Sugar Can Cause Insulin Resistance & Diabetes by Joan Kent, PhD

Sugar Can Cause Insulin Resistance & Diabetes
By Joan Kent, PhD

Type 2 diabetes is epidemic in this country, and typically begins with insulin resistance.

We usually read or hear that insulin resistance is a result of overweight/obesity. This is not always the case – the reverse can be true. Insulin resistance may actually cause overweight.

But no matter which comes first – insulin resistance or overweight – the metabolic consequences are exactly the same.

This post is on the role that sugar and fructose in our diets can play in causing insulin resistance. Insulin resistance, and eventually diabetes, may result from changes in insulin receptors – their numbers and their sensitivity.

Glycemic Index

A high-carbohydrate diet can lead to insulin resistance, particularly if the carbs are high on the glycemic index (GI). High-glycemic carbs are quickly absorbed and trigger a high insulin response. Sugar is a prime example of a high-GI carb.

Those high levels of insulin can in turn lead to a diminished response by the body to insulin, due to something known as “down-regulation”. Down-regulation is a term originally borrowed from brain chemistry research. It occurs when there’s too much of a substance. The body down-regulates to maintain homeostasis, its “status quo.”

With insulin, down-regulation refers to a reduced number of insulin receptors and reduced sensitivity of the remaining receptors.

As a result, whatever insulin is available no longer works as well as it did before. That’s insulin resistance.

How Insulin Resistance Causes Disease

The pancreas must then produce much more insulin to get the job done. That’s what leads to the various diseases that are linked with insulin resistance, including diabetes, high blood pressure, high cholesterol and high triglycerides. All of those may in turn lead to heart disease.

Other diseases linked with insulin resistance are breast cancer, other cancers, polycystic ovary syndrome, polycystic kidney disease, and more.

Down-regulation is more likely for someone who is carbohydrate sensitive. Carb sensitivity, often genetic, is an exaggerated insulin response to sucrose or other carbs. That extra-high insulin release can easily down-regulate the insulin receptors. Down-regulation of insulin receptors occurs fairly rapidly.

So eating sugar – especially lots of sugar, as might occur with sugar addiction – can cause insulin resistance. And its many consequences.

What About Fructose?

It’s a well-known scientific fact that fructose – the sugar in fruit, fruit juice, agave, honey – triggers insulin resistance.

There’s an odd adaptation here. Yes, the original research was done on animals, but studies on human subjects have shown similar results – although athletic training can modify the results somewhat.

Fructose has been shown to change muscle fibers from type 1 to type 2b. Type 1 fibers are high-endurance fibers that respond well to insulin. Type 2b fibers are better for explosive power but less responsive to insulin.

What’s the Bottom Line?

Fructose may cause insulin resistance in this odd way. Fructose is half of the sucrose molecule. Sucrose is granulated table sugar that everyone knows is junk.

We might then say that sucrose is capable of causing insulin resistance through both mechanisms: down-regulation of insulin receptors and modified muscle fiber type due to the fructose in it.

This is even truer if sucrose is eaten in large quantities – for example, by someone who’s addicted to it.

All scientific research seems to confirm that the fructose in sucrose is what makes sucrose the junk that it is. Fructose itself is junk.

Healthful Recommendations?

Skip the sugar whenever possible. Definitely skip processed fructose or concentrated fruit juice used as a sweetener. Get your wholesome nutrients primarily from vegetables. Eat fruit, but in limited quantities (1-2 servings per day).

This may not be what you’ll hear most places, but it may work far better than what you will hear elsewhere.

Fortunately, insulin resistance and many of its health consequences are reversible. If you’d like help reversing them, that’s what I do. Just visit www.LastResortNutrition.com and request your free Eating Empowerment Session. Find out how a few tweaks can improve your health and make you feel better than you did in your 20s!