Probiotics are live microorganisms, which taken in adequate amounts, provide health benefits.1 The term “probiotic” means pro-life and was coined as an antonym to the word antibiotic. For centuries, people have been eating foods that were fermented using live cultures of bacteria. Historically, health benefits have been attributed to these foods. Today we have probiotic supplements to do the job. Within the last few decades probiotics have gained the attention of the scientific and medical communities.
Research supports the role of our intestinal microflora in disease protection and prevention.2 Probiotics affect intestinal bacteria by increasing the numbers of beneficial bacteria and decreasing potentially harmful microorganisms. They help to restore the natural balance of good bacteria in the intestinal tract.3 In general, the strongest evidence for probiotics is related to their use in improving gut health and stimulating immune function.4
Picturing the human body as a host for bacteria and other microorganisms is helpful in understanding probiotics. Most probiotics are bacteria similar to the beneficial bacteria found naturally in the human gut.5 The body, especially the lower gastrointestinal tract, contains a diverse and dynamic community of microflora.
In a healthy adult’s body, cells of microorganisms are estimated to outnumber human cells by a factor of ten to one. Although we tend to think of bacteria as harmful germs, many actually help the body to function properly. They alter the intestinal environment by reducing harmful organisms, producing antimicrobial compounds, and stimulating the body’s immune system.6
If you are in good health and are consuming a healthful plant-based diet you don’t necessarily need to take probiotics. Your gut microflora are fed and nourished by the foods you consume. Eating a diet rich in vegetables, fruits, and beans naturally balances intestinal flora. The factors that appear to decrease an individual’s immunity or ability to resist the effects of pathogenic microbes in.16
Probiotics vary by genus, species and even different strains within the same species. It cannot be assumed that research published on a particular species or even strain of probiotic applies to other species or strains. Different strains of the same species of probiotics have different characteristics or benefits.
Probiotic supplements should contain species, strains and the number of viable organisms per dose (expressed as colony forming units or CFUs) that have been tested and proven to be effective.17 Product packaging should ensure an effective level of live bacteria through the “best by” or expiration date. Since probiotic supplements pass through the digestive system and are considered to be transient in nature, their benefits are dependent on regular consumption.
Prebiotics differ from probiotics. They are non-digestible food ingredients that stimulate the growth and/or activity of beneficial bacteria in the digestive tract.18 They are found naturally in a variety of plant-based foods, including onions, garlic, asparagus, leeks, artichokes, oats, and bananas.19 They provide food for the good bacteria. Prebiotics are beneficial, perhaps even necessary, to promote the growth and survival of probiotics in the GI tract. Probiotic supplements frequently contain prebiotics in the form of fructo-oligosaccarides (FOS), inulin and galacto-oligosaccharides (GOS).20
The use of probiotics shows promise for a number of health concerns, primarily those relating to the gastrointestinal tract. They have an excellent safety record and represent an option for prevention and treatment of antibiotic-associated diarrhea and relief of symptoms due to irritable bowel syndrome.
Probiotics may also be helpful for those with allergies and autoimmune diseases. Much research is currently underway in this area and progress will be continue to be made in identifying the specific species and strains of probiotics that are the most effective in each situation.