Bacteria die out over time. Some supplements list the potency when they were manufactured (before they rode in a truck, sat on the shelf at the grocery store, or hung out in the kitchen cupboard for a few months). In this case, there could be dramatically fewer viable bacteria by the time you consume them than when they were first encapsulated, and good bacteria are no good to you dead.
Most bacteria are included through the fermentation process. Fermentation helps extend the shelf life of perishable foods. It is a slow decomposition process of organic substances induced by microorganisms or enzymes that essentially convert carbohydrates to alcohols or organic acids. The lactic acid supplies the bacteria that then add the health benefits to the food. You can purchase foods that are fermented or ferment them yourself.
Probiotics have become buzzy in recent years: Celebrities including Lauren Conrad and Anna Paquin have been spotted carrying bottles of kombucha, a probiotic-containing fermented tea, and the probiotics market has been growing rapidly as more people pursue better health by taking probiotic supplements. Prebiotics are attracting notice too, but you may still be unsure of what exactly prebiotics and probiotics are. Here's what you need to know about them to decide whether taking supplements is right for you.
Third-party testing: Lastly, it's important to remember that probiotics are an unregulated supplement. "Find out whether there is third-party data verifying the potency, purity, and effectiveness of the product," suggests Dena Norton, a registered dietitian and holistic nutrition coach. "Remember that dietary supplements aren't regulated, so you can't necessarily just trust the claims on the label." Check out AEProbio, a site that has compiled research on specific brands of probiotics available in the U.S., recommends Scarlata, and an NSF seal is always a good marker to look for.
L. Casei also made headlines when a study found it beneficial in relieving anxiety. The randomized, double-blind, placebo-controlled pilot study found supplementation with 24 billion units of the L. Casei strain Shirota led to a rise in probiotics Lactobacillus and Bifidobacterium, as well as a significant decrease in symptoms of anxiety and depression [2].

If that’s the case, I recommend steering clear. They either don’t want you to know that they’re using a poorly-researched strain of probiotics or they’re simply ignorant to the fact that the strain of probiotic really matters and determines the benefit that you’ll receive as the consumer. I usually want to give these companies the benefit of the doubt, but honestly, if you’re making a probiotic supplement you should know this stuff is important.

Then, study participants were divided into one group that consumed a standard probiotic strain available in commercial supplements and a control group that was given a placebo. After two months of treatment, the researchers found that some people were so-called “resisters” who expelled the gut microbiomes in probiotics; others were identified as “persisters” who successfully colonized the generic probiotic strains in their GI tracts.
However, these quality of life improvements are varied, and some improvements are quite mild. Sample group, types of allergies, symptoms, and results are across a broad spectrum. For example, numerous studies have shown that allergic rhinitis responses to the household dust mite decrease significantly in adults and children when probiotics were used. However, people allergic to birch pollen saw neither a decrease in general allergic responses to birch pollen or to apple food.
Today, most of the Japanese population begins the day with a warm bowl of miso soup, believed to stimulate the digestive system and energize the body. Made from fermented soybeans, rice or barley, adding a tablespoon of miso to some hot water makes an excellent, quick, probiotic-rich soup. The fermentation process can take anywhere from a few days to a couple of years to complete, and the end result is a red, white or dark brown paste with a buttery texture.
Because of the way bacteria spread from the rectum to the vagina and urinary tract in women, probiotics have been a proposed remedy for urinary tract infection (UTI) in women. A 2012 review confirmed that probiotics seem to be effective in preventing recurrent UTIs, but more research is required before a determination can be made. The healthy strains of bacteria that help achieve this are also somewhat less common, which means proper treatment could be logistically complicated.

The research also showed that while probiotics colonised the gastrointestinal tract of some people, the gut microbiome of others just expelled them. There was no way of telling from their stool sample which category people fell into. “Some people accept probiotics in their gut, while others just pass them from one end to the other,” says Elinav. They found that the probiotic colonisation patterns were highly dependent on the individual. That tells us that the concept that everyone can benefit from a universal probiotic bought from the supermarket is empirically wrong, he says. 

We started our search with the most popular products from major supplement retailers like Amazon,, GNC, and Whole Foods. That gave us over 200 supplements. With so many options, we then narrowed our search to 70 probiotics whose purity, potency, and projected efficacy have been vetted by an independent lab like ConsumerLab, Labdoor or the National Science Foundation (NSF). Those labs test — among other things — supplements’ actual composition against labels, verifying ingredient lists are truthful and that contaminants aren’t present. Because supplement claims aren’t regulated by the Food and Drug Administration (FDA), we wanted to make sure someone was testing whether they worked as described.
Cleaning up your diet to remove things that bother you and to add nutrients you and your microbiota need, physical activity to reduce stress and increase feel-good neurotransmitters, mindfulness to discover how your thoughts affect your feelings, and daily consumption of probiotic pills and foods are easy ways to improve your mental health outlook.