Maltodextrin is a complex carbohydrate (polysaccharide) produced from the partial hydrolysis of starch—typically corn, rice, or potato. In the endurance world, it is the primary “engine” of sports gels, drink mixes, and chewable energy blocks. Despite being a complex carb, maltodextrin has a high Glycemic Index (GI), meaning it is absorbed into the bloodstream nearly as fast as glucose, providing the immediate fuel required for high-intensity efforts.
The true tactical advantage of maltodextrin lies in its low osmolality. Because it is composed of long chains of glucose molecules, it exerts less osmotic pressure in the gut than simple sugars (like sucrose or dextrose). This allows athletes to ingest a high volume of calories with a significantly lower risk of Gastrointestinal (GI) Distress or “bloating.” When combined with fructose—utilizing a dual-transport system—maltodextrin allows the body to oxidize up to 90 to 120 grams of carbohydrate per hour, a rate essential for surviving the “Middle Miles” of an Ironman or a 100-mile ultra-marathon. Whether you are mixing a custom bottle for a 56-mile bike leg or ripping a gel during a marathon, maltodextrin is the gold standard for sustained metabolic power.
