Insulin Resistance — Not the Whole Story

This is not good news, but it is important. Ace blogger Janet “Jenny” Ruhl of Diabetes Update reports that “[A new study proves that] the epidemic of [Type 2] diabetes we are seeing among children and people in their teens is NOT caused by overeating and failure to exercise. It’s caused by genetic damage to the mitochondria — the parts of the cell that burn glucose.”


The study by European researchers in the March 2010 issue of Diabetes Care found specific genetic damage in the muscle cells of young people with diabetes. Their muscle cells did not respond to exercise the way most people’s muscles do; the subjects’ cells expressed much less of the chemicals needed to metabolize glucose.

The exact chemistry involved is complicated and can be reviewed by reading the study’s abstract, but one thing seems clear. Young people with diabetes have genetic damage, not necessarily bad lifestyles. The same may be true of obese young people who do not have diabetes.

Janet wrote,

Genetic damage like this occurs when children have been damaged in the womb by chemical exposures to substances ranging from pharmaceutical drugs the mother takes, to the herbicide atrazine in the water their mother drank, to pesticides in their food, to PCBs in dust, and to the plastics leaching into food from cans and containers. Once you damage a gene that occurs in every cell that burns glucose, the damage is not reversible.

Remember that Type 2 diabetes has usually been considered a disease of insulin resistance (IR). The beta cells break down because they can’t keep up with increased demands caused by IR. I wrote Janet to ask about this theory.

She wrote back, “The belief that Type 2 is almost entirely caused by insulin resistance is commonly cited in the media and many doctors, but it isn’t supported by the evidence.” She quoted an international study, which found that “most of the [gene variants associated with diabetes] influence insulin secretion rather than insulin resistance.”

“Insulin resistance is not Type 2 diabetes,” she continued. “It’s important to realize that two thirds of older adults are insulin resistant, but only about 9% develop diabetes. The rest just grow more beta cells and stay insulin resistant, with mildly abnormal blood sugars that don’t progress. You really do need some borderline and/or broken genes to take that next step.” To read more of her interesting take on diabetes, see her Web site, Blood Sugar 101.

What Does This Mean?
The reason I say this is “not good news” is that there is no treatment for genetic damage. If you have this kind of damage, exercise will probably not do you as much good as we would like. You are much more likely to need insulin.

We can add these genetic damage–related causes of insulin resistance to the genetic damage–related causes of poor insulin production — a condition usually called MODY, or maturity-onset diabetes of the young. There are at least six different types of MODY, and now we may have another dozen genetic types of insulin resistance.

I don’t totally agree with Janet. The whole theory expressed in my book, that stress (especially socioeconomic stress) and physical inactivity are the main causes of Type 2, might be less true if genetic damage is more important than IR. Janet says that poor people might have more Type 2 because they are exposed to more pollution, not because they are under more stress. I think she might be generalizing from a group of younger Type 2s, who probably do have MODY (as she herself does) or other genetic defects, to include everyone with Type 2, most of whom may not.

But in any case, insulin resistance is still important. For one thing, it predisposes you to cholesterol problems and high blood pressure, as well as diabetes. It also comes along with inflammation, causing blood vessel damage.

We still want to reduce stress, increase exercise, and do the things that tend to reduce IR. But what we should NOT do is blame Type 2 on “lifestyle.” Nor should we expect dramatic improvements in diabetes based on lifestyle change in people who have this genetic damage.

It’s hard to find out if you have such damage, however. There are roughly 20 gene variants that have been connected with Type 2, and getting tested for all of them would be very expensive. Also, since there isn’t much you can do about them, it might be better just to treat how you feel and do what keeps your numbers down. One thing is certain: For docs who say to stay off insulin because it makes you fat, and fat is the problem, this research is another slap in the face. Maybe they’ll stop talking soon.

I would like to hear what you think about this. Does knowing that you may have some of these genetic defects make you feel better or worse? Do you even believe it could be true? What, if anything, do you see yourself doing with this knowledge?

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  • Calgarydiabetic

    Dear David

    Thanks for the really bad news. As a Chem Eng I always wondered what will happen to humanity with the million or so “un-natural” chemicals we have released into our environment “in our attempt at better living through chemistry”.

    I am amazed that the cancer rates have not skyrocketed but diabetes has and this in most if not all developed countries.

    This finding I think is a better explanation than Vit D deficiency. But vit D has some merit too.

    I think stress is a major factor in the development of diabetes so I think you are dead right about that one.

    Injecting insulin will make you fat which is not good but high BG will kill or severely maim you. catch 22.

    If this research is correct then curing diabetes is more difficult than in my worst nightmare.

  • Tammy

    I initially was diagnosed as Type 2 – then Type 1.5 – all of the info out there is what is stressing me out. I have nerve damage in my feet and I do everything I can for myself. I changed all of my eating habits – yes occasionally I stray -but for the majority of time I changed everything to whole grains/fresh fruits/veg etc – Got a membership to the gym and still my numbers rise. It seems I can’t get enough insulin and oral meds. There is not a lot of info out about 1.5 (or if there is I can’t find it)- so everything I read I try to take into account. Would this explain why no matter why I do I can’t seem to get things under control? Sure would make me feel like not quite the failure.

  • Ilya B

    Frankly speaking the study is complete garbage. To ascertain that gene VARIANTS(polymorphisms) present in people with Diabetes are genetically acquired is probably the most egregious stupidity witnessed since Galileo. The gene VARIANTS(polymorphisms) encountered are result of changes that occurred LATER to the original gene structure(which was intact before them) and are caused by oxidative stress under over-expressed HIF-1a(hypoxic exposure). In order to prove their point the so-called scientists should be able to compare genetic material at birth and after Diabetes diagnosis. Blame it on the genes is poor excuse for not knowing the cause and etiology of a disease and only deflects the attention.
    @Tammy You follow guidelines that TOTALLY wrong and disastrous. I challenge you online that you will get an instant control of your Diabetes in 24 to 48 hours with a shift in your diet and with the help of your gym card and I’m not kidding. That’s in case that you are NOT taking insulin at present.

  • Jenny

    Interesting article but I would still question if we really have an epidemic of children and teens with type 2. To be honest I’m more annoyed with the amount of attention children with type 2 get in the media. Type one is still by far the most common form of diabetes among children yet the media continue to act like type 2 is the bigger threat to kids. Also i’ve read very little hard evidence about actual numbers of children with type 2. Just articles that repeat cliches about a rise in children with type 2 diabetes over the last 30 years.

  • Diabetes in Peru

    Dear David,
    it´s a really interesting entry, but I cannot question the information given in it. The first reason is that your simplyfing the causes people get diabetes (type 2 mostly). Your basically saying that the only cause you can get it is because you have a genetic problem that was “awarded” to you ever since you were in your mothers womb.

    Now, modern science now a days tries to look at diferent variables which can give you a better look at the problem at hand.

    The other reason I believe you might be making a mistake is that to say that your genes are crap is going to help people stop caring for their health because lot´s of people are going to start thinking: “What am I going to do, I mean it´s not the fact that I eat 20 donuts a day, but it´s all in my genes”. It kind of gives a doomsday perspective on getting diabetes, and worst, being able to find a cure for it.

    I think, however, that this is also helpful information to have, because it can give you a different point of view from which we can also get valuable insight on the future of our problem.

    Thanx for your blog

  • Kimmie K.

    I was told 7 years ago that I may have insulin resistance. I had a dark thickened velvety patch that was found in the folds of the skin (armpit, groin and the back of the neck). I had researched this condition which is called Acanthosis Nigricans, which it can occur with endocrine diseases such as diabetes. It is common in people who have insulin resistance. When I was very young, about 8 years old, my whole neck was the color of a milk chocolate bar, and my parents thought it was due to oily skin. Since I’m older, I have asked my siblings to check for diabetes, including of having their children checked. Thank you for the blog information David!

  • Beth


    AS you know, I have been saying for many years that the increase in diabetes was too rapid to be caused only by lifestyle changes — that there MUST be environmental causes, and that plastic residues and agricultural chemicals are a good place to look. Sadly, the evidence is showing that is so.