Probiotics refers to a broad group of nutritional supplements not to any specific ingredient or substance. In particular, it refers to living bacteria and yeast (or some combination of microbes) which are consumed as foods or as supplements and are helpful to us.*
It may sound a little creepy at first, but the human body houses literally trillions of distinct, living microorganisms. The National Institutes of Health tells us the number of microbes contained by the human body outnumbers the total number of human cells by ten to one! That's a lot of critters.
There are thousands of species of bacteria, both "good" and "bad", inside our digestive tract which we refer to collectively as intestinal flora. Our bodies depend on having the proper balance of good microbes in our intestinal flora.
Probiotic supplements work to introduce helpful bacteria to our system to support a healthy balance in our intestines.*
How long have probiotics been around? The first scientist to propose the concept was Russian scientist and Nobel prizewinner Eli Metchnikoff, who suggested in the early 1900s that it would be possible to modify our intestinal flora consuming beneficial microbes.* He had noticed certain rural populations in Europe which were known to consume large quantities of milk fermented with bacteria had exceptional wellness.*
Metchnikoff died in 1916 but his work was picked up by other scientists in the United States who introduced the term probiotics in 1953.
It is difficult to describe an effect of probiotics because there can be so many depending on the particular microbes involved. There are thousands of species and each may have a slightly different impact.
Most often, probiotics are produced from common bacteria groups such as lactobacilli or bifidobacteria, or from various yeasts. A particular supplement may contain one of these, or a mixture. Within each of these broad categories are individual species, such as lactobacillus acidophilus or bifidobacterium bifidus.
And of course within each of these species are different strains ¦well, you get the idea.
Probiotics may support a favorable environment for nutrient absorption in the body*, and support other functions such as:
- Immune function*
- Intestinal support*
- Digestive health*
- Microflora balance*
Recent research has focused in particular on the molecular biology and genomics of lactobacillus and bifidobacteria. The science of modern genomics is steadily providing new insights into bacteria and the human immune system.
- Dairy products are a popular dietary source of probiotics. For example, yogurt contains both lactobacilli and bifidobacteria two common types of bacteria used in probiotics.
- Other examples include fermented and unfermented milk, miso, tempeh, soy beverages, and certain juices. In probiotic foods, the bacteria may have been present originally or they might have been added during preparation.
*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.