FOS (Fructo-oligosaccharides)

Other names: Oligofructose, oligofructan

Harm score: 2 (Derivatives of natural substances)

FOS, or fructo-oligosaccharides, are a specific group of prebiotic fibres that contribute to the proper function of our digestive system. Fructo-oligosaccharides are naturally present in our diet because they are found in fruits and vegetables such as celery, wheat flour, bananas, onions, garlic and leeks. Their name is derived from the fact that they are made up of fructose units - specifically up to 2-60 units. Although these substances are carbohydrates, the human body does not have the enzymes to digest them, so they pass undigested to the large intestine where they are metabolized by the intestinal microflora.

Fructo-oligosaccharides are used in the food industry where they are added not only as health-promoting ingredients but also as natural sweeteners. They are involved in the production of yoghurt, kefir, milk, fruit drinks, but are also found in baked goods and sweets. Thanks to their properties, they have a positive effect on health. For example, they help to naturally lower blood cholesterol levels, stimulate the immune system, promote calcium and magnesium absorption and, most importantly for many people, contribute to weight loss and the maintenance of optimal body proportions. Nevertheless, care should be taken to consume them in reasonable quantities, as excessive intake can cause digestive problems in the form of diarrhoea or bloating.