L-arabinose (Sukre prebiotic fiber)

What is L-arabinose?

L-arabinose is a five-carbon sugar (a pentose) that occurs naturally in plant fibers such as hemicellulose and pectin, found in corn hulls, sugar beet pulp and other plant materials. It is extracted commercially and sold as a low-calorie sweetener and functional ingredient, sometimes under brand names. The body absorbs little of it, so much of it reaches the large intestine, where gut bacteria can ferment it; that is why it is sometimes marketed as a prebiotic fiber. Its main interest, however, is how it interacts with table sugar.

What the research says

L-arabinose inhibits sucrase, the enzyme in the small intestine that splits sucrose (table sugar) into glucose and fructose. A 2011 study in the American Journal of Clinical Nutrition confirmed this effect in the lab and in people: adding L-arabinose at 4% of the sucrose in a sugary drink produced an 11% lower glucose peak, a 33% lower and delayed insulin peak and other favorable hormone changes, without digestive symptoms. A 2022 randomized crossover trial in 12 healthy young adults found that adding 7.5 g of L-arabinose to a drink with 50 g of sucrose lowered and delayed the glucose peak by slowing the absorption of sugar-derived glucose.

The effect has limits. It works on sucrose, not on starch. A 2015 study that mixed L-arabinose into solid or semi-solid breakfast meals containing sucrose and wheat starch found no change in glucose, insulin or C-peptide responses, with L-arabinose added at 5% or 10% of the meal by weight. The authors could not reproduce the benefit seen with sugary drinks. The ingredient also has to be present at the same time as the sugar, in gram amounts, to block the enzyme.

How it’s used in supplements

L-arabinose is used in some foods and drinks as a sugar companion and in blood sugar supplements. In capsule products it is usually part of a proprietary blend, often totaling only a few hundred milligrams for all ingredients, and is sometimes taken before meals rather than with sugary foods. That is very different from the gram doses mixed directly into sugar drinks in the studies. L-arabinose appears to be well tolerated, although large amounts of poorly absorbed sugars can cause gas or loose stools in some people. People with diabetes should not rely on it to offset sugary foods and should talk to their doctor before adding supplements that may affect blood glucose.