Close-up of beet
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Beets are a type of root vegetable with an appearance similar to red potatoes. A specific type of beet commonly called “sugar beet” is rich in sucrose and has been used as a source of refined table sugar for a few hundred years. The beets you are likely to buy at the grocery store are not as sweet because they contain much less sugar. Even sugar beets don’t contain much glucose, and all varieties contain lots of fiber, which tends to moderate blood glucose levels and prevent insulin spikes.

Sugar Beets

Sugar beets, also known by the Latin name Beta vulgaris, became much more popular during the 19th century, when it was discovered they were a concentrated source of sucrose. Sucrose is a disaccharide sugar made up of one molecule of fructose and one molecule of glucose. Sucrose is readily digested by your body and quickly impacts blood glucose levels and stimulates the release of insulin from the pancreas. Insulin is needed to shuttle the glucose from the blood and into cells for fuel. Thus, sugar beets contain hardly any glucose, but the sucrose content is quickly metabolized into glucose.

Regular Beets

Another variety of Beta vulgaris is typically eaten as a vegetable in the United States. These regular beets are much lower in sugar, but they contain many other nutrients in abundance. For example, beets are rich in folate and manganese, as well as very good sources of potassium and dietary fiber. In fact, 1 cup of raw beets provides about 15 percent of the recommended amount of daily fiber for most adults Approximately 28 percent of the dietary fiber is soluble and the remainder is insoluble. High-fiber foods tend to have a beneficial impact on blood glucose levels.

Fiber and Blood Glucose

Soluble fiber, particular when eaten in large amounts, can lower or at least moderate blood glucose levels because it slows down your digestion. Slower digestion leads to a slower absorption rate of glucose, which prevents levels in the blood from rising too high or too rapidly. Steady blood glucose levels limit spikes of insulin release and prevent the so-called sugar “highs” and “crashes” often experienced with eating sugary foods. The one possible complication of a high-fiber diet is that it can lead to constipation and stomach cramps if you don’t drink plenty of water.

Glycemic Index and Load

The glycemic index is a comparative measure of how quickly a food impacts blood glucose levels, but it doesn’t take into account serving sizes. Regular beets have a glycemic index of 64, which is relatively high compared to other carbohydrate-rich foods, but you’re very unlikely to eat enough beets to impact your blood glucose levels dramatically. Perhaps a better measurement of beets impact on blood sugar is its glycemic load. Beets have a low glycemic load rating of 5 because a significant proportion of its carbohydrates are indigestible dietary fiber and meal portions are usually fairly small -- about 1/2 cup. As such, in moderation, beets are an appropriate veggie for diabetics and others who monitor their blood glucose levels.