FOS (fructooligosaccharides) is a source of food that the bifidobacteria consume and make short chain fatty acids. These are needed for the health of the intestinal tract cells, especially the ones that line the intestines.
We obtain FOS naturally in our diet. Garlic and honey, followed by rye, brown sugar, banana, onion, barley and tomato all contain some FOS. However, one would have to eat a significant serving of these foods with every meal to get a useful dose.
95% FOS are essential: They are non-nutritive to the body and contain only 1.5 calories per gram. If FOS is less than 95%, it then contains too many simple sugars as glucose, fructose, and sucrose. These are the sugars that feed the yeast that contribute to the ill effects on the body.
Consuming 1 gram (1/4 teaspoonful) of FOS a day will cause a five-fold increase in growth of the bifidobacteria in a month. Consuming Florajen 3 and FOS together will increase the friendly bacteria in 24 to 48 hours. This is why this combination therapy is so fast and effective. Most health care professionals have not been trained to recognize the key role a healthy gastrointestinal tract plays in maintaining overall health.