Compositions containing hemicelluloses, citric acid and glucose syrup, fructose or sucrose in combination with polyphenols and prebiotics, methods of preparing the compositions, and methods of treating humans or animals with the composition are provided. Also provided is a method for increasing growth rate, improving feed efficiency and decreasing scour after weaning in an animal by administering an effective amount of the composition to the animal. The prebiotics preferably are not consumed by human alimentary enzymes or harmful bacteria, such as putrefactive or pathogenic bacteria, and are consumed by beneficial bacteria, such as bifidobacteria, in the gastrointestinal tract. The polyphenols preferably decrease the amount of harmful bacteria in the gastrointestinal tract. The compositions can optionally contain a carrier or be used as a feed addition and are administered to humans or other animals in an amount sufficient to treat the gastrointestinal disorder.
