Sweet Poison?

Sugar holds a special place in the dietary consciousness of many people with diabetes. When they first receive their diagnosis, many people worry that they will no longer be able to enjoy their favorite sweet treats — before being reassured, in many cases, that there is no one food they must give up. Many people, in fact — including medical professionals — subscribe to the view that in people with diabetes, sugar intake is unimportant aside from its contribution toward total carbohydrate intake.


A competing view of sugar, however, has been voiced for decades but has recently gained prominence due to the advocacy of Robert Lustig, MD, an obesity expert at the University of California, San Francisco, School of Medicine. Lustig believes that sugar is a toxin, with a unique role in the development of metabolic syndrome (the common coexistence of insulin resistance, hypertension, obesity, and abnormal blood lipid levels). In 2009, Lustig gave a lecture entitled “Sugar: The Bitter Truth,” which has since attracted more than a million views on YouTube. In the lecture, he posits that fructose — which makes up 50% of table sugar or sucrose, and a slightly higher percentage of high-fructose corn syrup — is metabolized by the liver in such a way that a toxic by-product is produced, which may be responsible for health problems that have become more common at the same time that sugar consumption has risen.

In an article published last week in The New York Times Magazine, science writer Gary Taubes examines Lustig’s case and comes mostly to agree with it — while noting that the evidence is not conclusive. Taubes notes that the last official examination of sugar by US health authorities, at the Institutes of Medicine in 2005, found potential negative effects from sugar consumption but did not set a goal for the upper limit of sugar consumption. An often-cited older government study, however, conducted by the FDA in 1986, found that sugar consumption at 40 pounds per person per year could not be significantly linked to negative effects on health. Department of Agriculture estimates at the time, however, put average sugar consumption at 75 pounds per person per year, and by the early 2000s that number had risen to 90 pounds per person per year. At roughly the same time, the obesity rate rose from 1 in 7 Americans in 1980 to 1 in 3 in the early 2000s, and the rate of diagnosed diabetes rose from less than 3% in 1980 to more than 5% in the early 2000s. Taubes also links sugar — less forcefully, based on the role of insulin in the growth of tumors — to certain forms of cancer.

Of course, these assertions have not been backed up by a large-scale, multiyear, randomized controlled study on sugar consumption — and such a study would be very difficult to conduct. Moreover, it is unclear what effect sugar would have on people who already have Type 2 diabetes even if it played a distinct role in the development of the disease. Nevertheless, Taubes’s article raises questions that are relevant to all people with diabetes.

Do you believe that sugar might have played a role in your developing diabetes? What role does sugar currently play in your diet? Do you make a distinction among sucrose, high-fructose corn syrup, and natural sugar found in fruits and vegetables? How much sugar — whether added refined sugars, or natural ones — is too much? Leave a comment below!

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  • Jane Simpson

    I have a sweet tooth that can’t resist sugary treats, for example jelly beans for Easter.
    When I was first diagnosed an internist told me that consuming sugar even if I was counting carbs
    would endanger my eyes and possibly lead to blindness.
    I believe that sugar is addictive to people with the genes for other addictions.
    I use aspartame and other sugar substitutes when adding sweeteners to food.
    How can I take charge of my addiction?

  • T.P.

    Has anyone accounted for the aging population of baby boomers? Or for the fact that baby boomers actually go to doctors? Seems to me that more diabetes would be diagnosed when way more people are not only reaching an age when diabetes has traditionally been diagnosed, AND that population is far more likely to see doctors on a regular basis than previous generations. I come from a large family of large families – some of us have diabetes, and some of us don’t. We are all about the same weight, and our diets and activity levels are all similar. However, I can look back at earlier generations and see that they probably had undiagnosed diabetes. They didn’t go to doctors unless they were quite sick, and doctors didn’t routinely screen for diabetes. They gave them antibiotics!

  • Ron Timmons

    I have no idea if sugar is toxic. I do know that after reading Michael Pollan’s book “The Omnivore’s Dilemma” (and subsequent books by him) I have avoided High Fructose Corn Syrup like the plague. This is not easy to do. It is in virtually everything. One has to read labels on every non-produce item in the grocery store to buy food without HFCS, but it can be done. I personally believe HFCS is poison. I think school children are fed a steady diet of it and this may account for their obesity and onset of diabetes at an extremely early age. It makes me ill to see teenagers walking around with liter-sized soft drinks which are 100% High Fructose Corn Syrup. I have read articles, some of which were on this site, stating that ingesting HFCS not only does not reduce hunger, but for some metabolic reasons I’m not qualified to discuss, actually increases hunger. You can bet your bottom dollar that these kids are walking around with blood sugar levels of over 300 most of the day. I have become something of a zealot on this subject, but if you are reading this and believe anecdotal evidence, let me say I’ve been diabetic for 37 years (and probably before that), once weighed 230 pounds (now 172)and will not eat anything that has High Fructose Corn Syrup in it. My hbA1c is 6.0, I use isulin and Metformin (dropped Avandia last year) and am in pretty good health for age 77. AVOID HFCS!
    Ron Timmons

  • DrBC

    I have watched Dr. Robert Lustig’s lecture on UTube. His arguments are very forceful and his conclusions surely seem to have scientific basis.

    Circumstantially also his conclusions are well supported. Our modern life style and changed pattern of food containing much higher calories and most of them coming from plain sugars and fructose also makes us draw the same conclusion that increased incidences of diabetes, obesity, metabolic syndrome, cardiovascular diseases and cancers are all interconnected. It makes us look in the direction of sugar, since when low fat, low cholesterol craze has taken root particularly the post WWII time frame. And after late 1970s the fructose seem to have made that impact worse in the shape of exponential rise in incidences of these diseases.

    This certainly warrants urgent attention of all regulatory and disease control organizations, both government and private to gear up their research onto these. Hopefully we will then b3 able to prevent many of these serious conditions and save a lot of miseries in the future.

  • Limmy Claxton

    I’ve been living with type2 diabetes since 1999. Through diet and exercise I now am medication free. I only use honey and don’t buy sugar or artificial sugars full of manmade chemicals. I allow myself a brownie every now and then and eat alot of fruits and citrus products to provide natural sugars that my body doesn’t have to try and figure out what to do with like it does from table sugar or high fructose products. This new approach to diet and exercise has helped me lose 30 pounds and get my sugar under control.

    Since I stopped using sugar my energy level has returned to normal and my body feels clean and balanced without all the toxic mess sugar causes.

  • Eva Walker

    I have had Type 1 for 48 years and a lot has changed with treating diabetes in all theses years.I can remember having to boil my syringe every morning before preparing my shot.There was no blood testing monitors etc.I was told to take corn syrup when I had low blood sugar.With Monsanto I finally switched to organic unpasturized honey and only eat home grown foods made from scratch.I finally got an insulin pump and waiting for an instructor to show up and teach me how to use it.

  • Eva Walker

    This comment has to do with avoiding sugar.Aspertame is poison.One of the side effects is increased hunger.I know because I have had that myself.Another is sezures.I let my son use it to prevent tooth decay who started getting petite maul sezures.It makes me laugh when I see people come out of McDonalds with a big Mac and a large container of diet soda.

  • pam

    Recently diagnosed with type 2. Just learning how to check my blood surgar numbers. I stopped all sugar in the begining. No sugar in my coffee. No white breads. No patry at work and so on. On day three I and almost died, because my surgar dropped so low.
    I have never been a fan of Aspertame it is BAD. We have to have sugar to live . I am learning how to choose whole foods when possible.

  • Barbara Smith

    My grandfather raised sorghum cane for years (his entire adult life) and enjoyed things made with it and he never developed diabetes but he rarely ever used the refined sugar that we use now nor did he ever consume high fructose products. He always felt that nature produced what we needed and that if we messed with it we would become ill. I have developed type 2 as an adult but I have used refined sugar. We compared amoung all of the cousins recently and the ones that used refined sugar products, especially high fructose, have a much higher tendency to develop type 2 when compared with the ones that stayed on the farms and used only a truly natural source. It could be the minerals that are in sorghum that help protect you or the fact that you use a lot less sorghum products than refined because the taste is much stronger. Also there is a huge lifestyle difference – hard physical work on the farms vs city life and office jobs. I believe that both the type of sugar and physical activity are the difference between the results so yes, refined sugar and or high fructose is not that good for you and could cause toxins to build up and damage the syste.

  • mike

    I only use cane sugar or honey some molassess.I feel that the spead of diebets is from hfcs I try to avoid products with that

  • Donna Pease

    I have type 2 diabetes and have just used diet and exercise for many years to handle it. I am just getting over Pneumonia and spent 5 days in the hospital. While there they gave me insulin, now I am home and not on anything but am having trouble keeping my numbers down, because I can’t exercise.
    As for sugar, If you can stay completely off sugar and white flour etc.for one week you will no longer crave sweets. after one week, you can use fruit sparingly, especially berries. Start counting fiber and be sure to get at least 12 to 15 grams at every meal. This will help your diabetes more than anything

  • Rosemary Poter

    I’m not a super sweet eater. Usually I would rather have a Kosher pickle than candy. But, I believe my Type II was helped along by the sugar produced by regular carbs. Our flour, for bread, pasta (I’m part Italian and didn’t think I could live without pasta in my life)crackers and other flour based foods is so full of gluten that it is much more apt to make sugar and pack on the pounds of fat. The other problem is artificial sugars in our food which create cravings beyond what regular sugar might. Let’s not forget the ‘diet’ sodas. I have had to eliminate most carbs from my diet, except for organic veggies and have not only lost weight, but have more energy and virtually no cravings for processed carb foods.

  • Joye

    I am diabetic and allergic to all well known/well used artificial sweeteners, including Splenda & agava. However I recently found two I can use: Diabeti Sweet from Diabetic products and Xylitol from Emerald Forest. The downside is that they cost over $8 a pound! As a result, I usually just use sugar and count the carbs. I may try using one of the “safe” sweeteners for making deserts, but I haven’t had time to figure amounts yet. Even though they SAY they work like sugar in recipes, I’ve found that all I’ve tried end up a lot sweeter, of poor quality, or with a strange after taste (as well as setting off a reaction after a couple bites.)

    Has anyone else used either product I’ve found “safe” in baked or cooked recipes? if so, what were the results?

  • Lynne Nelson

    I believe that consuming processed foods that contained high fructose corn syrup contributed to my diabetes as the condition was diagnosed after several years of using frozen diet meals from various companies. What I did notice was that high fructose corn syrup was listed on the label on many of the foods whether sweets or regular meals. At the time, I had no reason to question the latter as an ingredient.
    However, currently I do not consume food with corn syrup of any kind nor do I use any artificial substitutes for sugar. I don’t believe nature intended for us to eat 40 pounds of sugar each year. I use Stevia to sweeten my yogurt and only eat sugared desserts a few times each year.
    Persons with diabetes by definition are unable to process sugar without detriment to the pancreas, so it’s better to give it up than risk progression of the disease, in my opinion.


    I find that I do not like sweetners and I rarely drink soda. After 25 years as a type two diabetic I find cane suger reacts well for me. Now I’m not saying I eat lots of it but I do use it on occasion with no rise in fbs. I had some surgery where my pancries was brused and I don’t produce insuin . I have a A1C of 6.5 and feel well

  • Jay

    I was underweight as a child and also into my twenties. In my teens and beyond I consumed more candy each year. My wife was never overweight but became a diabetic at age 29. first 13 years on pills, then insulin, then kidney failure and death at age 57. During those years, I was careless, ate excessive candy and was 25 pounds overweight by age 57. Also was a borderline diabetic. At 65 I was type 2, on pills and a low sugar diet. Slowly my weight went down 25 pounds to normal. I blame the candy for my weight and diabetes. At 78, I now avoid real sugar and fruit juice and bread. Ice cream is my addiction, but stopped buying it this winter. Really helped my HgA1C test.

  • still too fat

    Sugar is sugar. It makes no difference if it comes from corn, cane, beets, milk, fruit, or bees.

  • Becky

    I think the key is all things in moderation. I do not think sugar had anything to do with my diabetes. I have never been a big sweet eater. When I was a kid, too much sugar made me feel sick to my stomach so I learned to keep it at a minimum. Even the sugar in juice and fruit was too much if I over-indulged, so I learned to choose carefully. I have never been overweight, even when pregnant, yet had gestational diabetes. I was diagnosed with type 2 in 2005, which has now been changed to type 1. The doctor actually doesn’t know what kind of diabetes I have. But, I am sure it doesn’t relate to sugar intake.

  • Richard

    My Diabetus started when I started the drug Seroquel.

  • aquariusrmw

    My diabetes, I believe, was brought on by stress(had relocated, no job, car stolen) and eating sweets. I was making a yellow cake with chocolate icing, every week and eating the entire cake. I was drinking a lot of Kool-Aid, and not exercising. Being that i am working, (still not exercising-but have a physical job), and able to do things, i have kept my diabetes under control since 2008. My sugar range when i got sick in 2007, was in the 600-700 range. I was off of insulin within a year, and have had my metformin lowered. Still eat my sweets, though.

  • Duffy

    I have a stressful position and for years I was a Pepsi “addict”, as well as a sweets lover. I have no doubt that these issues heavily contributed to my Type 2. Now I drink water, un~sweetned tea and (fat free) milk. Have pretty much lost my desire for most sweets.

  • Derek

    I am entirely convinced that Fructose directly causes Fatty Liver when consumed quickly and in large quantities on a regular basis. This fatty liver in turn causes insulin resistance. Insulin resistance causes many things, including most notably an increase in appetite (via a couple of mechanisms, such as high triglycerides blocking leptin signaling) and a promotion of sedentary behavior. This ultimately leads to all the problems of metabolic syndrome: obesity, type II diabetes, cardiovascular disease, etc.

    I have cut all sugar from my diet, and heavily restricted all other carbohydrate, and the change in my life has been amazing. I’m no longer hungry 24/7, my body isn’t trying to make me be sedentary to preserve energy, my mood has stabilized and elevated, I’ve lost 125 pounds (plenty more to go), my HDL cholesterol is way up, my triglycerides are way down, my LDL is large fluffy (ask for a VAP test, not all LDL is bad!), and I have no need for any medication.

    Also, I should note that saturated fat doesn’t cause heart disease. Saturated fat increases LDL, but the good LDL, the large fluffy LDL, not the bad, small dense LDL… which is caused by? You guessed it, sugar. So enjoy your bacon and steak!

    Taubes and Lustig are completely right on!