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Several years ago, Americans began a "low fat craze" in the hopes of losing weight. Unfortunately, the opposite
actually occurred. There has been a general population weight gain, and Americans are now more overweight than ever. This
phenomenon became known as the "American Paradox". This trend towards obesity does not appear to be reversing. On
the other hand, the French consume more fat than us, but are not as obese as Americans. This has become known as the famous
"French Paradox".
How do we make sense of these two contrary observations? In the American case, reading the
ingredients of most products labeled "low fat" will provide the first clue - the fat was replaced with sugar. Over
the years, our consumption of simple carbohydrates has increased dramatically. We are consuming more high glycemic foods,
such as sugary disserts, soft drinks and snacks, than ever.
The consequences of this high glycemic American diet are
an increase in blood sugar and insulin levels. This is a combination that is detrimental to health. If allowed to continue
unchecked, a condition known as Syndrome X may develop. The primary characteristic of Syndrome X is insulin resistance, which
leads to prolonged elevations of blood glucose levels. As excess glucose is converted to fat by the liver, elevated triglycerides
levels are commonly seen. High levels of both insulin and glucose in the blood can be irritating to blood vessels and this
can lead to an increased risk of hypertension. High blood pressure can be the result of insulin induced stimulation of the
sympathetic nervous system, and also from insulin's ability to stimulate growth factors that may induce hypertrophy (enlargement)
of vascular walls. It is interesting to note that although total cholesterol levels may not be excessively high, in Syndrome
X, the low-density lipoprotein (LDL) may in fact be smaller, denser and more artherogenic when compared to LDLs of healthier
patients. In addition, high-density lipoproteins (HDL) levels tend to be lower and triglycerides are often higher. It is the
elevated triglyceride level that often alerts an astute health care professional to consider the possibility that Syndrome
X may be a factor.
A nutritional tool known as the glycemic index can better explain the glucose-insulin response. By
measuring the rate carbohydrates are absorbed into the bloodstream, we can demonstrate that not all carbohydrates are created
equal. The glycemic index can be used to predict the body's glucose and subsequently, its insulin response to certain foods.
Foods with a high glycemic rating may stimulate the pancreas to release more insulin than necessary. When this occurs, the
unused insulin remains in the bloodstream and may either cause blood sugar levels to drop too low, or in the case of insulin
resistance, promote the storage of excess calories as fat. Low glycemic foods may help to maintain normal serum glucose levels,
and can they actually raise your metabolism to help burn calories.
Examples of high glycemic foods are all simple sugars
such as sucrose, corn syrup, honey, invert sugar, maltodextrin, and the commonly found sweetener, high fructose corn syrup.
Other simple carbohydrates, such as rice cakes, popcorn, baked potatoes, white bread, white rice, pasta, and many other highly
processed foods are treated as simple sugars by the body. The best low glycemic foods are complex carbohydrates such as whole
grains and legumes. Beans are particularly beneficial because when eaten with other foods, they can actually average down
the glycemic response of other higher glycemic foods such as white rice and pasta. Although considered a simple sugar, fructose
has a low glycemic rating. Since fructose does not require insulin to be metabolized, it does not elicit an insulin response.
Therefore most fresh fruits are acceptable to eat. Crystalline fructose can even be substituted for table sugar in most cases.
Continuous poor glycemic control may eventually lead to obesity, heart disease and diabetes mellitus. LDL oxidation
may increase, leading to excess free radical damage, resulting in pre-mature aging. Increased insulin levels can increase
the action of an enzyme, lipoprotein lipase, that stimulates the uptake of triglycerides to be stored as fat. This may result
in obesity. Sustained high levels of insulin can also result in decreased ability of wound healing. That explains why many
diabetics suffer with ulcerations that take a long time to heal. Many with poor glycemic control also complain of lethargy.
Well-controlled insulin levels result in reduced tendency to store fat. This leads to increased energy and better mental alertness.
Serum cholesterol levels are often lower and there is a reduced incidence of hypertension and heart disease. Therefore, the
road to optimal health may begin with maintaining proper glycemic control.
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