The Myth of the Glycemic Index and Its Child: "Good Carbs-Bad Carbs"

The Glycemic Index Has Befuddled Millions

The Glycemic Index (GI), first described by University of Toronto researchers, has been the basis of many major diet and weight control programs of the last decade, the South Beach Diet as an example.

It's clear that the researchers themselves and the endless legions of doctors and pseudo-expert writers (comprised of journalists, fitness trainers, and other pundits) never really read the results of the published paper that first appeared in the American Journal of Clinical Nutrition in 1981.

the test of different carbohydrate foods was made using 50-gram portions of the investigated food, a fact that's critical to know in our analysis
the authors talked about the "great" differences in blood glucose responses existing between different foods
they were right that there were differences, but they weren't great

Even Though There Are Different Rates of Glucose Rise, This Has No Physiological Significance

So, if one food causes glucose to rise to a level of 200 milligrams per volume of blood and another only goes to 175, what does this mean?

The answer is: Nothing.

Here's what happens:

blood glucose affects our metabolism in two main ways
1) it affects the release and burning of stored fat and, 2) it affects fat storage
these are the key issues we must understand
as glucose rises, we stop releasing and burning fat from the fat cell
and we convert the glucose to body fat!

The Glycemic Index is of no value since the blood glucose levels for even the lowest GI foods are already high enough to shut down fat release.

The carbs dictate the blood glucose level. It turns out that even the lowest GI carbs increase blood glucose enough to shut down fat release and maximize the conversion of carbs to fat in the fat cells! Is that what you want? If so, eat on the Glycemic Index.

This is where they've all gone wrong. It takes very little glucose to shut down fat burning and to store carbs as fat.

Fiber in Whole Grain Foods is a Big Part of the Glycemic Index Propaganda

One of the early thoughts (still strongly held today) is that fiber slows the digestion and release of glucose into the blood:

to reiterate my point above, the rate of rise of glucose into the blood means nothing; it affects nothing
Why? Glucose conversion to body fat and the inhibition of fat release from fat cells occurs at blood glucose levels well below the blood glucose level of the lowest glycemic index foods
therefore, foods with higher GIs do not change fat release and the rate of glucose-to-fat conversion more so than lower GI foods
fat release and carb-storage-to-fat is already maxed out by the lowest GI foods

Let's see what the first research paper said about fiber:

"Surprisingly, no significant relationship was seen between glycemic index and dietary fiber"
"Furthermore, it does not appear that dietary fiber, either quantitatively or qualitatively, played an important role in the differences observed in the potato test meal"

Fiber, even though it does not affect blood glucose, is the mantra of the South Beach Diet and all the other glycemic index diets. So much for the dietary fiber "belief" system. Guys, I'm not making this stuff up. On this site and in my books, we deal with Facts.

The Glycemic Index Mantra Discusses the Idea of "Spikes" in Blood Sugar and Insulin

Discounting some carbs because they did not spike sugar is the basis basis of the Net Carb Scam.

Spikes were the key argument supporting the notion of "Good Carbs" and "Bad Carbs," leading to the idea of Net Carbs.

Net Carbs was used by the food companies to sell carbohydrate foods to unsuspecting dieters
spikes mean nothing as I pointed out above
a carb is a carb is a carb, it all digests to glucose and it's the daily TOTAL exposure to glucose that matters, not different rates of rise
insulin was never a part of the Glycemic Index
fructose (fruit sugar) messes everything up because it really converts rapidly to fat even though its GI is only 23, way lower than glucose

Glycemic Index: Tests 50-Gram Portions of Food

That's the Test for the GI of a Food

The Gi is not a test of consuming multiple foods at the same time, or even meals. You can't just add up the different GIs in a menu and arrive at the meal's GI as many are doing. It's not valid, it's all made up.

All glucose molecules are the same and they all must be disposed of by the end of the day.

More Gobbledygook: The Development of Glycemic Load

Glycation cross-linking to tissue proteins glues all your tissues together such as skin.

Glycemic Load was developed by Dr. Walter Willet, the Harvard epidemiologist and card carrying member of the low-fat Establishment.

He agrees that the total amount of carbohydrate consumed is important. He calculates Glycemic Load, a measure of total carbs consumed multiplied by the carb's GI.

Of course, since the GI is meaningless, multiplying zero by another number is still zero.

Now, for the final nail in the coffin: GI proponents have tried to get the GI recognized for more than 25 years by the American Diabetes Association to help diabetics control their sugar levels.

The Glycemic Index did not help diabetics control blood sugar and the ADA rejected it and refused to make it a part of a diabetes control program. This really irritated the Toronto doctors but, again, facts are facts, and real science will always trump beliefs, if you allow it.

There are many other details about why you shouldn't use the Glycemic Index to manage your weight or health. I detail all of this in my book, Net Carb Scam and the Hazards of Carbohydrates. I cover GI on pages 124-163, a thorough analysis based on a detailed scrutiny of the scientific literature since the introduction of the GI in 1981.

The glycemic index has many supporters who have no idea of the false science behind the flawed theory. My Net Carb Scam book outlines all of it.