Be a pro on probiotics

There sure is a ton of hype on probiotics these days.

While there is no magic pill for health, probiotics may be a major player in the game. This blog answers all your questions about probiotics: what they are, why they help, and what to look for in a supplement.

You’ll also get some key research findings on how probiotics may benefit certain health conditions. 

Understanding the Microbiome

Did you know that humans are composed mostly of bacteria cells? The bacteria in our bodies outnumbers human cells 10 to 1.

Meet the microbiome, home to up to 2,000 different species of microorganisms and 80% of our immune system. It’s no wonder that an imbalanced microbiome is associated with all kinds of inflammatory diseases and conditions.

The microbiome is the center of the enteric nervous system (the nervous system of the gut), which closely communicates with the brain to demand orders! Who knew bacteria could be controlling our body?!

Keeping the Balance

The ideal balance in the microbiome consists of 85% “good’ bugs and 15% “bad” bugs.

So, what contributes to overgrowth of the “bad” bugs?

  • Refined grains, white sugar and high fructose corn syrup (HFCS) may act as fuel for harmful bacteria. These bacteria ferment certain carbohydrates, causing symptoms like gas, pain, bloating and even constipation and diarrhea. Additionally, eating a lot of refined carbs can cause imbalances like Candida overgrowth.
  • Frequent use of antibiotics. Antibiotics cannot distinguish between beneficial and harmful bacteria. Consequently, they not only combat bad bugs, but the good ones as well, causing an imbalance in the microbiome.
  • Pollution and environmental toxins (pesticides, heavy metals, chemicals, etc.) can kill off beneficial bugs, allowing harmful bugs to prosper.

What are Probiotics?

According to the World Health Organization, probiotics are “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.”

Probiotics can be found in fermented foods like yogurt, kimchi, kefir, sauerkraut, kvass, kombucha, natto and miso. Probiotics can also be found as supplements.

Probiotic Benefits

Some of the benefits of probiotics include:

  • Better immune system health and consequently, less risk of autoimmune dysfunction and inflammation
  • Increased healing of the intestinal lining and relief from functional gut disorders, leaky gut syndrome (LGS) and decreased intestinal permeability
  • Improved digestion and absorption of nutrients
  • Balanced mood
  • Decreased risk of small intestinal bacterial overgrowth (SIBO) and dysbiosis
  • Weight loss and increased glucose and insulin sensitivity

Prebiotics vs. Probiotics

Prebiotics are fibers like inulin, Fructooligosaccharides (FOS), psyllium husk or guar gum that act as beneficial fuel for probiotics in the microbiome. These fibers resist digestion and pass through the digestive tract unphased.

That is, until they reach the large intestine, where they are mostly digested by Bifidobacterium, one of the primary bacteria types in the body. The end products of bacteria digesting prebiotics are called short chain fatty acids (SCFA).

An article published in the British Journal of Nutrition indicates that these compounds reduce the risk of harmful bacterial overgrowth, certain cancers, and functional GI disorders. They also improve immune function, glucose tolerance and insulin sensitivity.

Are different strains of probiotics better for certain health concerns?

Lactobacillus and Bifidobacteria are two of the biggest genuses of bacteria in the gut and are usually found in most probiotic supplements. Genus is the umbrella term for bacteria type, followed by the bug’s species and strain. For instance, L. rhamnosus GG indicates that Lactobacillus is the genus, rhamnosus is the species and GG is the strain.

While most probiotics have beneficial effects, there are some strains that are specifically helpful in treating certain health conditions.

  1. Allergic Rhinitis and the Immune System

  • The Research-

    • Taking probiotics could be one of the best ways to boost the immune systems. This systematic review concluded that the use of beneficial bacteria in immunological conditions like allergic rhinitis is helpful in addition to conventional treatment, though more studies are needed to confirm the findings.
    • Benefits included decreased symptoms, improved quality of life, decreased medication use, or reduced total or antigen specific IgE in the treatment of allergies.
    • Beneficial strains include: Lactobacillus paracasei 33, Lactobacillus casei, Lactobacillus salivarius, Lactobacillus plantarum, Lactobacillus gasseri, Bifidobacterium lactis, and Bifidobacterium longum.
  • The Takeaway –

    • Probiotics may help decrease allergy symptoms, medication use and IgE secretion in the treatment of immune mediated conditions like allergic rhinitis.

2. Obesity

  • The Research-

    • Researchers have determined obese individuals have less diversity in their microflora.
    • They found that high-fat, high-sugar diets lead to decreased bacteria from the bacteroides family and more from the firmicutes family in obese people. This is harmful because Firmicutes extract more sugar from carbohydrates, causing increased fat storage.
    • More studies are needed to determine if an imbalance in the gut flora is causative of or only correlated to obesity. However, research has found that probiotics can be helpful in reducing metabolic inflammatory markers that are often present in obesity. Because those with obesity have a decrease in bifidobacterium, those probiotic strains might be among the most beneficial.
  • The Takeaway-

    • Probiotics may help decrease inflammatory metabolic markers in those with obesity, as well as help repopulate the microbiome with beneficial bacteria.

3. Type 2 Diabetes Mellitus (T2DM)

  • The Research-

    • Type 2 Diabetes Mellitus (T2DM) is a disease characterized by insulin resistance, inflammation and impaired glucose tolerance. One study found decreased fasting plasma glucose levels and C-reactive protein (a marker of inflammation), and increases in glutathione (which quenches oxidative stress and inflammation) in participants that took probiotics for an 8 week period.
    • Beneficial strains include: Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium breve, Bifidobacterium longum, and Streptococcus thermophilus.
  • The Takeaway-

    • Probiotics can help decrease fasting blood glucose and inflammation and increase glutathione (the master antioxidant in the body).

3. Irritable Bowel Syndrome (IBS)-

  • The Research –

    • Research indicates that taking probiotics may be beneficial for those with IBS. This study found reduced symptoms in patients with IBS-C, specifically pain, flatulence and bloating after taking probiotics.
    • Another review, which included all IBS subtypes, indicated that Lactobacilli and Bifidobacterium, but also Streptococcus salivarius, Saccharomyces boulardii and probiotic mixtures such as VSL#3, all led to some improvement in symptoms.
    • Another study found that Saccharomyces cerevisiae was helpful in relieving constipation in those with IBS-C.
    • Overall, beneficial strains include: Lactobacillus acidophilus, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus rhamnosus, Streptococcus salivarius, Saccharomyces boulardii, and Saccharomyces cerevisiae.
  • The Takeaway –

    • Benefits of taking a probiotic for IBS may include decreased pain, bloating, flatulence and constipation.

4. Small Intestinal Bacterial Overgrowth (SIBO)

  • The Research –

    • SIBO is characterized by an overgrowth of bacteria where it doesn’t belong – in the small intestine. These bacteria ferment our food (especially carbohydrates), promote maldigestion and absorption, and cause IBS like symptoms. Evidence suggests that up to 80% of people with IBS also have SIBO.
    • One pilot study suggests that prebiotics and probiotics together may be beneficial alongside conventional treatment (antibiotics and prokinetic agents) for SIBO. While probiotics are still being studied for this condition, chances are that using the probiotic strains that are beneficial for IBS may also help with SIBO.
    • Beneficial strains may include: Lactobacillus acidophilus, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus rhamnosus, Streptococcus salivarius and Saccharomyces boulardii.
  • The Takeaway-

    • While more research is needed on specific beneficial strains for treatment of SIBO, taking a probiotic may help with symptoms that mimic IBS.

5. Depression

  • The Research-

    • Up to 95% of serotonin is produced in the gut. It makes sense then that there is a connection between an imbalanced microbiome and mood disorders.
    • One review suggests that Lactobacillus helveticus, Bifidobacterium longum, Bifidobacterium infantis and Lactobacillus rhamnosus may be particularly helpful in reducing psychological stress and depression.
  • The Takeaway-

    • Taking probiotics may decrease stress and depression by increasing the amount of serotonin produced in the gut.

6. Non-Alcoholic Fatty Liver Disease (NAFLD)/Non-Alcoholic Steatohepatitis (NASH)

  • The Research-

    • This meta-analysis found that the Lactobacillus , Bifidobacterium and Streptococcus strains were all beneficial in the treatment of NAFLD/NASH. Benefits included decreased liver enzymes, total cholesterol and tumor necrosis factor alpha (TNF-) in adults with NAFLD or NASH.
    • Beneficial strains may include: Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus GG and Bifidobacterium Longum
  • The Takeaway-

    • Taking probiotics may benefit those with liver dysfunction by lowering liver enzymes, cholesterol and inflammation.

Probiotic Supplement Buying Guide

Not all probiotic supplements are created equal.

Effective probiotics must survive the length of the intestinal tract, including the acidic environment of the stomach. A good supplement manufacturer ensures that bacterial strains are not destroyed by stomach acid by using acid resistant capsules or a freeze drying process.

Additionally, follow these guidelines to ensure you get a high quality probiotic product:

  • Contains live and active cultures –
    • Look for this phrasing on the label instead of “made with active cultures.” Probiotics made with active cultures may undergo heat processing after fermentation to increase shelf life. This can decrease the number of active bacteria present.
    • Do not purchase a product that claims potency only at the time of manufacturing, as this likely indicates the amount of bacteria advertised is no longer viable.
  • Contains at least 1 billion CFU (colony forming units) –
    • Dosing can depend on the probiotic strain as well as the intended theraputic effect
    • Check the ingredients label and make sure to take the recommended dose, typically with a meal for optimal impact.
  • Free of allergens –

    • Always make sure that your probiotic supplement does not contain harmful fillers or substances that cause allergies or sensitivities. These might include dairy, gluten, corn or soy.
    • For those with SIBO or IBS, prebiotics in foods can make symptoms worse. However, taking a symbiotic (prebiotics and probiotics together) is not typically problematic due to the small dose of prebiotics in the formulation.
    • For those with candida overgrowth or a mold allergy, taking yeast strains like Saccharomyces boulardii should not exacerbate the issue. In fact, research shows that S. boulardii may actually help control candida overgrowth.
  • Expiration date and batch number –

    • High quality probiotic supplements should contain the expiration date and the batch number printed on the label. This information guarantees live probiotics through the point of expiration based on real time data.  
  • Refrigerated or Room Temperature?-

    • Although there is little data available on whether refrigerated or shelf stable probiotics are best, it is known that high temperatures and moisture destroy bacteria. 
    • Either way, make sure you aren’t purchasing more than a two month supply at one time. The longer a probiotic sits around, the more time it may potentially encounter harmful elements. Some degradation is bound to occur by the time the product reaches the consumer. Therefore, a quality manufacturer provides significant overages of CFUs at the time of production to make sure their product still contains the amount of bacteria it advertises.

Are You a Pro on Probiotics?

You now know that the microbiome and the effect of beneficial bacteria on health is a highly researched topic. However, it’s becoming increasingly clear that feeding and maintaining friendly bugs is key to promoting health and preventing disease. Remember, most disease stems from the gut, so keeping the good bugs happy is a great way to keep the body healthy and resilient.


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