Probiotics are beneficial bacteria (sometimes referred to as “friendly germs”) that help to maintain the health of the intestinal tract and aid in digestion. They also help keep potentially harmful organisms in the gut (harmful bacteria and yeasts) under control. Most probiotics come from food sources, especially cultured milk products. Probiotics can be consumed as capsules, tablets, beverages, powders, yogurts and other foods.Read more
Live microorganisms which when administered in adequate amounts confer a health benefit on the host. FAO/World Health Organisation (2001)
Probiotics should not be confused with prebiotics. Prebiotics are complex sugars (such as lactulose, lactitol, a variety of fructo-oligosaccharides and inulin) that are used as fuel by the healthful bacteria to stimulate their growth and activity while suppressing the growth and activity of harmful organisms. Other foods that support probiotic activity include Japanese miso, tempeh, kefir, raw milk, kombucha, bananas, garlic and onions. When prebiotics and probiotics are combined in one product, it is called a synbiotic.
Probiotics work by colonising the small intestine and crowding out disease-causing organisms, thereby restoring proper balance to the intestinal flora. They compete with harmful organisms for nutrients and may also produce substances that inhibit growth of harmful organisms in the gut.
Probiotic bacteria have been found to stimulate the body’s immune system. They may also aid in several gastrointestinal illnesses such as inflammatory bowel diseases, antibiotic-related diarrhoea, Clostridium difficile toxin-induced colitis, infectious diarrhoea, hepatic encephalopathy, irritable bowel syndrome and allergy.
Probiotics have been found to enhance the digestion and absorption of proteins, fats, calcium and phosphorus. They may help overcome lactose intolerance. Finally they may help restore healthful bacteria after a course of antibiotic therapy has altered the normal gastrointestinal flora.
Probiotic bacteria are very strain dependent, not species dependent. A strain is a type of a bacterial species, similar as to the example below:
- Bacterial group = German car = lactic acid bacteria
- Bacterial genus = Volkswagen = Lactobacillus
- Bacterial species = VW Golf = Lactobacillus acidophilus
- Bacterial strain = VW Golf 1.4 D = Lb. acidophilus LC1
Everybody knows that a Volkswagen Golf 1.4 D has other characteristics than a Volkswagen Golf 2.0i turbo, but you can’t see the difference on the outside.
The same is true for bacteria; they all look the same, but the biological characteristics (‘the engine’) are different. Hence, claims on health effects of a certain probiotic are only valid for that specific strain, not species.
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