Highly branched cyclic dextrin (HBCD)

Highly branched cyclic dextrin (HBCD) is a high‑molecular‑weight carbohydrate created by enzymatically rearranging amylopectin into a branched cyclic structure. Also known as cluster dextrin, it consists of many glucose units linked in a way that forms compact clusters with a degree of polymerisation around 60–70.

Characteristics and performance benefits

HBCD stands out because its molecules are much larger than those of simple sugars but still dissolve easily. The cyclic, highly branched shape gives it a relatively narrow molecular size distribution and a high molecular weight while maintaining good solubility. In solution, HBCD creates fewer particles per gram than smaller carbohydrates, so it produces a drink with low osmolality even at higher concentrations. Low osmolality allows the beverage to pass quickly through the stomach, reducing the risk of bloating and gastric distress during exercise. Once in the intestine, digestive enzymes gradually break the clusters down into glucose, providing a sustained release of energy. This combination of rapid gastric emptying and prolonged energy supply makes HBCD attractive for endurance and high‑intensity training when large carbohydrate intakes are desired without compromising hydration. Some studies suggest that HBCD may support faster glycogen replenishment and improved performance compared with traditional maltodextrin, but research is limited and the ingredient is relatively expensive. Because it is essentially a glucose polymer, HBCD still counts toward total carbohydrate intake; athletes should stay within the typical 60‑90 g per hour range and combine it with electrolytes for balanced hydration.

Practical applications and notes

Mixing 50 g of highly branched cyclic dextrin into 500 mL of water produces a 10 % carbohydrate drink that remains hypotonic or isotonic due to the compound’s high molecular weight. Some endurance athletes and strength athletes use HBCD powders to deliver large carbohydrate doses without sweet taste or stomach discomfort. It is often combined with maltodextrin or simple sugars to provide both immediate and sustained energy. Because HBCD is derived from waxy maize or potato starch using specialised enzymes, it tends to be more costly than standard carbohydrate sources and is less common in mainstream sports drinks.

HBCD offers a unique balance of low osmolality and sustained glucose delivery, making it an appealing option for high‑carbohydrate hydration strategies. While it may reduce gastric distress and support steady energy supply, athletes should consider cost and combine it with electrolytes and other carbohydrates to meet overall nutrition targets.

Related Terms: Maltodextrin, Dextrose, Multiple transportable carbohydrates, Carbohydrate concentration, Isomaltulose (Palatinose)