High-Fiber Cereal May Ward Off Diabetes
Eating a Fiber-Rich Breakfast Cereal May Lower Insulin Levels in Those at Risk
June 18, 2004 -- Eating a bowlful of high-fiber cereal may help
prevent type 2 diabetes and other health problems in people at risk for
developing the disease.
A new study showed eating a high-fiber cereal lowered insulin
production and reduced blood glucose levels in men with elevated insulin
levels, a condition known as hyperinsulinemia.
People with hyperinsulinemia are in danger of developing type 2
diabetes because the cells in their bodies are resistant to the effects of
insulin and cannot process glucose (sugar) properly. This causes the pancreas
to produce more insulin in order to compensate. High insulin levels and insulin
resistance have also been associated with an increased risk of heart
By lowering the rise in insulin and sugar levels that normally
follows eating a meal high in carbohydrates, researchers say people at risk for
developing diabetes may be able to ward off the disease and its complications.
Other research has shown that exercise and the diabetes medication Glucophage
are also effective at preventing diabetes in these people.
High-Fiber Cereal May Help Lower Insulin Levels
In the study, which appears in the June issue of Diabetes
Care, researchers compared the effects of eating a high- or low-fiber
ready-to-eat breakfast cereal in 77 men without diabetes. Forty-two of the men
had elevated insulin levels.
The men in the high-fiber cereal group ate 1.3 cups of cereal
-- Fiber One from General Mills -- which provided nearly 36 grams of fiber. The
low-fiber cereal group ate Country Corn Flakes from General Mills which had
less than 1 gram of fiber in the 1-cup serving size.
The men with hyperinsulinemia were significantly heavier and
had larger waistlines as well as lower HDL "good" cholesterol levels
than the others. Being overweight is one of the biggest risk factors for
diabetes, and HDL cholesterol is often low in people at risk for diabetes.
The study showed that blood sugar levels were significantly
lower in all of the men after eating the high-fiber cereal than after eating
the low-fiber cereal.
In addition, insulin production was significantly lower after
eating the high-fiber cereal in the men with hyperinsulinemia than after eating
the low-fiber cereal.
Previous research has shown that it takes a fairly large amount
of fiber to reverse the metabolic abnormalities seen in diabetes. While the
amount of fiber provided in the study can be obtained from any number of
high-fiber cereals -- or other high-fiber foods -- this amount of fiber can be
difficult to tolerate. This amount of fiber can lead to increased bowel
movements and flatulence.
Researchers say the findings agree with previous studies
showing that the effects of carbohydrate foods on blood sugar levels are the
same in different people. But this study suggests that the effects of fiber-
and carbohydrate-rich foods can have varying effects on insulin in different
"Longer-term studies are required before conclusions can be
drawn as to whether a high-fiber breakfast cereal has any long-term benefits
for the management of insulin resistance or obesity," write researcher
Thomas M.S. Wolever, MD, PhD, of the University of Toronto, and colleagues.
The study was supported by General Mills and a grant from the
Canadian Institutes of Health Research.