Blood sugar, or more accurately blood glucose level, is a very important aspect of human physiology because glucose is the primary fuel for the central nervous system. If the blood level of glucose drops below a certain point for a long enough period of time, a person will lose consciousness, fall into coma and die. Very high blood glucose seen in diabetes is also harmful, although the immediate consequences are usually less dramatic.

It is less widely known that blood sugar has an important bearing on the aging process. Unfortunately, in addition to being a vital cellular fuel, glucose is also a substance that can cause damage to cells and tissues by randomly reacting with proteins, DNA and other vital molecules. (Scientists call this process glycation). Perhaps the worst consequence of glycation is cross-linking which is the formation of chemical bridges between proteins or other large molecules. A material that undergoes cross-linking usually becomes harder, less elastic and has a tendency to tear or crack. For instance, cross-linking is responsible for hardening of a rubber mat or a garden hose left in the sun. In an aging body, cross-linking causes hardening of arteries, wrinkling of the skin and stiffening of joints. Not surprisingly, diabetics, whose high blood glucose intensifies cross-linking, tend to have more skin damage (as well as vascular and other organ damage) than non-diabetics. However, even mildly high blood sugar promotes the aging process in the long run. This condition, called carbohydarate intolerance (or glucose intolerance) means that one's blood sugar tends to be higher than normal but not high enough to warrant the diagnosis of diabetes. Carbohydrate intolerance is extremely common, affecting up to fifty percent of the population in developed countries. In most carbohydrate intolerant people, fasting blood sugar is normal while blood sugar after meals is higher than it should be.

Research indicates that correcting carbohydrate intolerance is one the most important steps one can take towards slowing down the aging process.

Now, the question is how can one find out whether she has carbohydrate intolerance. An overt diabetes is relatively easy to diagnose. A doctor simply takes your fasting blood glucose to see whether it is elevated. A more sophisticated test called OGGT (oral glucose tolerance test) is needed to diagnose carbohydrate intolerance. First, your fasting blood sugar is measured. Then you are given a meal containing a standard amount of glucose, after which your blood glucose is measured every 30 minutes for 2 or 3 hours. This allows to see how quickly your blood sugar returns to normal after a carbohydrate load. The main risk factors for carbohydrate intolerance are being overweight and age over forty.

Improving carbohydrate tolerance

People who are carbohydratre intolerant can slow down their aging and reduce the risk of diabetes by taking steps to improve their carbohydrate metabolism. Furthermore, we believe that these steps are useful for anyone over thirty as they reduce the risk of developing carbohydratre intolerance or diabetes in the future.

Reducing glycemic effect of meals

As we ingest food, the enzymes in the gastrointestinal tract break it down into small molecules, such as simple sugars, aminoacids and peptides. Many foods, from ice-cream to pizza to pop-corn, contain glucose or other sugars that are converted to glucose in the body. Usually, glucose is in the form of starch, a branched polymer made up of many glucose molecules, or sucrose, a sugar consisting of one glucose and one fructose molecule. As the food is digested, the glucose it contains is released and absorbed into the bloodstream, which causes blood glucose level to rise. (Scientists call this glycemic effect of food.) How dramatic such a rise would be depends on several factors: (1) how much glucose a meal contains; (2) in which form this glucose is (e.g. starch or sugar); (3) are there other food ingredients, such as fiber, that affect the rate glucose absorption. Meals that produce less dramatic rise of blood glucose tend to be better for one's carbohydrate metabolism. Generally, among nutritionally equivalent alternatives, the food with smaller glycemic effect should be preferred. For instance, glycemic effect of a whole grain rye bread is 32 percent smaller than that of the equivalent amount of white bread. Guess which is better for your health!

Fiber

Over the past decades, research has promoted fiber from a nearly useless non-nutrient filler in plant-derived foods to an important food constituent conducive of health and longevity. Chemically, fibers are a diverse group of plant polymers based on polysaccharide chains. In contrast to starch, which is also a type of polysaccharide, fibers cannot be digested by humans, and pass through the gastrointestinal tract fully or partially intact. Large amounts of fiber in the diet make stools soft and bulky.

Fiber came to the spotlight when physicians working in Africa noted a very low incidence of such typical "Western" conditions as heart disease, diabetes, obesity, colon cancer, diverticulosis and hemorrhoids. They also noticed that local population consumed a very high fiber diet -- their stool volume was several times greater than that of people in the West. A role of fiber in preventing diseases and obesity was hypothesized, which spawned abundant research on the subject. Some health benefits of fiber, such as colon cancer prevention, are still controversial. Others, including its ability of fiber to prevent and/or improve carbohydrate tolerance and type II diabetes, are confirmed by solid evidence. Fiber slows down the rate at which glucose is absorbed from food into the bloodstream. This gives the body more time to process carbohydrates, leading to lower blood sugar and better carbohydrate metabolism.

It is estimated that a typical citizen of a developed country consumes about one third of the amount of fiber optimal for health and longevity. Luckily, it is not as difficult to increase one's fiber intake without supplements as many people think. Keep in mind that fiber supplements, especially when used improperly, may cause intestinal obstruction, a serious health problem. (This never happens with high fiber foods though).

Exercise

Regular exercise is known to improve carbohydarate tolerance and have a variety of other health benefits. (And it's fun too!). If exercising outdoors, which is usually more fun than otherwise, make sure to protect you skin from excessive sun and wind exposure.

Supplements

Certain nutrients and botanicals have positive effect on carbohydrate metabolism. For instance, lipoic acid is known to lower blood sugar levels (see also the article about conditionally essential nutrients in this section). Some adaptogens were consistently proven to improve carbohydrate tolerance or even reverse early stages of type II diabetes. Adaptogens are substances that promote successful adaptation of the body to various forms of stress and also normalize various physiological aberrations. Most known adaptogens are derived from plants and are quite safe at commonly used doses.

Drugs

Of course, there are drugs that lower blood sugar. Vritually all of them, however, can have substantial adverse effects. Using glucose-lowering drug in people with confirmed diabetes is a reasonable trade-off. These drugs should not be used in people with mild carbohydrate intolerance. There are far safer things to try!