Fructooligosaccharides (FOS) (fructooligosaccharides )
Synopsis of fructooligosaccharides (FOS)
Fructooligosaccharides (FOS) are a type of prebiotic carbohydrate, classified as short-chain oligosaccharides made up of fructose units with a terminal glucose. Naturally found in small amounts in foods like onions, garlic, chicory root, leeks, asparagus, and bananas, FOS are indigestible by human enzymes and instead serve as a fermentable fiber for beneficial gut bacteria, particularly Bifidobacteria and Lactobacilli.
FOS are widely used in digestive health supplements and functional foods for their ability to improve gut flora composition, enhance mineral absorption (notably calcium and magnesium), support immune function, and regulate bowel movements. They help produce short-chain fatty acids (SCFAs) such as butyrate and acetate, which support colon health, reduce intestinal pH, and act as energy sources for colonocytes.
In addition to promoting a healthy microbiome, FOS may help lower triglycerides, support glucose regulation, and enhance satiety, making them useful in metabolic health and weight management programs. However, because they are fermentable, FOS may cause bloating or gas in some individuals, especially at higher doses or in those with IBS or FODMAP sensitivities.
FOS are commonly added to probiotic formulations, infant formulas, meal replacements, and plant-based dairy alternatives, where they improve both gut health and texture.
Historical Use
Although FOS as an isolated compound was only identified and named in the 20th century, the traditional consumption of FOS-rich foods has occurred for thousands of years across cultures. Chicory root, one of the richest natural sources of FOS and inulin, was used in Ancient Egypt, Greece, and Rome as a liver tonic and digestive aid. Garlic and onions, staples in global cuisines, were also used medicinally for digestion, immunity, and circulation—delivering FOS alongside other bioactive compounds.
In Traditional Chinese Medicine, herbs like Chinese yam and burdock, which contain FOS and other fermentable fibers, were used to tonify the Spleen and Stomach, support Qi, and relieve constipation. Similarly, Jerusalem artichoke, another FOS-rich plant, has been used in European folk remedies for blood sugar and gut health.
The modern scientific recognition of FOS began in Japan in the 1980s, where researchers explored its prebiotic effects as part of the country’s development of “functional foods.” This led to the emergence of FOS as a key ingredient in the growing field of gut microbiome research.
Today, fructooligosaccharides represent a natural, food-based solution to digestive and metabolic health, bridging traditional dietary practices with cutting-edge nutritional science.
Fructooligosaccharides (FOS) is used for these health conditions
Allergies (food) (Scientific)
Anemia (Scientific)
Cholesterol (high) (Scientific)
Constipation (adults) (Scientific)
Constipation (children) (Scientific)
Crohn's Disease (Scientific)
Diabetes (Scientific)
Diarrhea (Scientific)
Digestion (poor) (Scientific)
Gas and Bloating (Scientific)
Gastritis (Scientific)
Inflammation (Scientific)
Inflammatory Bowel Disorders (Scientific)
Irritable Bowel Syndrome (Scientific)
Leaky Gut Syndrome (Scientific)
Metabolic Syndrome (Scientific)
fructooligosaccharides (FOS) is used to support these body systems
Digestive System (Scientific)
Gastrointestinal Tract (Scientific)
Immune System (Scientific)
Intestinal System (Scientific)
Large Intestines (Colon) (Scientific)
Peyer’s patches (Scientific)
Small Intestines (Scientific)
