How Sugar Makes You Fat

Look at how many grams of sugar are in what you’re eating (on the nutritional label). Now divide that number by 4. That’s how many teaspoons of pure sugar you’re consuming. Kinda scary, huh? Sugar makes you fat and fatfree food isn’t really free of fat. I’ve said it before in multiple articles, but occasionally, I’ve had someone lean over my desk and say “How in the heck does sugar make you fat if there’s no fat in it?”. This article will answer that puzzler, and provide you with some helpful suggestions to achieve not only weight loss success, but improved body health.

First, let’s make some qualifications. Sugar isn’t inherently evil. Your body uses sugar to survive, and burns sugar to provide you with the energy necessary for life. Many truly healthy foods are actually broken down to sugar in the body – through the conversion of long and complex sugars called polysaccharides into short and simple sugars called monosaccharides, such as glucose. In additions to the breakdown products of fat and protein, glucose is a great energy source for your body.

However, there are two ways that sugar can sabotage your body and cause fat storage. Excess glucose is the first problem, and it involves a very simple concept. Anytime you have filled your body with more fuel than it actually needs (and this is very easy to do when eating foods with high sugar content), your liver’s sugar storage capacity is exceeded. When the liver is maximally full, the excess sugar is converted by the liver into fatty acids (that’s right – fat!) and returned to the bloodstream, where is taken throughout your body and stored (that’s right – as fat!) wherever you tend to store adipose fat cells, including, but not limited to, the popular regions of the stomach, hips, butt, and breasts.

As an unfortunate bonus, once these regions are full of adipose tissue, the fatty acids begin to spill over into your organs, like the heart, liver, and kidneys. This reduces organ ability, raises blood pressure, decreases metabolism, and weakens the immune system.

Not good!

Excess insulin is the second problem. Insulin is a major hormone in the body, and is released in high levels anytime you ingest what would be considered a “simple” carbohydrate, which would include, but not be limited to: fruit juice, white bread, most “wheat” bread (basically white bread with a little extra fiber), white rice, baked white potato, bagels, croissants, pretzels, graham crackers, vanilla wafers, waffles, corn chips, cornflakes, cake, jelly beans, sugary drinks, Gatorade, beer, and anything that has high fructose corn syrup on the nutritional label. Two actions occur when the insulin levels are spiked. First, the body’s fat burning process is shut down so that the sugar that has just been ingested can be immediately used for energy. Then, insulin takes all that sugar and puts it into your muscles. Well, not quite! Actually, most of us, except those random Ironman triathletes and 8000- calories-per-day exercisers, walk around with fairly full energy stores in the muscles. As soon as the muscles energy stores are full, the excess sugars are converted to fat and, just like the fatty acids released from the liver, stored as adipose tissue on our waistline.

But that’s not all. After the blood sugar has been reduced by going into the muscles or being converted to fat in the liver, the feedback mechanism that tells the body to stop producing insulin is slightly delayed, so blood sugar levels fall even lower, below normal measurements. This causes 1) an immediate increase in appetite, which is usually remedied by eating more food; 2) the production of a stress hormone called cortisol. Cortisol triggers the release of stored sugar from the liver to bring blood sugar levels back up, which, combined with the meal you eat from your appetite increase, begins the entire “fat storage, metabolic decrease” process over again.

This process of destabilizing blood sugar levels and sending your body on a roller coaster ride can occur throughout an entire day, week, or month. The excessive cortisol that accumulates in the body eventually distresses your hormonal system and results in other problems, including a further decrease in metabolism, obesity, depression, allergies, immune weakness, chronic fatigue syndrome and other serious side effects.

So what kind of carbohydrates can you eat to avoid de-stabilizing blood sugar levels, constantly sabotaging your weight loss, and spending hundreds of thousands of dollars in health care as you get older? Here is a list of carbohydrates do not trigger such a strong insulin response and instead provide long-term, stabilized energy: apples, oranges, pears, plums, grapes, bananas (not overly ripened), grapefruit, oatmeal, brown rice, whole wheat spaghetti and egg fettuccine, whole-wheat pasta, bran cereal, barley, bulgur, basmati, Kashi and other whole grains, beans, peas (especially chick and black-eyed), lentils, whole corn, sweet potatoes, yams, milk, yogurt (preferably low-fat or fat-free) and soy. Stay away from processed and packaged foods as much as possible, because they are highly likely to include artificial sweeteners (which basically have a similar effect as sugar), as well as simple and refined sugars. Keep your eye out for ingredients that include sucrose, maltose, dextrose, fructose, galactose, glucose, arabinose, ribose, xylose, deoxyribose, lactose, and other fake names for sugars. Even “healthy” juice and many health food products will need to be avoided if they contain high levels of sugar.

If you need more help with your diet, just let me know. Feel free to e-mail [email protected], and I’ll give you some suggestions on how a personal trainer can help you with your nutrition. My book, Shape21, includes 21 days of nutritional intake that completely stabilizes blood sugar levels, which, when combined with the perfect exercise program that I’ve detailed in the book, leaves you with a lean, athletic body. You can check it out at my website,, or at a gym near you.

If you’d like my FREE newsletter and weekly audio podcast, simply visit For a more personalized online fitness coaching, fat loss, human performance or nutrition consulting, you can also visit

Until then, train smart!

Ben Greenfield

38 Responses to “How Sugar Makes You Fat”

  1. andrea hansen July 27, 2016 at 8:28 pm #

    ok, so i am onboard with sugar makes you fat… i try to eat for fat loss, meaning good proteins and fats and veggies (non starchy) for most of the day, if not all… if I’m going to have carbs i have them at night… the

    other night i had some full fat yogurt from grass fed cows, that had 11 grams of sugar, none added, and also had some nuts and cinnamonon top and my BF said i shouldn’t eat that sugar before bed and that it would turn to fat. i was like, umm, no it won’t. but then didn’t have the best way to explain myself … also i do cross fit and interval 20 min runs….. also i was surprise in the above article that u suggested low or non fat yogurt…

    so i guess the big question is where does the sugar go if having it at night for an active woman, thanks ben 🙂

  2. Patrick Mullin April 21, 2016 at 8:20 pm #

    Great article! I used this to further explain the effects of sugar to a client and I feel it went hand in hand with my lectures for my Pn1 certification! Thanks for sharing it!

  3. Sheila April 10, 2016 at 7:35 am #

    This article explains my problem. I watch my calories and do full body workouts. But my hips, arms etc.. are holding onto fat. I eat sugar. Too much of it. I try to eat nutrient dense food but I also like sugar and wine. I have been very frustrated with an extra 7lbs I have gained this year. I have been blaming my age but am now quite convinced it’s sugar. The hard part is giving it up…… Thank you(I think ):) for the informative, straight forward and easy to understand article.

  4. Tom March 25, 2016 at 6:16 am #

    Hi Ben,

    Great article but i would just like to add that; sucrose, maltose, dextrose, fructose, galactose, glucose, arabinose, ribose, xylose, deoxyribose and lactose are not fake names for sugars. Sucrose being a disacceride, composed of 2 glucose and fructose being similar to glucose but less calorific. Deoxyribose is dna (deoxyribose nucleic acid) and lactose and galactose are not very calorific sugars either and are only found in dairy products.

    • Michiel March 9, 2017 at 8:10 am #

      I guess he meant dextrose, not deoxyribose.

  5. J February 20, 2016 at 5:14 am #

    There is so much bro science in this article it’s disgusting. Anything to sell a product.

  6. Julie devyea February 8, 2016 at 11:31 am #

    I understand what you are telling me however, I thought low fat or fat free yogurt is full of sugar substitutes because it needs flavour after the fat has been removed.

  7. Lauren November 23, 2015 at 2:05 am #

    Do you recommend I eat sugar free food instead of fat free or both? I'm trying to lose weight, and it sounds like it says in your article that sugar is technically fattening. Would it be better to eat sugar free or fat free?

    Do you have any other tips for losing weight? I'm 15 years old and am 135 pounds. I'm trying to get down to 130 pounds, but the scale won't budge if you know what I mean 🙂



    • Ben Greenfield December 21, 2015 at 8:44 pm #

      I have a tonne of stuff on weight loss. If you google Ben Greenfield + Fat Loss you'll get a bunch of stuff I've written

  8. wakeupnaija November 18, 2015 at 4:48 pm #

    Tnkz. Really helpful

  9. Ahmed November 18, 2015 at 6:20 am #

    Hello dear

    Thanks for the great article I really had no idea how sugar makes you get fat

    And btw am 185cm tall my weight is 129kg ive lost about 4-5 kgs in 3 weeks but i didn't make my tea sugar free… anyway I wanted to ask , I have been drinking orange juice that says *sugar-free* on the bottle its even have a *diet* motto on it

    And it is kinda sweet i was wondering if that is bad or not…

    Resopnd please I've ordered a set of bottles not long ago and there's 5 bottles left waiting your response XD

  10. Cara November 13, 2015 at 8:07 am #

    Yes! You turned on another light bulb in my head…lol! I finally get this! Another issue I'd like to bring up is the high protein,low carb diet and why it's advocated. Well, first of all carb and fats are the body's primary fuel source. When you eat low carb and low sugar you deplete what the body needs to burn and it starts to use the stored carbs and fat!! Thats why the Atkins got popular which I don't advocate (carbs are good to). The whole idea really is moderation and very rarey cookies, heavy breads,sauces, processed food. Most processed food is similar to drugs, ya just have to stay away from it,at least for me!!!

  11. Dan October 6, 2015 at 4:14 am #

    I was told by my doctor that I have cirrhosis of the liver but I do not drink he said it is the fatty acids that has bill up around my liver how I get rid this fatty acid and if I get rid of this fatty acid will it help my liver.

    • Ben Greenfield January 15, 2016 at 1:37 am #

      I'm not a doctor and anything I say should not be taken as medical advice, but if you wanted to talk through this it would be better over a consult. If you want to book one go to and choose 20 or 60 mins and we'll get you scheduled.

  12. Blythe September 5, 2015 at 9:07 am #

    Thank you so much this post! Glad I found it. Another question: In the body do sugar-free choices breakdown in the same way. Can the body differentiate between the refined and sugar free?

    • Ben Greenfield January 15, 2016 at 5:24 pm #

      The body can indeed tell the difference. However, many sugar-free sources that are artificial, which include most everything other than Stevia, can cause some other issues such as killing good bacteria as well as Neural toxicity.

      • John Luc Seligman December 8, 2016 at 2:44 am #

        Just keep it simple. NO refined sugar. NO meat dairy egg fish process liquid oils! ONLY ‘WHOLE FOOD PLANT BASED LIFE STYLE’. FRUIT VEG ROOTS GRAINS NUTS. LOTS OT WATER. SUPPLENT B12 + D3. DO THE

  13. David Smith August 11, 2015 at 5:04 pm #

    So if sugar makes one fat, what does MEAT, SALT, DAIRY and the so called VEGETABLE OIL does to your body? What i think I take from this article is, if I go to a restaurant and order a burger with the french fries and a pop. You are saying that it is the pop that makes me fat?

    • jo February 11, 2016 at 2:41 am #


    • Chris Love July 10, 2016 at 5:38 am #

      The bun, sugar in the condiments, simple carbs in the fries and yes the massive amounts of sugar in the soda make you fatter.

    • abubakr ahmad October 28, 2016 at 5:13 am #

      meat is protein and makes muscles strong and healthy, salt keeps insulin levels stable (if you eat the right amount), dairy makes bones strong and healthy and vegetable oil, fats, oils have lipids in them and help with major brain development until the age of 25.

  14. Adi August 1, 2015 at 2:01 pm #

    Hey! Excellent article. I just had some questions that I've always been wondering.

    How do cheat days fit into this? Are we putting on fat when we eat a cheat meal or have a cheat day?

    When people overeat and become fat, where is the line drawn? For instance, how many days can one go before that excess sugar becomes visible fat? And lastly, when we do exercise, do those fat cells decrease in size?

    • Ben Greenfield January 15, 2016 at 5:24 pm #

      This would be a really great question for us to cover in the podcast – can you call it in at


  15. Charlotte Hawk May 5, 2015 at 4:32 pm #

    It all makes sense now. Thanks to this post! I was really contemplating why sugar has a great impact to gaining weight and increasing health risk. I have watched the episode of Dr. Oz's show and he compared two different sizes/structures of fat, the ideal size and overexpanded fat size. You will notice there that there is a big difference of two. And too much intake of sugar is one of the greatest culprit why our body fat expanded. No wonder that I have this bulge waistline, I love sweets and I do not find time to exercise. Another episode I have shown, when he mentioned that taking forskolin supplement (read futher:… able to realease fatty acids from adipose tissue which is very essential in our body which increase the thermogenesis and resulting to losing body fat.

    • Apk June 14, 2016 at 1:04 am #

      Avoid Dextrose and Glucose ? Fake names for sugar ? Dextrose/Glucose are the same thing ! And are not fake names at all, Glucose is highly metabolic and not like Fructose ! It is used by diabetics as it doesnt get stored in the liver, it goes straight to the muscles ! You put all sugar in the bad box but you negate to mention the difference.


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