Isomaltulose

Isomaltulose is a carbohydrate where slow energy release maintains stable blood sugar levels, using a unique chemical structure.

This article is part of the Complete Guide to Proper Nutrition — a core guide from the Sport Zona expert team.

What it is

Isomaltulose, also known as Palatinose™, is a disaccharide carbohydrate that consists of one molecule of glucose and one molecule of fructose, linked by a specific alpha-1,6 glycosidic bond. This unique bond distinguishes it from sucrose (regular table sugar), which has an alpha-1,2 bond. The structure of isomaltulose makes it more resistant to enzymatic breakdown in the small intestine, resulting in slower and more gradual absorption.

Naturally found in small amounts in honey and sugarcane, isomaltulose is produced industrially through an enzymatic transglucosylation reaction from sucrose. This results in a white crystalline powder with a sweet taste, approximately half as sweet as sucrose. Its physicochemical properties include high stability in acidic environments and at high temperatures, making it suitable for a wide range of food applications.

How it works

The primary mechanism of action of isomaltulose lies in its slow and complete absorption. Unlike rapidly absorbed sugars that quickly break down into glucose and fructose, leading to a sharp spike in blood sugar levels, the enzyme sucrase in the small intestine breaks down isomaltulose much more slowly. This results in a gradual release of glucose into the bloodstream.

The gradual rise in glucose elicits a more moderate insulin response. This is crucial, as high insulin spikes can lead to rapid depletion of energy stores and a subsequent drop in blood sugar (hypoglycemia). With isomaltulose, energy is delivered more long-term and stably, maintaining consistent blood sugar levels and reducing the risk of energy crashes during prolonged physical exertion. This mechanism also supports more efficient fat utilization for energy, especially at submaximal training intensities.

Why it's important for athletes

For athletes, isomaltulose offers significant advantages due to its low glycemic index (GI = 32) and its ability to provide sustained energy release. This is particularly valuable during prolonged training sessions or competitions where a consistent energy supply is critical for maintaining performance and endurance. Instead of a quick, short-lived energy surge followed by fatigue, isomaltulose ensures a steady supply of glucose to the muscles and brain, allowing for longer periods of activity without a drop in concentration or physical efficiency.

Recommended dosages for athletes vary, but often range between 30-60 grams of isomaltulose, dissolved in water or a sports drink, about 30-45 minutes before training or during prolonged exertion. Studies suggest that incorporating isomaltulose into the diet can support increased fat burning during exercise while preserving muscle glycogen for more intense moments. Although there is no official recommended daily intake from organizations like ISSN specifically for isomaltulose, it is classified as a safe carbohydrate and can be effectively included as part of the total carbohydrate intake, adapted to the athlete's individual needs, typically in the range of 3-10 g/kg body weight per day for athletes with high energy expenditure.

Related concepts

• Fructose — A component of isomaltulose, which is metabolized through a different pathway in the body.
• Glycemic Index (GI) — A measure by which isomaltulose stands out with its low GI, ensuring stable blood sugar.
• Glycemic Load (GL) — An indicator that is also low for isomaltulose, reflecting its gradual impact on blood sugar.
• Sucrose — Another disaccharide carbohydrate that is more rapidly absorbed and has a higher glycemic index compared to isomaltulose.