In the field of sucrose replacement, low-energy bulk ingredients must be used to lower the energy density of food. Ideally, low-energy bulk ingredients as a substitute for sucrose should have significantly less energy, possess physical and chemical properties that precisely match those of sucrose in all food applications, provide secondary health benefits (such as being noncariogenic, being useful for diabetics, and having fiber-like effects), confer no negative side effects, and be completely safe at any amount of consumption. The food industry has developed a range of low-energy bulk ingredients. Most of these are legally permitted in food applications and are undigestible sugars (eg, polyols and fructo-oligosaccharides). Their main nutritional properties (energy value, digestive tolerance, and cariogenicity) are related to their fate in the digestive tract, especially their capacity to be used and fermented by bacteria.