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  • Writer's pictureLaurenWallace

Probiotics: Top Benefits, Foods and Supplements



By Dr. Josh Axe, DC, DNM, CN

November 5, 2021

Original article and page source found here.


Whether you’re looking to help your immune function, decrease disease risk or simply improve your overall health, probiotics can make a worthy addition to your daily routine.

Not only that, but some people — including billionaire philanthropist Bill Gates — even believe that probiotics could hold the key to ending malnutrition across the globe someday.

What are probiotics? Probiotics are a type of organism that can help boost the amount of beneficial bacteria in your gut. Nestled inside your gut are trillions of these live microorganisms that make up the microbiome.

They are also found in supplements, fermented foods (such as tempeh, natto and miso) and probiotic drinks, such as kombucha.

Different microbes living in your gastrointestinal tract play a role in either promoting health or disease. For example, many of these bacterial cells are considered “good bacteria” and help support immune function, enhance nutrient absorption, and aid in the synthesis of key neurotransmitters and other compounds.

What Are Probiotics?

Probiotics are defined as live bacteria that line your digestive tract that support your body’s ability to absorb nutrients and fight infection.

Did you know that your body contains about the same number of gut bacteria molecules as it does cells for the rest of your body? It’s no wonder then that your gut is so important to your health. Your skin and digestive system alone host about 2,000 different types of bacteria.

The National Center for Complementary and Integrative Health (NCCIH) calls probiotics “live microorganisms (in most cases, bacteria) that are similar to beneficial microorganisms found in the human gut.” The NCCIH makes the point that we often think of bacteria as harmful “germs” — however, probiotic bacteria actually helps the body function properly.

What happens when you start taking probiotics? Probiotics benefits have been proven effective in supporting immune function, reducing inflammation, promoting healthy digestion, managing inflammatory bowel disease, as well as maintaining beautiful skin, especially when combined with prebiotics.

Your “good gut bacteria” is also responsible for:

  • Producing vitamin B12, butyrate and vitamin K2

  • Crowding out bad microbes

  • Enhancing gut mucosal barrier function and preventing the invasion of pathogens in the intestinal epithelium

  • Helping regulate the central nervous system

  • Creating enzymes that destroy harmful microbes

  • Stimulating secretion of IgA and regulatory T cells, which support immune function

Probiotics are in your system from the moment you are born. When a newborn is in the birth canal of the mother during delivery, the baby is exposed to the live bacteria of his or her mother for the first time.

This event starts a chain of events inside the baby’s gastrointestinal tract, and the infant’s GI tract starts to produce good bacteria.

Historically, people had plenty of probiotics in their diets from eating fresh foods from good soil and by fermenting foods to keep them from spoiling.

Today, however, because of refrigeration and agricultural practices, like soaking our foods with chlorine, much of our food contains little to no probiotics in the name of sanitation. Actually, many foods contain dangerous antibiotics that kill off the good bacteria in our bodies.

Health Benefits

1. Improve Digestive Health

The first major benefit of probiotics is as a promoter of good digestive health. A 2019 review explains that probiotic consumption has been shown to improve the immune, gastrointestinal and reproductive health systems in healthy adults.

In fact, according to a meta-analysis of clinical trials:

Probiotics are generally beneficial in treatment and prevention of gastrointestinal diseases… When choosing to use probiotics in the treatment or prevention of gastrointestinal disease, the type of disease and probiotic species (strain) are the most important factors to take into consideration.

Eating foods rich in good bacteria and using probiotic supplements may help provide protection from inflammatory bowel diseases, including ulcerative colitis and Crohn’s disease. The evidence is stronger, however, for an improvement in ulcerative colitis, while Crohn’s disease may not benefit as greatly.

In addition, there is ongoing research studying the role of probiotics in gluten issues, including celiac disease.

Large bodies of evidence suggest that probiotics are also effective against several forms of diarrhea, including antibiotic-associated diarrhea, acute diarrhea, traveler’s diarrhea, infectious diarrhea and other associated diarrhea symptoms. They also help with constipation relief.

Additionally, probiotics have been found in meta-analyses to reduce the pain and severity of irritable bowel syndrome (IBS) symptoms, aid in the eradication of H. pylori and treat pouchitis, a condition that occurs after the surgical removal of the large intestine and rectum. For the most benefits in managing IBS, studies suggest that it’s best to take multi-strain probiotics capsules over a period of at least eight weeks.

2. Help Decrease in Antibiotic Resistance

The World Health Organization considers antibiotic resistance “one of the biggest threats to global health, food security and development today.” Bacteria become resistant to antibiotics due to the overuse of prescription antibiotics, lack of diversity in these medications and improper use of antibiotics.

By using probiotics, it’s possible to help rebuild a poor variety of gut bacteria often seen after a course of taking antibiotics and prevent antibiotic-associated gut issues. In addition, probiotic from supplements and foods may increase the effectiveness of antibiotics and help prevent the bacteria in your body from becoming resistant.

3. May Fight Mental Illness

The “second” brain of the gut has been a major point of research since scientists have discovered the importance of the gut-brain connection. A review in 2015 highlighted the complex interactions between the gut and brain, stating:

[Various gut-brain] interactions seem to influence the pathogenesis of a number of disorders in which inflammation is implicated, such as mood disorder, autism-spectrum disorders, attention-deficit hypersensitivity disorder, multiple sclerosis, and obesity.

The authors discuss the need for “psychobiotics” (probiotics that impact brain function) in handling the development of these conditions. This anti-inflammatory quality is what seems to interest researchers most.

While limited clinical trials focusing on this topic have been conducted in humans, early research suggests that, in animals, supplementing with probiotics may help alleviate symptoms of anxiety by reducing inflammation along this gut-brain connection.

Several rodent studies have shown that consumption of probiotics can prevent increases in certain stress hormones, including ACTH, corticosterone and epinephrine, via the hypothalamic-pituitary-adrenal axis.

Probiotics benefits seem to include a reduction in depression symptoms, according to a 2016 meta-analysis — the first review of its kind. Taking probiotics might also help reduce re-hospitalizations from manic episodes for those with manic depression.

A slightly more surprising result, however, seems to be the way that probiotics may impact some of the symptoms of autism. Autism and gut health have been discussed for some time, as patients with the disorder typically suffer from a large number of digestive issues.

However, based on animal studies, it seems possible that altering the quality of gut bacteria might benefit not only the digestive system, but the abnormal behaviors in autism, too.

In 2016, a case study of a boy with severe autism was reported. While being treated with probiotics for digestive problems, the patient spontaneously improved on the ADOS scale, a diagnostic rating system for people with autism.

The score dropped from 20 down three points to a stable 17, and according to the report, ADOS scores do not “fluctuate spontaneously along time” and are “absolutely stable.”

Because of results like those above, human studies are underway to determine if probiotic treatments may improve not only the GI symptoms seen in autism, but also on “the core deficits of the disorder, on cognitive and language development, and on brain function and connectivity.”

4. Boost Immunity

Both probiotics and prebiotics are continuing topics of research regarding immunity. When used in conjunction, scientists refer to them collectively as synbiotics.

One 2015 review on the subject stated, “We suggest that LAB and Bifidobacteria and novel strains [of probiotics] might be an additional or supplementary therapy and may have potential for preventing wide scope of immunity-related diseases due anti-inflammatory effect.”

Because chronic inflammation is at the root of many diseases and health conditions, the fact that probiotics exert this effect in the gut, where 80 percent of the immune system lies, is crucial. The immune-boosting benefits of probiotics seem to be particularly helpful for the quality of life of seniors.

Research is underway to test whether probiotics can “reduce inflammation and improve gut immune health in HIV-positive individuals” who haven’t yet undergone treatment.

A 2021 review even found the poor prognosis in COVID-19 infections was seen in adults with underlying co-morbidities who had increased gut permeability and reduced gut microbiome diversity. According to the researchers’s findings, “Dietary microbes, including probiotics or selected prebiotics of Chinese origin, had anti-viral effects against other forms of coronavirus, and could positively impact host immune functions during SARS-CoV-2 infection.”

5. Support Healthy Skin

Many avenues of research have examined probiotics benefits for skin, especially in children. Meta-analyses have found that probiotics may be effective in the prevention of pediatric atopic dermatitis and infant eczema.

The integrity of gut bacteria is also connected to the development of acne, although the way this happens is still unclear.