Fructose is not better for you than table sugar, and drinks that contain lots of fructose can cause intestinal gas. Fructose is a single sugar molecule, while granulated white table sugar is called sucrose and is made up of two single sugars, glucose and fructose bound together. When table sugar reaches your intestines, the double table sugar, sucrose, is immediately split into its single sugars, glucose and fructose. Almost all of the glucose is absorbed immediately into your bloodstream. In the presence of glucose in your intestines, most of the fructose is also converted to glucose, which is rapidly absorbed into your bloodstream. Regular sugar is absorbed so quickly that very little remains in the intestinal tract.

However, when you take fructose without glucose, the fructose is not converted as rapidly to glucose, and the fructose is absorbed less quickly into the bloodstream. Therefore, some fructose passes along the intestinal tract until it reaches the colon where bacteria can ferment the fructose to cause gas and cramps. This is particularly important when you take fructose before or during exercise. Exercise speeds up the rate that fructose reaches your colon and increases your chances of getting gas pains and cramps.

If fructose is not absorbed as well as table sugar, does that mean that fructose is better for diabetics? Again, the answer is no. Several studies show that taking large amounts of fructose can harm a diabetic. Diabetes occurs when the body lacks insulin or cannot respond to insulin. Insulin is supposed to drive sugar from the bloodstream into cells. When insulin does not do its job, the sugar, glucose, accumulates in the bloodstream, causing a diabetic to feet sick and weak and even pass out. Fructose can get into cells without insulin, so some people incorrectly recommend that diabetics eat foods made with fructose. However, in the intestines and the bloodstream, fructose is converted into glucose, and the diabetic gets no benefit.

Not only is fructose of no benefit to a diabetic, it can cause harm. Glucose causes fat cells to release leptin that makes you feel full, and prevents the stomach from releasing ghrelin that makes you hungry. Fructose does not affect leptin or ghrelin, so it increases hunger to make you eat more. Large amounts of fructose can block the body's ability to respond to insulin, so even more insulin is required. Furthermore, the liver converts fructose far more readily to a body fat called triglycerides, than it does with glucose. High triglyceride levels raise blood levels of the bad LDL cholesterol and lower blood levels of the good HDL cholesterol, which increases heart attack risk. The treatment of diabetes includes avoiding all types of sugar and other refined carbohydrates, losing weight if overweight, and exercising. It is not treated by eating fructose.

Dr. Gabe Mirkin has been a radio talk show host for 25 years and practicing physician for more than 40 years; he is board certified in four specialties, including sports medicine. Read or listen to hundreds of his fitness and health reports at http://www.DrMirkin.com

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