You’ve probably heard of probiotics and live cultures, which are typically marketed on yogurt packages as being good for overall health and well-being – and this is 100% true! But did you know that probiotics can be obtained from other delicious, wholesome foods? And although the main area of action is in the gut, regular consumption of probiotics offers health benefits that go beyond the digestive system.

In today’s post, you’ll learn about:

  • What probiotics are
  • 5 health benefits of probiotics
  • 7 fantastic probiotic food sources

What are Probiotics?

The gastrointestinal (GI) system is filled with numerous colonies of bacteria, some of which can be harmful while others are essential to health and well-being. Probiotics are living microscopic organisms that offer health benefits when consumed1. In other words, they are healthy, good bacteria. There are numerous probiotic strains that exist, and each offers a variety of different health benefits. The most common microorganisms come from the Lactobacillus and Bifidobacterium families. Other strains of probiotics include Enteroccocus, Streptococcus, and Escherichia1.

Health Benefits of Probiotics

When the natural balance of intestinal microflora is disturbed, pathogenic bacteria (i.e., the bad guys) are able to overpopulate and “take over” the GI tract2. This results in the development of a number of GI disorders and other ailments in the body, such as Irritable Bowel Syndrome (IBS), Crohn’s disease, bloating, allergies, urinary tract infections, and an overall weakened immune system.

Regularly consuming foods that contain probiotics is what helps restore the populations of healthy microorganisms in the gut. And this presence of good bacteria is an important factor in relieving and preventing the symptoms/illnesses mentioned above4.

Probiotics are believed to have a number of mechanisms of action in order to confer their health benefits. This includes:

  • Modifying the acidity of the GI tract, making it an unlivable condition for pathogenic bacteria2,3
  • Producing antimicrobial compounds that ward off the bad bacteria3
  • Displacing pathogenic bacteria from “binding sites” along the GI tract, and competing against them for nutrients and growth factors3

So what health benefits do probiotics offer us?

1) Better digestion

Proper digestion is important to be able to absorb all of the nutrients that food has to offer. And since nutrient absorption (and some digestion) occurs in the intestinal tract, it’s important that this environment is filled with the good bacteria that will help the process along the way, rather than the bad bacteria that will hinder nutrients from entering circulation.

When problems and infections occur in the digestive tract, it means that food isn’t getting properly broken down and nutrients aren’t getting fully absorbed. And a big part of this problem is due to the lack of good bacteria to keep a healthy and happy environment in the intestines. The consumption of probiotics has been shown to be effective in treating conditions such as IBS, inflammatory bowel disease, diarrhea, H. pylori infections, and bacterial overgrowth5,6. Some probiotic bacteria also help with lactose digestion and therefore offer relief to the symptoms of lactose intolerance7, 8, 9.

2) An enhanced immune system

The strength of the immune system is largely dependent on the health of the gut and digestive system10. Therefore it comes as no surprise that probiotics are the key to optimal immune functioning!

One of the ways that probiotics help strengthen immunity is through the regulation of inflammation responses by balancing the expression of pro- and anti-inflammatory cytokines11, 13.

Another way that healthy microflora boost the immune system is by increasing the number of immunoglobulin A (IgA)-secreting cells in the intestinal system4, 11, 13. Immunoglobulin A is an antibody that protects the body against bacteria and other foreign material, and is mainly produced by cells in the intestinal mucosa14.

Probiotics also create a gut defence barrier and control intestinal permeability – that is, what’s allowed to get absorbed into the bloodstream and what needs to get eliminated12, 13. In this way, the good bacteria prevent against intestinal infections.

Controlling intestinal permeability also prevents larger, undigested food particles from getting absorbed into the bloodstream, and triggering an immune reaction. The body is built to recognize the various nutrients and breakdown products that get absorbed during digestion. However, if a larger, undigested food particle gets absorbed, the body doesn’t recognize it as food but instead as a “foreign” particle, and therefore triggers an immune reaction, also known as an allergic response. And this is just part of the story behind allergies, which leads to the next point.

3) Help overcome allergies

The consumption of probiotics correlates with clinical improvement in allergic symptoms15, 16.

Allergies are abnormal immune responses. So the beneficial effect that probiotics have on the immune system (discussed in the previous point) naturally results in a therapeutic effect on allergic rhinitis, eczema, atopic dermatitis, and food-related allergies16.

When it comes to the mechanisms of action, the involvement of probiotics in controlling hypersensitivity responses is not yet fully understood16. However, maintaining the integrity of the intestinal barrier and blocking large particles from getting absorbed, both contribute to the therapeutic effects of probiotics on allergies and the immune system17.

4) Aid with weight loss

Many factors influence fat storage and the body weight of an individual. Lack of exercise and unhealthy eating habits are obvious, however there is also stress and underlying biochemical factors that may be contributing to the problem, amongst others.

One such underlying biochemical aspect is lack of short-chain fatty acid production and low grade inflammation. These factors influence metabolism, which then affects body weight18.

A fatty acid, in chemistry terms, is a carboxylic acid (carbon, oxygen, and hydrogen structure) with a chain of carbon atoms. These compounds are an important source of energy for cells and they are categorized by their chain length. The “short-chain” fatty acids have a chain length of no more than 6 carbon atoms (you can read more about fatty acids here).

The “good guy” intestinal microflora are responsible for producing short-chain fatty acids from dietary fibre and have a beneficial effect on energy metabolism and body weight management21.

As we recall, the other biochemical factor associated with fat storage and weight management is low grade inflammation. And as we discussed earlier, probiotics help control inflammatory responses through cytokine regulation.

Additionally, studies have shown that various probiotic strains may help with weight loss by reducing adiposity and regulating leptin (the “satiety hormone”) levels18, 19, 20.

5) Prevent urogenital infections

Similar to the intestines, a woman’s urogenital area contains beneficial bacteria that are important in maintaining a healthy environment. An imbalance in good vs. bad bacteria can lead to urinary tract infections (UTIs), vaginal bacteriosis, and yeast infections22. However when there is a healthy environment of probiotic bacteria, these urogenital infections can be prevented23, 24, 25.

7 Probiotic Food Sources

Convinced to add some more probiotics into your life? Fermented foods are one of the best sources of live and active cultures of good bacteria. Try one (or all!) of the following foods for your daily dose of probiotics.

  • kefir
  • yogurt
  • sauerkraut
  • kimchi
  • miso soup
  • tempeh
  • kombucha tea

What’s your favourite probiotic food source? Let me know in the comments below!

 
 

References

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[3] Parvez S, Malik KA, Ah Kang S, Kim HY. J Appl Microbiol. (2006) Probiotics and their fermented food products are beneficial for health. 100(6):1171-85.

[4] Gupta V, Garg R. (2009) Probiotics. Indian J Med Microbiol. 27(3):202-9.

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[9] de Vrese M, Stegelmann A, Richter B, Fenselau S, Laue C, Schrezenmeir J. (2001) Probiotics–compensation for lactase insufficiency. Am J Clin Nutr. 73(2 Suppl):421S-429S.

[10] Iebba V, Nicoletti M, Schippa S. (2012) Gut microbiota and the immune system: an intimate partnership in health and disease. Int J Immunopathol Pharmacol. 25(4):823-33.

[11] Ashraf R, Shah NP. (2014) Immune system stimulation by probiotic microorganisms. Crit Rev Food Sci Nutr. 54(7):938-56.

[12] Perdigon G, Alvarez S, Rachid M, Agüero G, Gobbato N. (1995) Immune system stimulation by probiotics. J Dairy Sci. 78(7):1597-606.

[13] Isolauri E, Sütas Y, Kankaanpää P, Arvilommi H, Salminen S. (2001) Probiotics: effects on immunity. Am J Clin Nutr. 73(2 Suppl):444S-450S.

[14] Mora JR, Iwata M, Eksteen B, Song SY, Junt T, Senman B, Otipoby KL, Yokota A, Takeuchi H, Ricciardi-Castagnoli P, Rajewsky K, Adams DH, von Andrian UH. (2006) Generation of gut-homing IgA-secreting B cells by intestinal dendritic cells. Science. 314(5802):1157-60.

[15] Ö Özdemir. (2010) Various effects of different probiotic strains in allergic disorders: an update from laboratory and clinical data. Clin Exp Immunol. 160(3): 295–304.

[16] Prakash S, Tomaro-Duchesneau C, Saha S, Rodes L, Kahouli I, Malhotra M. (2014) Probiotics for the prevention and treatment of allergies, with an emphasis on mode of delivery and mechanism of action. Curr Pharm Des. 20(6):1025-37.

[17] Zheng Quan Toh, Anzela Anzela, Mimi L. K. Tang, and Paul V. Licciardi. (2012) Probiotic Therapy as a Novel Approach for Allergic Disease. Front Pharmacol. 3: 171.

[18] Mekkes MC, Weenen TC, Brummer RJ, Claassen E. (2014) The development of probiotic treatment in obesity: a review. Benef Microbes. 5(1):19-28.

[19] Kadooka Y, Sato M, Imaizumi K, Ogawa A, Ikuyama K, Akai Y, Okano M, Kagoshima M, Tsuchida T. (2010) Regulation of abdominal adiposity by probiotics (Lactobacillus gasseri SBT2055) in adults with obese tendencies in a randomized controlled trial. Eur J Clin Nutr. 64(6):636-43.

[20] Zarrati M, Salehi E, Nourijelyani K, Mofid V, Zadeh MJ, Najafi F, Ghaflati Z, Bidad K, Chamari M, Karimi M, Shidfar F. (2014) Effects of probiotic yogurt on fat distribution and gene expression of proinflammatory factors in peripheral blood mononuclear cells in overweight and obese people with or without weight-loss diet. J Am Coll Nutr. 33(6):417-25.

[21] den Besten G, van Eunen K, Groen AK, Venema K, Reijngoud DJ, Bakker BM. (2013) The role of short-chain fatty acids in the interplay between diet, gut microbiota, and host energy metabolism. J Lipid Res. 54(9):2325-40.

[22] Santosh S. Waigankar and Vimal Patel. (2011) Role of probiotics in urogenital healthcare. J Midlife Health. 2(1): 5–10.

[23] Falagas ME, Betsi GI, Tokas T, Athanasiou S. (2006) Probiotics for prevention of recurrent urinary tract infections in women: a review of the evidence from microbiological and clinical studies. Drugs. 66(9):1253-61.

[24] Sarah Cribby, Michelle Taylor, and Gregor Reid. (2008) Vaginal Microbiota and the Use of Probiotics. Interdiscip Perspect Infect Dis. 2008:256490.

[25] Santosh S. Waigankar and Vimal Patel. (2011) Role of probiotics in urogenital healthcare. J Midlife Health. 2(1): 5–10.