When selecting fiber drinks, the type of dietary fiber is the most critical factor. Soluble fibers like Inulin, Polydextrose, and Resistant Dextrin are preferred for beverages because they dissolve clearly without affecting texture. For digestive health claims, look for prebiotic fibers that stimulate gut flora. If the goal is weight management, prioritize fibers with high viscosity that promote satiety. Always verify the purity levels (typically >90%) to ensure the functional efficacy of the final product.