Probiotics, which means "for life," are live bacteria that help maintain the balance of intestinal organisms. About 400 probiotics fight to hinder dangerous bacteria and keep the digestive system healthy.  They are similar to organisms that are found naturally in the digestive tract. When taken in the proper amounts, probiotics may provide a variety of health benefits.
Types of Probiotics
Some examples of probiotics that are naturally found in your body are:
This is a group of probiotics that aids digestion.
Lactobacillus Acidophilus (L. Acidophilus): This bacteria is mostly found in the intestines, mouth and vagina. It helps balance the body's pH, keeping it at an acidic level, which can hinder the spread of harmful bacteria. Yogurt and fermented soy are good sources of L. acidophilus. It's available as a supplement as well, including pill, powder, and liquid forms.[7, 8, 23]
Lactobacillus Bulgaricus (L. Bulgaricus): This bacteria is found in the digestive tract -- intestines and stomach. It helps maintain acidic pH levels to reduce unhealthy bacteria levels, boost immunity, and block pathogen adhesion sites in the intestinal mucous lining. Sources include Bulgarian yogurt and Swiss cheese. It's also available as a supplement in capsule form.
Lactobacillus Casei (L. Casei): This bacteria is found in the mouth and intestines. It helps prevent diarrhea and inflammation, depending on the strain, by controlling the spread of harmful bacteria while also encouraging the growth of healthy bacteria. Sources include yogurt, fermented green olives and cheese.
Lactobacillus Rhamnosus (L. Rhamnosus): This bacteria is found in the intestines. It facilitates healthy bacterial growth, eliminates and interferes with the growth of harmful bacteria. Supplements are available in pill, suppository and liquid forms.
Lactobacillus Reuteri (L. Reuteri): This bacteria is found in the intestines of mammals and birds -- and only some humans. It can help relieve certain conditions, including colic, acute diarrhea, IBS and eczema. It also hinders E. coli bacteria growth. Sources include milk, meat and supplements..
L. bifidus is a group of bacteria found in the intestines. It can also grow in a lab. Bifidobacteria can be taken to help restore healthy bacteria lost due to intestinal problems caused by illness or eliminated by certain medications. It's available as a supplement in a variety of forms, including pill, powder and fermented milk.
Sub-strains of Bifidobacteria include:
Bifidobacteria can be taken to help restore healthy bacteria lost due to intestinal problems caused by illness or eliminated by certain medications.
Bifidobacterium Animalis (B. Animalis): This bacteria, found in human and animal intestines, promotes healthy digestion and may be helpful in the treatment of certain types of colitis. Yogurt provides a good source of B. animalis.
Bifidobacterium Breve (B. Breve): This bacteria, found in the lower digestive tract, competes well with other bacteria. Some people have plenty of B. breve, but not everyone, so supplementation may be necessary to bring levels up. Like L. reuteri, B. breve can hinder E. coli as well as diarrhea and gas.
Bifidobacterium Infantis (B. Infantis): This bacteria is found in the intestines. Acid produced by B. infantis may hinder harmful bacteria growth in the colon. Sources include cheese and yogurt.
This probiotic is found in the intestinal tract. It is available for purchase as a freeze-dried yeast. S. boulardii can help prevent and treat gastrointestinal disorders.
Probiotics and special populations
Children: Probiotics may help treat a variety of health problems. Efficacy depends on the disease, strain of the probiotic and dosage. They appear to work effectively on:[5, 10, 11, 12, 14]
Gastrointestinal tract infections
Antibiotic-associated diarrhea (Prevention, not treating. More research needed)
Necrotizing enterocolitis (Death of intestinal tissue in very low birth weight babies)
Constipation (Research is mixed)
Probiotics don't seem to help children experiencing:
Irritable bowel syndrome
Some types of yogurt are a good source of probiotics for children.
Athletes: Studies fail to show any potentially positive effects of probiotics on athletic performance, but they may provide secondary health benefits including:
Healthy gastrointestinal tract maintenance
Quicker post-exercise recovery
Uses, benefits, and effectiveness
Probiotics have many uses and benefits, but they vary according to type and strain. Some uses include:
Diarrhea prevention and treatment (Strong evidence)[1, 9]
Digestive tract infection prevention
Respiratory tract infections
Vaginal yeast infection treatment and prevention
Irritable bowel syndrome (Studies ongoing)
Urinary tract infections in women (Effective) 
Inflammation control (Inflammatory bowel disease, for example, Crohn's disease. More studies are needed)[1, 3, 4]
Intestinal infection treatment 
May ease side effects of Helicobacteria pylori (H. pylori) treatment. (This bacteria causes most stomach ulcers. More studies needed.)[3, 14]
Tooth decay prevention
Cold/flu prevention or reduction of severity
Probiotics are being studied for their potential use in colon cancer, obesity, skin infection treatment, and cholesterol reduction.[1, 3]
Specific probiotics and the diseases they may help:
Immune system regulation
Bifidobacterium lactis HN019
Lactobacillus reuteri ATCC55730
Lactobacillus rhamnosus GG (LGG)
Lactobacillus casei DN-114001
Bifidobacterium lactis Bb-12
S cerevisiae (S. boulardi)
Lactobacillus rhamnosus GG (LGG)
Lactobacillus casei DN-114001
Lactobacillus acidophilus CL 1285 plus Lactobacillus casei Lbc80r
Safety concerns and side effects
Probiotics may not be safe for the elderly, young children, people who are critically ill, people with gastrointestinal disorders, short bowel syndrome, indwelling venous catheters, weakened immunity or high fever. Ask your doctor before starting probiotic therapy.[1, 2, 3, 5, 8]
Although probiotics don't usually have many side effects, some that could occur are flatulence, abdominal cramps and septicemia (blood infection). Effects of long-term use are unknown. Use with care. Take only as directed.[3, 14]
Avoid use if you are allergic to milk.
Tell your medical team all the medications you are taking, including those that are complementary and alternative.
Do not use different forms of Lactobacillus Acidophilus together unless prescribed by a doctor.
Bifidobacteria may cause bloating and gas.
Store lactobacillus acidophilus in a dry, dark, cool place.
Probiotic ingredients should be clearly marked on the package. Only use products you are familiar with and trust.
Probiotics allergy protection benefits are not clear in regard to use in children.
Although Lactobacillus GG has been deemed safe for use during pregnancy, to be safe, do not take lactobacillus acidophilus if you are pregnant or breast-feeding without first consulting your doctor.[7,8]
Do not take Lactobacillus Acidophilus if you have health problems, allergies, or take medications or supplements without first talking to your doctor.
Do not give a child probiotics without first consulting the child's pediatrician.
Risk of sepsis from Lactobacillus Rhamnosus GG and Bifidobacterium sp. is low.
Bifidobacteria is safe for adults and children if used properly.
Signs of allergic reaction to Lactobacillus Acidophilus include hives, swollen face, tongue, throat and lips, and breathing difficulty.
Infant formulas containing probiotics seem to be safe for healthy babies but research doesn't show benefits.
Follow directions as indicated on the label. In general, 5 to 10 billion colony-forming units (CFU's) per day for children and 10 to 20 billion daily for adults are recommended. Consult your doctor for dosages recommended for your specific situation.[14, 16]
Antibiotics: Antibiotics may reduce the effectiveness of bifidobacteria. Take antibiotics at least two hours before or after bifidobacteria.
Find the best deals on probiotics check out PricePlow's buying guide Our price comparisons make it easy to find the lowest price from any health store on the web. You can save from 30 to 50% by buying through the listings on this page versus your local retail store.
What Is the best probiotic
It depends on many factors. Strains vary even within the same species. They're also used for completely different health issues and it depends on your body's chemistry.
Each person may react to a specific probiotic strain differently.
Choose probiotics from trusted manufacturers and brands that are known to be effective for your particular needs. Use what works for you. [3,15]
That said, you may want to try Nature's Way Primadophilus. Products are guaranteed pure, potent and effective. On top of that, they offer a variety of high-quality probiotics for different populations, including different age groups and vegetarians.
Probiotics are regulated as foods, not medications.
Because probiotics are marketed as dietary supplements, they do not require FDA approval. But probiotics marketed as a treatment for a specific condition need FDA approval.
The FDA hasn't approved any specific probiotic health claims.
There is not much scientific evidence to confirm the use and benefits of many probiotics.
The number of live organisms in probiotic products may vary from what is listed on the label or advertised.
Choose probiotics that are marked viable "through the end of shelf life."
Just because a product has more live probiotics that doesn't mean it's better.
- WebMD; "Probiotics - Topic Overview;" Updated 2011
- Elaine Magee, MPH, RD; WebMD; "5 Things You Should Know About Probiotic Products;" Reviewed 2009
- National Institutes of Health; National Center for Complementary and Alternative Medicine; Get the Facts;"Oral Probiotics: An Introduction;" Updated 2012
- The Harvard Medical School Family Health Guide; "Health Benefits of Taking Probiotics;" Updated 2005Journal of Pediatric Gastroenterology and Nutrition"Clinical Efficacy of Probiotics: Review of the Evidence with Focus on Children;" 2006
- Andrew W. Nichols, MD; Current Sports Medicine Reports; "Probiotics and Athletic Performance: A Systematic Review;" 2007
- Drugs.com; "Acidophilus Extra Strength;"
- Mayo Clinic; "Acidophilus (Lactobacillus acidophilus)"Katherine Zeratsky; RD; Mayo Clinic; "Is It Important to Include Probiotics and Prebiotics in a Healthy Diet?;" 2011
- ScienceDaily; "Probiotic-Derived Treatment Offers New Hope for Premature Babies;" 2013
- Tabbers MM, et. al.; Nutrition Journal; "Is Bifidobacterium Breve Effective in the Treatment of Childhood Constipation? Results from a Pilot Study;" January 2011
- Katrina Woznicki; WebMD; "Children May Benefit From Probiotics, Prebiotics;" November 2010
- Gina Shaw; WebMD; "A Nutritionist Speaks: How to Promote Your Child's Digestive Health;" Gina Shaw; February 2012
- Benjamin Kligler, MD, Andreas Cohrssen, MD; American Academy of Family Physician; "Probiotics;" November 2008
- California Dairy Research Foundation; "Frequently Asked Questions & Consumer Information;"
- MedlinePlus; "Bifidobacteria;" December 2012
- Nature's Way; "Primadophilus"
- Probiotic.org; "Lactobacillus Bugaricus"
- Probiotic.org; "Lactobacillus Casei"
- Probiotic.org; "Lactobacillus Reuteri"
- Probiotic.org; "Bifidobacterium Breve"
- Probiotic.org; "Bifidobacterium Infantis"
- Probiotic.org; "Acidophilus"
- Probiotic.org; "Lactobacillus Rhamnosus"
- Probiotic.org; "Bifidobacterium Animalis"
- Probiotic.org; "Saccharomyces Boulardii"