Xylitol and Blood Sugar

By Debbie Humphries, PhD, MPH, Nutrition Consultant

Have you wondered what makes blood sugar go up when you have diabetes? How xylitol might affect blood sugar?

Glucose is the preferred fuel for your body. After a meal, as foods are digested in the mouth, stomach and the intestine, nutrients are absorbed into the blood from the intestine. Carbohydrates (sugars and starches) are broken down into single sugars (monosaccharides – glucose, fructose, galactose). Simple carbohydrates and some starches are broken down very rapidly and quickly make their way into the blood, causing a rise in blood sugar (or blood glucose). Such foods would include candy, baked goods, and refined foods such as white bread, pasta, white rice. Larger carbohydrate molecules (complex carbohydrates), with more fiber and more molecules, take longer to break down to simple sugars, and don’t show up in the blood as quickly.

Simple sugars diffuse through the intestinal wall into the blood stream. Sugar alcohols are not completely absorbed, and much of the xylitol consumed remains in the intestine (Natah et al., 1997; Wolever et al., 2002). Because much of the sugar alcohols aren’t absorbed, they have fewer calories for the same amount of sweetness as you get from glucose. Once in the blood, fructose, galactose and sugar alcohols are carried to the liver where they are converted to glucose or related molecules. The glucose is then released back into the blood stream, where it is carried throughout the body, and absorbed into cells. Insulin is the hormone that triggers cells to pick up the extra glucose from the blood stream. In people that are insulin resistant, their cells don’t respond to the insulin, and blood sugar levels remain high. In people that are diabetic, some lose the ability to make insulin, and can’t signal the cells to take up the glucose from the blood.

One research study compared blood glucose levels after eating similar amounts of glucose, xylitol and lactitol (Natah et al., 1997). Eight healthy men were given the same amount (25g) of one of the three sugars after fasting for 10-12 hours. Their blood sugar and insulin levels were then sampled every 30 minutes for the next three hours. All volunteers were given each of the sugars, one sugar per week, over a three week period. After taking the xylitol, volunteers showed a rise in blood glucose that was only 7% of the rise after eating the dose of glucose. This study suggests that eating foods containing xylitol will not lead to increases in blood sugar, and thus would be appropriate for people with diabetes to use. While they had only a few participants, the results were dramatic (7% of the blood glucose level following xylitol consumption), which suggests that if we repeated their experiment with more participants, we would still expect there to be a smaller rise in blood glucose when participants eat xylitol, when compared with a similar amount of glucose.

Learn more about Xylosweet.

Read Xylitol FAQs.