the carbohydrates in wheat are composed of polymers (repeating chains) of the simple sugar glucose,
unlike simple carbohydrates such as sucrose, which are one or two-unit sugar structures. (Sucrose is a
two-sugar molecule, glucose + fructose.) Conventional wisdom, such as that from your dietitian or the
USDA, says we should all reduce our consumption of simple carbohydrates in the form of candy and soft
drinks, and increase our consumption of complex carbohydrates, such as the almighty synthetic wheat of
today and other problematic grains.
Of the complex carbohydrate in wheat, 75 percent is the chains of sugar we call glucose (the form of
sugar your body burns as fuel) in a form we call Amylopectin. The remaining 25 percent is in a chain of
glucose units, we call Amylose. In the human gastrointestinal tract, both Amylopectin and Amylose are
digested by the salivary and stomach enzyme amylase. Amylopectin is efficiently digested by amylase to
glucose for our fuel and or storage of fat, while Amylose is much less efficiently digested, some of it
making its way to the colon undigested. Thus, the complex carbohydrate Amylopectin is rapidly converted
to glucose and absorbed into the bloodstream and, because it is most efficiently digested, is mainly
responsible for wheat’s blood-sugar-increasing effect. The Amylose doesn't have this effect on blood
Other carbohydrate foods also contain Amylopectin, but not the same kind of Amylopectin as wheat,
which is called Amylopectin A. Amylopectin varies depending on its source. Amylopectin from legumes,
so-called amylopectin C, is the least digestible. Undigested Amylopectin makes its way to the colon,
whereupon the symbiotic bacteria happily dwelling there feast on the undigested starches and generate
gases such as nitrogen and hydrogen, making the sugars unavailable for you to digest.
Amylopectin B is the form found in bananas and potatoes and, while more digestible than bean
Amylopectin C, still resists digestion to some degree. The most digestible form of Amylopectin,
Amylopectin A, is the form found in wheat. Because it is the most digestible, it is the form that most
enthusiastically increases blood sugar. This explains why, gram for gram, wheat increases blood sugar to
a greater degree than, say, kidney beans or potato chips. The Amylopectin A of wheat products, complex
or not, might be regarded as a Super-carbohydrate, a form of highly digestible carbohydrate that is more
efficiently converted to blood sugar than nearly all other carbohydrate foods, simple or complex. This
means, insulin levels rise and pack our cells with sugar, yes even
the fat cells.
This means that not all complex carbohydrates are created
equal, with Amylopectin A-containing wheat increasing blood
sugar more than other complex carbohydrates. But the uniquely
digestible Amylopectin A of wheat also means that the complex
carbohydrate of wheat products, on a gram-for-gram basis, are
no better, and are often far worse, than even simple
carbohydrates such as sucrose.
Consider this; whole wheat bread increases blood sugar to a higher level than sucrose (table sugar).
Aside from some extra fiber, eating two slices of whole wheat bread is really little different, and often
worse, than drinking a can of sugar-sweetened coca cola or eating a sugary candy bar.
This information is not new. A 1981 University of Toronto study launched the concept of the glycemic
index, i.e., the comparative blood sugar effects of carbohydrates: the higher the blood sugar after
consuming a specific food compared to glucose, the higher the glycemic index (GI).
The original study showed that the GI of white bread was 69, while the GI of
whole grain bread was 72 and Shredded Wheat cereal was 67, while that of
sucrose (table sugar) was 59.5. Yes, the GI of whole grain bread is higher
than that of sucrose. Incidentally, the GI of a Mars bar is 68. That’s better
than whole grain bread. The GI of a Snickers bar is 41—far better than whole
grain bread as well.