for some people, the thought of carbs triggers insulin. Just as for some people, the thought of a cigarette triggers a craving.

  11. moreporkplease
    "I am not sure the statement that thinking about carbs triggers insulin."

    Well then, the new treatment for T2D and obesity is simply to not think about the carbs you are eating. We should just tell people to watch exciting sports events on TV while eating carbs, and that way they won't think about carbs, and thus won't spike their insulin. All fat people need to be lean is *distraction*!

    Now I can go back to eating 6,000 calories of potatoes washed down with Coke a day in the full knowledge that my insulin won't rise and I won't gain weight.

    I hope you realize this is a reductio ad absurdum.

  12. Hi Alexandra,

    Are you still experiencing problems downloading The Eatery? We'd love to have you join The Eatery community. Please drop me a note at so we can figure out the problem if you're still experiencing problems. Thanks and I look forward to hearing from you!

    Warmest regards,

  13. Sp
    So, I've being reading this blog for a long time, and while it state how we get fat, It never state how to get slim. You think those two would be the same, and they should be, but somehow they aren't... Am I making any sense?
  14. Alexandra
    "It never state how to get slim."

    Here. Do this. :)

    •Eat: meat, fish, eggs, vegetables growing above ground and natural fats (like butter).
    •Avoid: sugar and starchy foods (like bread, pasta, rice and potatoes).

  15. Personally, I found the poster a little confusing. The top spends a lot of time on the secretion of insulin, yet there is a disconnect between steps 9 and 10--carbs->insulin, carbs->insulin, carbs->insulin, all of the sudden fat? HUH? Toward the bottom it finally explains "when insulin levels go up, we store fat", but steps 9 and 10 at the top seem to say that fat you eat still makes you fat.

    It could be clearer and more simplified, since it is meant to speak to people who haven't read Atikins, Taubes, etc and still think "calories in, calories out" is meaningful.

  16. Alexandra
    Thanks Cassandra!
  17. Think about taking the first bite of your favorite food: the mouth waters in anticipation ala Pavlov, and I feel strong elevation of desire for that food. My understanding is that the anticipatory mecahanisms in the brain do ready the body for food which means along with saliva there is some insulin released, among other things. Would be nice if we could reverse the insulin with thinking, but the primitive part of the brain seems immune to thought. Try to wish away the need to urinate, for example--I've tried mant times. I doubt it would be as much a reaction to foods that don't overly stimulate insulin production. I know that I feel a dfferent sense of anticipation with starch/sweets than a juicy steak, which I love, too.
  18. John
    This poster could not be anymore incorrect.
    1.) Eating protein causes an insulin spike
    2.) Dietary Fat requires nearly zero energy to convert to fat
    3.) Leptin resistance occurs due to chronically elevated levels of leptin as in the case of a obese individual, much like insulin resistance is caused by chronically high levels of insulin.
    4.) Fat oxidation after a meal is only temporarily put on hold until the calories from the meal are used, this stands true despite what you are eating.
    5.)Fat stores itself with tremendous efficiency without insulin, due to acylation-stimulating protein (ASP).
    6.) High levels of insulin are the result of obesity. They aren't the cause of obesity.
    ....i could go on and on, it's calories and it's always been calories. There is no magic diet to make you skinny. I have maintained 8 percent body fat eating potatoes, pasta, rice, and even beer. I eat these things on a daily basis, so don't be fooled
  19. Cat
    That poster is correct, only partially, because it DOESN'T talk about fat.

    In response to John, I have some comments to make.
    1) Eating protein does spike insulin, but it also makes glucagon, cortisol, and CCK to go up too. I have read numerous studies that suggest higher protein diets result in a lower BF%.

    2) Yeah, I would agree.

    3) Yep, that's called tolerance.

    4) I really couldn't comment on that since I haven't specifically researched that.

    5) Whoa wo wo. ASP is part of the problem, true. But it turns out that ASP and insulin suggested to be REALLY closely related. Fasting C3 (that correlates with ASP) correlates (positively) with fasting insulin (in Pimas, at least) -
    Mind you, we're talking about the postprandial situation. So I found this study:
    But the thing is, personally speaking, carbohydrate is a DRUG. I feel shit all the time (I have atypical depression at the moment) and then I eat pure starch/sugar. The feeling is like no other. But I could not binge on lard. I have no emotional attatchment to fat (apart from on my body - not dietary). Carbs are crazy - wait no, I think I am.
    Anyway, I was saying that people can and WILL overeat carbs beyond the point of fullness because it's drug-like (Robert Lustig goes on about this) and when carbs are combined with the mouthfeel of fat, you're f*cked, becuase it's a feeling. An insulin - C3/ ASP combo postprandially is bad. Especially when you have your arse sat on a sofa.

    I also read this study that found ASP to correlate with chylomicrons, which were secreted primarily in response to dietary fat. Can't remember where (low blood sugar).

    Cortisol and insulin work together. That's why (maybe) people with atypical depression gain tons of weight. I don't gain weight per se (though) because I lose muscle and gain fat. I think there's a stress epidemic as well as a sugar epidemic.

    As a penultimate note, if you take olanzapine (or like) you're fucked. It causes leptin resistance. The point about leptin is that there is a negative feeback loop that prevents its resistance and stuff which might disrupt that loop could be the cause of obesity. Triglcerides block leptin at the brain, and they are usually correlated with insulin. Genes come in somewhere here too (some do better on HFLC, whereas others don't).

    Correlation is NOT causation.

    I'm 15. I'm obsessed. And I want the answer.

  20. Cat
    Counting calories is stressful. LCHF doesn't do it. Lower cortisol.

    The typical brain likes ketones (look at the ketogenic diet with epileptics). Lower cortisol.

    Your GI tract and leptin love short-chain fatty acids. In LCHF you get more, and in high fibre diets you get more. Lower cortisol.

    Feed a rat a highly palatable diet ad libidum and it gets fat. Same goes for the average human. Highly palatable is subject to tolerance too, you know; it can become the norm.

    Palatability, IMO, correlates with how proccesed it is (with the exception of fruit and dairy). E.g. raw meat is repulsive and cooked meat is great. Mollasses taste like SH1T and sugar can make even dog turd taste great. Nobody eats oil alone but in cake, crisps, or chocolate, it's consumed a lot (yeah, just smell some industry-standard veg oil and nausea will inundate you - I did it during a chemistry lesson and couldn't eat for the next 2 hours).

  21. Cat
    Oh, and blood sugar fluctuations are stressful. Higher cortisol. My main reason for the HFLC.

    Did you know that there is a glucocorticoid receptor on the insulin gene thing. Chronic glucocorticoid elevation causes insulin (thus leptin) resistance. You just have to look at someone with Cushings Syndrome, and it's NOT their fault. More energy is being partitioned into fat.

  22. Cat
    You can partition more "calories" into muscle by doing weight training/ anaerobic training and eating a diet higher in protein (to a point, because protein causes postprandial cortisol levels to rise). Look at bodybuilders. They know what they're doing.

    In support of the insulin thing, there is an eating disorder called diabulimia where T1 diabetics omit their insulin shots specifically to lose weight. They know it works. You can look it up on google and find out. That's compelling.

  23. Cat
    The leptin system is more sensitive to undernutrition than overnutrition in most of the population.
  24. Keele
    Fat IS the problem. People are going on these low carb, high fat, meat loaded, green and yellow vegtable diets and not only does it lead to heart problems but a serious lack of energy and MORE fat storage. The fat you eat is the fat you wear. There are three common fuel sources, carbs, fat and simple sugars. Our bodies and our brain is built to run on carbs. People who choose a more 'paleo diet' approach are choosing to use fat and simple sugars as fuel. Plant and animal fat are stored in the adipose tissue under the skin and add weight to your frame. Carbs are stored in the liver and muscles, not adding *significant weight to your frame, and is burned as energy throughout the day. When you don't use the whole 'stock pile' it is released through the lungs and pores as energy or heat. You would have to eat over 25 cups of rice a DAY to start adding weight to your frame. The reason people gain weight when eating carbs and fats is because the body is choosing the carb fuel over the fat, so the fats stay snug in the adipose tissue. Cut the fats, up the carbs. I've lost 50 lbs and now do crossfit three times a week and olympic weight lifting on this starch and plant based diet (vegan) Dr. Mcdougall saved my mid 20's. I highly recommend anyone reading this to check out his literature and youtube channel.

Leave a reply

Reply to comment #0 by

Older posts