Could Fructose Cause Diabetes?

Lumps of Diabetes

Cubes of Diabetes?

A Pharm.D (Dr of Pharmacology) and a pair of MD’s surveyed much of the available scientific literature—both animal and human studies—and concluded that fructose is a major culprit in the rise of type 2 diabetes and prediabetes. Fructose does its damage by increasing insulin resistance. ScienceDaily has the details.

Be aware that their conclusion is certainly not universally accepted. I read “Pathogenesis of type 2 diabetes mellitus” at a few months ago and saw no mention of fructose. Under dietary factors, they mainly talked about obesity and how that increases insulin resistance, leading to elevated blood sugars, while the reverse happens with weight loss. I haven’t looked at all the research so I have no definite opinion yet on the fructose-diabetes theory; I’m skeptical.

Fructose is a type of simple sugar. Common dietary sources of fructose are fruits, table sugar (aka sucrose, a 50:50 combination of glucose and fructose molecules), and high-fructose corn syrup (which is usually 42 or 55% fructose).

Damaging effects, if any, of fructose in these fruits may be mitigated by the fiber

Damaging effects, if any, of fructose in these fruits may be mitigated by the fiber

A few quotes from ScienceDaily:

“At current levels, added-sugar consumption, and added-fructose consumption in particular, are fueling a worsening epidemic of type 2 diabetes,” said lead author James J. DiNicolantonio, PharmD, a cardiovascular research scientist at Saint Luke’s Mid America Heart Institute, Kansas City, MO. “Approximately 40% of U.S. adults already have some degree of insulin resistance with projections that nearly the same percentage will eventually develop frank diabetes.”

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While fructose is found naturally in some whole foods like fruits and vegetables, consuming these foods poses no problem for human health. Indeed, consuming fruits and vegetables is likely protective against diabetes and broader cardiometabolic dysfunction, explained DiNicolantonio and colleagues. The authors propose that dietary guidelines should be modified to encourage individuals to replace processed foods, laden with added sugars and fructose, with whole foods like fruits and vegetables. “Most existing guidelines fall short of this mark at the potential cost of worsening rates of diabetes and related cardiovascular and other consequences,” they wrote.

If you’re eating a typical Western or American diet, you’ll reduce your fructose consumption by adopting the Paleobetic DietMediterranean diet, or Low-Carb Mediterranean Diet.


Steve Parker, M.D.

3 responses to “Could Fructose Cause Diabetes?

  1. I’m also sceptical. Diabetes is a syndrome and far too complex to be blamed on a single cause such as fructose.

    We always seem to be looking for someone or something to blame for our T2 Diabetes instead of using our common sense about the amount of food we eat.

    I have a genetic *predisposition* to T2 so it’s my responsibility to make sure that I eat the foods that don’t elevate my blood glucose.

    T2 may have a variety of causes ranging from lack of exercise through fructose through certain chemicals in plastic alleged to cause insulin resistance/diabetes.

    What if it’s caused by a “perfect storm” of factors both known and unknown?

  2. Raise the level of fructose in your diet to keep your liver full of glycogen all the time. I think you’ll see the effect.

  3. I wanted to make a general comment that is based on my experience doing computer performance tuning. What happens is that the system is slow because of some bottleneck somewhere, and you fix the bottleneck, and then you see the computer is still slow because of some other bottleneck that was behind the first bottleneck and therefore invisible until you fixed the first bottleneck–the bottlenecks weren’t additive–the second one only appeared because you fixed the first one.
    So, suppose you are hyperinsulinemic from too many calories, and you become diabetic. You are not going to see any influence from fructose. Only when you cut the calories so that body does not think it is being overfed will any fructose effects occur.
    This is why most general nutrition advice fails to accomplish anything. The biggest bottleneck hides all the myriad other problems which only manifest when the biggest problem is solved, and correct nutrition information gets a bad rap as ineffectual as a medical treatment because the practitioners or self-treating patients do not carry through to solve all the nutritional problems.