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Probiotics Guide – Everything You Ever Wanted to Know

You may have noticed that the wellness community has been raving over probiotics in recent years. It’s not that we just realized that taking care of your gut is important, it’s that we’re learning that the state of your gut affects the state of everything else, even the way you feel. In fact, we’re all made up of about 100 trillion bacteria that outnumber human cells by 10 to 1.1,2 It’s no wonder that having an imbalance of good vs. bad bacteria can influence just about anything.

Let’s dive deeper into what probiotics actually are and why you need to ensure you have enough every day.

What Is the Human Microbiome?

In order to truly grasp why probiotics are so important to health, you need to understand the human microbiome.

The microbiome is an ecosystem containing many types of bacteria and other substances, such as fungi and antimicrobial peptides. The mouth, skin, and gut each possess their own microbiome, but the majority of the bacteria reside inside the gut (also known as the gastrointestinal or GI tract). Even more specifically, most of them live within the large intestine.

To be clear, all bacteria are not created equal. Healthy individuals are made up of both “good” bacteria (a.k.a. probiotics) and “bad” bacteria, with the ideal balance being about 85 percent “good” and 15 percent “bad.” 3

The overall idea is to maintain this balance by consuming probiotics, especially because modern lifestyle factors easily deplete our population of healthy bacteria. Activities like smoking, drinking, medications (especially antibiotics), and poor diet, as well as environmental factors like pollution all contribute to tipping the scales of your microbiome’s balance in favor of bad bacteria.4,5 In fact, unless you’re living a life completely devoid of toxins, which are prevalent in modern society, chances are, your gut microbiome can use some extra probiotics.

Also note that no one is born with a microbiome, because the womb is sterile. Through contact with the mother, including vaginal delivery, the environment, and food the baby consumes (starting with breast milk), every human being’s microbiome is formed upon birth. So, the balance of bacteria is influenced as soon as you enter the world!

Possible Effects of Gut Microbiome Imbalance

According to the American Nutrition Association, any unbalanced gut microbiome can lead to one or more of the following symptoms 6:

  • Fatigue
  • Poor memory or feeling spacey
  • Insomnia and hypersomnia
  • Anxiety
  • Depression
  • Mood swings
  • Muscle and joint aches and pains
  • Alcohol intolerance
  • Itching
  • Frequent urination
  • Skin rash
  • Palpitations
  • Gas or bloating
  • Diarrhea or Constipation
  • Body odors and bad breath
  • Eczema or psoriasis
  • Frequent colds

On an even more serious level, a microbial imbalance may potentially contribute to chronic gut inflammation, chronic fatigue, and skin conditions.

Considering the negative effects that bad bacteria can have on various parts of the body and its many systems, there have been countless studies, and more are underway, that look into how probiotics can prevent or counter the abovementioned conditions. Below are a few promising studies (although this list is certainly not comprehensive):

  • Immunity: Studies have shown that probiotics can help the body regulate its immune response.8,9 (Note: many experts claim 70-80 percent of the immune system lies in the gut, so this finding is not entirely surprising.)
  • GI disorders: A study found probiotics to be “useful in the prevention or treatment of several gastrointestinal disorders.” This includes diarrhea. There is also evidence that probiotics can help with irritable bowel syndrome.10
  • Mental health issues: A study found that probiotics may contribute to changing the neurochemistry of the brain, helping with mood disorders like anxiety and depression.11
  • Cholesterol: Research has shown that specific strains of bacteria can help reduce levels of LDL, or “bad” cholesterol.12

What Are Probiotics?

According to the Food and Agriculture Organization of the United Nations and the World Health Organization, the official definition of probiotics is: “live microorganisms which when administered in adequate amounts confer a health benefit on the host.” (For simplicity, think of “microorganisms” as bacteria, although it can also include other components like fungi and viruses.)

The most common probiotic strains you’ll see on supplement bottles are Lactobacillus and Bifidobacterium, both of which contain many subsets of bacteria types.

The most common ways you can consume probiotics are:

Fermented foods or foods enriched with probiotics, including yogurt (with “live and active” cultures), kimchi, sauerkraut, tempeh, kefir, miso, aged cheese, some beverages like kombucha tea, and some milks.
Supplements in a variety of forms, including capsules and powders.

How Probiotics Work

So, once you consume probiotics, what exactly happens that makes them so good for you? The National Center for Complementary and Integrative Health outlined the various mechanisms in which probiotics can work once they travel to the gut: 14, 15

  • They help sustain the right balance of microbes (remember the 85/15 percent ratio).
  • They produce antimicrobial substances and enzymes that can destroy or halt the growth of bad bacteria.
  • They reinforce the gut’s barrier.
  • They “outcompete undesirable microorganisms”; in other words, they crowd out the bad guys.
  • They help strengthen immune response.
  • How to Choose the Right Probiotic Supplement

    Understandably, you might be overwhelmed with the sheer number of probiotic options you have. Here are the most important factors to consider:

    Number of strains: The human body houses over 500 different strains of probiotics. 16 To optimize colonization of the probiotics you consume, aim for a supplement that offers multiple strains. Many supplements on the market tout seven strains; go for up to 30 to “cover” as much ground as you can.

    High CFU count: The quantity of probiotics themselves matter as much as the number of strains. Aim for a supplement that contains at least 30 billion.

    Effective delivery system: Your stomach acid destroys a lot of substances as food or supplements travel to the gut. Unfortunately, many probiotics don’t even make it to where they need to be to make any difference. Make sure your supplement offers some sort of technology or delivery system, so the live probiotics are protected until they reach your GI tract.

    Effective types of probiotics: Some probiotic strains are studied and known for their health benefits more than others. The most popularly studied strains are the Lactobacillus and Bifidobacterium families.

    Bifidobacterium bifidum: A widely cited study has shown that this strain of probiotic bacteria reduced the number of days that stressed-out students reported having cold or flu symptoms compared to the group that took a placebo.17

    Lactobacillus acidophilus: Research has shown that this probiotic strain can drastically reduce E.coli bacteria and alleviate symptoms of physical digestive duress, including gas and bloating. 18

    Probiotics Guide | Nucific
    How to Slow Down Depletion of Good Bacteria

    In addition to taking a daily probiotic and eating foods containing healthy bacteria, make sure you focus on a plant-based, whole-food diet with lots of fiber, particularly prebiotics. These are indigestible plant fibers that can pave the way for probiotics by helping improve the gut by promoting the growth of good bacteria. 19The good news is, a healthy diet can change the state of your microbiome very quickly, so don’t be discouraged if you’ve been eating sugary junk foods!

    On top of that, find feasible ways to manage stress. A study concluded that stress negatively affects the friendly bacteria in the gut, hindering the gastrointestinal tract’s ability to optimally function. 20 And as with any healthy lifestyle, make sure you get lots of quality sleep and exercise on the regular.

    Finally, try to avoid medication, particularly antibiotics, which have all shown to contribute to gut flora imbalance. 21 In the same vein, don’t overuse antibacterial products found in cleaning supplies and hand washes – they eliminate the good along with the bad.

    The great news is that reinstating the ideal balance of good bacteria requires only a few easy steps – all for major impact. The fastest track to health may simply be found in a capsule and your morning yogurt topped with blueberries.

    For more helpful health news, keep reading:

    5 Ways to Improve Energy Levels (in 10 minutes or less!)

    Dieting and Still Not Losing Weight? (find out why)

    1. Publications, Harvard. “Health Benefits Of Taking Probiotics – Harvard Health”. Harvard Health. N.p., 2005. Web. 13 Mar. 2017.
    2. Probiotics: In Depth”. NCCIH. N.p., 2017. Web. 13 Mar. 2017.
    3. “The Science Of Probiotics | American Nutrition Association”. N.p., 2017. Web. 13 Mar. 2017.
    4.  Reid, Gregor. “Probiotics To Prevent The Need For, And Augment The Use Of, Antibiotics”. N.p., 2006. Web. 13 Mar. 2017.
    5. Conlon, Michael and Anthony Bird. “The Impact Of Diet And Lifestyle On Gut Microbiota And Human Health”. N.p., 2015. Print.
    6. “The Science Of Probiotics | American Nutrition Association”. N.p., 2017. Web. 13 Mar. 2017.
    7. “The Science Of Probiotics | American Nutrition Association”. N.p., 2017. Web. 13 Mar. 2017.
    8. Isolauri, Erika et al. “Probiotics: Effects On Immunity”. N.p., 2001. Web. 13 Mar. 2017.
    9. RJ, Vanderhoof. “Use Of Probiotics In Childhood Gastrointestinal Disorders. – Pubmed – NCBI”. N.p., 1998. Web. 13 Mar. 2017.
    10. Dai, Cong. “Probiotics And Irritable Bowel Syndrome”. N.p., 2013. Print.
    11. “Probiotics: Health Benefits, Facts, Research”. Medical News Today. N.p., 2015. Web. 13 Mar. 2017.
    12. “‘Bad’ And Total Cholesterol Reduced By Daily Doses Of A New Probiotic”. Medical News Today. N.p., 2012. Web. 13 Mar. 2017.
    13.  Hill, Colin et al. “Expert Consensus Document: The International Scientific Association For Probiotics And Prebiotics Consensus Statement On The Scope And Appropriate Use Of The Term Probiotic”. N.p., 2017. Print.
    14.  “Probiotics: In Depth”. NCCIH. N.p., 2017. Web. 13 Mar. 2017.
    15.  “Probiotics”. Cleveland Clinic. N.p., 2017. Web. 13 Mar. 2017.
    16. Publications, Harvard. “Health Benefits Of Taking Probiotics – Harvard Health”. Harvard Health. N.p., 2005. Web. 13 Mar. 2017.
    17.  Langkamp-Henken B, et al. “Bifidobacterium Bifidum R0071 Results In A Greater Proportion Of Healthy Days And A Lower Percentage Of Academically Stressed Students Reporting A … – Pubmed – NCBI”. N.p., 2015. Web. 13 Mar. 2017.
    18. SE, Anderson. “Effect Of Fermented Milk (Yogurt) Containing Lactobacillus Acidophilus L1 On Serum Cholesterol In Hypercholesterolemic Humans. – Pubmed – NCBI”. N.p., 1999. Web. 13 Mar. 2017.
    19.  Moschen, Alexander R., Verena Wieser, and Herbert Tilg. “Dietary Factors: Major Regulators Of The Gut’s Microbiota”. N.p., 2012. Print.
    20. Konturek PC, et al. “Stress And The Gut: Pathophysiology, Clinical Consequences, Diagnostic Approach And Treatment Options. – Pubmed – NCBI”. N.p., 2011. Web. 13 Mar. 2017.
    21. Whiteman, Honor. “Beer, Chocolate Intake Among Factors That Influence The Gut Microbiome”. Medical News Today. N.p., 2016. Web. 13 Mar. 2017.

About the Author

Dr. Amy Lee

Dr. Amy Lee has board certifications in internal medicine, physician nutrition and obesity medicine specialty. She practices internal medicine with a heavy emphasis on nutrition, wellness and weight management. Her Clinical nutrition fellowship training at UCLA has allowed her to incorporate realistic lifestyle modification in all her medicine patients.