Probiotics may help support our immune system

Active lifestyle and immune health

The immune system is critical for supporting our health, such as by defending against colds and flu-like sickness 

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Respiratory and flu-like sickness 

Respiratory and flu-like sickness includes symptoms such as a fever of at least 100°F (37.8°C) and a cough or sore throat. On average, 33 million Americans suffer with symptoms of flu-like sickness each year.6 Respiratory and flu-like sickness can place a large burden on families and societies due to the costs associated with doctor consultations, medicine prescriptions and loss of workplace productivity.

Effective treatments are not available for most respiratory and flu-like sicknesses; therefore, we must find approaches that support and promote our immune system’s natural defenses. Supplementing with probiotics may be one way to help. Numerous well designed studies suggest that certain probiotics may play a key role in supporting and maintaining a healthy immune system.1, 2, 3, 4, 5, 8, 9, 10 

Probiotics may help a healthy immune system

The L. CASEI 431®, BB-12® and LGG® strains have all been studied in high-quality clinical studies. In children and adults, supplementing with these strains has been associated with a promotion of the immune system and may lower incidence of respiratory and flu-like sickness.1, 2, 3, 4, 5, 8, 9, 10

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But how do we know how strong our immune system is? 

Several clinical studies exists looking at incidence and severity of respiratory tract symptoms and flu-like sickness following probiotic intake for variable periods of time. Another way that studies investigate how well the immune system is working is by giving healthy participants a vaccine that contains a foreign substance, i.e. it is naturally occurring, but not normally found in our body.

These vaccines challenge the immune system, forcing us to fight back. In healthy people, the body will respond by producing specific proteins that fight that particular vaccine challenge. These proteins are called antibodies and how many of these specific antibodies the body produces in response to the vaccine is how we determine how strong our immune system is. The more antibodies we produce in response to a vaccine challenge, the stronger our immune system is thought to be. 

Studies suggest that LGG® may help promote the immune system and may help reduce the incidence of flu-like symptoms

A study of healthy adults investigated how supplementing with the LGG® strain affected the number of antibodies the body produced in response to a vaccine challenge.9 Compared to taking placebo, 29% more participants who took LGG® produced a number of specific antibodies that is associated with increased immune system function. This suggests that the LGG® strain may help promote immune responses by increasing the number of antibodies the body makes to fight against foreign invaders.9  

In another study, children who consumed the LGG® probiotic strain for three months had a significant reduction in the incidence of flu-like sickness.1 The length of time that children experienced symptoms was also reduced, and they had significantly fewer days away from daycare due to illness, compared to the placebo group.1 Similarly, children who consumed LGG® for the length of a hospital stay had a significantly lower incidence of digestive system illness and flu-like sickness.10  

Active seniors immune health and probiotics

Studies suggest that BB-12® may help support the immune system and reduces the incidence of certain types of illness 

Another high-quality study investigated the effect of consuming the BB-12® probiotic strain for two weeks before a vaccine challenge, and for four weeks after.2 The group supplementing with the BB-12® strain had a significant increase in specific antibodies, compared to the placebo group. This suggests that the BB-12® strain may promote immune system function by inducing a significant response to an immune system challenge.2

 When consumed together, the LGG® and BB-12® strains have been associated with a lower number of days with flu-like symptoms.5 In a 12-week study, college students who were given the LGG® and BB-12® strains had 33% fewer days with symptoms and rated their symptoms as significantly less severe, compared to those receiving placebo.5  

Antibodies are proteins that help support our health and fight against illness 

L. CASEI 431® may help promote good health

Several studies have associated the L. CASEI 431® probiotic strain with a healthier immune system response to vaccine challenges. Three high-quality studies administered the L. CASEI 431® strain to healthy adults prior to a vaccine challenge. In all three studies, the group supplemented with the L. CASEI 431® probiotic strain had an increase in specific antibodies associated with the vaccine challenge compared to the placebo group.2, 3, 4 

In a large study, 1104 volunteers received the L. CASEI 431® strain or placebo for 42 days. In those who received L. CASEI 431®, the duration of flu-like illness was significantly reduced compared to placebo.8

LGG®, L. CASEI® and BB-12® may play an important role in how the immune system supports our health

These high-quality clinical studies have associated the LGG®, L. CASEI® and BB-12® probiotic strains with a promotion of the immune system and support the way it responds when confronted with an immune challenge that could affect our health. Additionally, clinical studies show that the probiotic strains may be associated with a reduced incidence, risk, duration and severity of respiratory and flu-like sickness.  

Read what to look for when choosing a probiotic

L. CASEI®, LGG® and BB-12® are registered trademarks of Chr. Hansen A/S. 

The article is provided for informational purposes regarding probiotics and is not meant to suggest that any substance referenced in the article is intended to diagnose, cure, mitigate, treat, or prevent any disease.  
Lactobacillus paracasei, L. CASEI 431®

The probiotic strain Lactobacillus paracasei, L. CASEI 431® has demonstrated improvements to immune health in high-quality, human clinical studies.

L. CASEI 431® is a registered trademark of Chr. Hansen A/S

L.Casei icon
Lactobacillus rhamnosus, LGG®

Lactobacillus rhamnosus, LGG® is the world’s most documented probiotic strain. The LGG® strain has proven benefits across all ages and numerous health areas, including gastrointestinal, immune and oral health.

LGG® is a registered trademark of Chr. Hansen A/S

LGG icon
Bifidobacterium, BB-12® 

The probiotic strain Bifidobacterium, BB-12® is the world’s most documented probiotic bifidobacterium. It has been extensively studied and has been associated with improved outcomes across various health areas.

BB-12® is a registered trademark of Chr. Hansen A/S

BB-12 consumer logo TM

References Open Close

1. Hojsak I, et al. Lactobacillus GG in the prevention of gastrointestinal and respiratory tract infections in children who attend day care centers: a randomized, double-blind, placebo-controlled trial. Clin Nutr. 2010;29(3):312-6. (PubMed)
2. Rizzardini G, et al. Evaluation of the immune benefits of two probiotic strains Bifidobacterium animalis ssp. lactis, BB-12® and Lactobacillus paracasei ssp. paracasei, L. casei 431® in an influenza vaccination model: a randomised, double-blind, placebo-controlled study. Br J Nutr. 2012;107(6):876-84. (PubMed)
3. Trachootham D, et al. Drinking fermented milk containing Lactobacillus paracasei 431 (IMULUS) improves immune response against H1N1 and cross-reactive H3N2 viruses after influenza vaccination: A pilot randomized triple-blinded placebo controlled trial. J Funct Foods. 2017;33:1-10. (Source)
4. de Vrese M, et al. Probiotic bacteria stimulate virus-specific neutralizing antibodies following a booster polio vaccination. Eur J Nutr. 2005;44(7):406-13. (PubMed)
5. Smith TJ, et al. Effect of Lactobacillus rhamnosus LGG® and Bifidobacterium animalis ssp. lactis BB-12® on health-related quality of life in college students affected by upper respiratory infections. The British journal of nutrition. 2013;109(11):1999-2007. (PubMed)
6. Biggerstaff M, et al. Systematic Assessment of Multiple Routine and Near Real-Time Indicators to Classify the Severity of Influenza Seasons and Pandemics in the United States, 2003-2004 Through 2015-2016. Am J Epidemiol. 2018;187(5):1040-50. (PubMed)
7. Putri WCWS, et al. Economic burden of seasonal influenza in the United States. Vaccine. 2018;36(27):3960-6. (PubMed)
8. Jespersen L, et al. Effect of Lactobacillus paracasei subsp. paracasei, L. casei 431 on immune response to influenza vaccination and upper respiratory tract infections in healthy adult volunteers: a randomized, double-blind, placebo-controlled, parallel-group study. Am J Clin Nutr. 2015;101(6):1188-96. (PubMed)
9. Davidson LE, et al. Lactobacillus GG as an immune adjuvant for live-attenuated influenza vaccine in healthy adults: a randomized double-blind placebo-controlled trial. Eur J Clin Nutr. 2011;65(4):501-7. (PubMed)
10. Hojsak I, et al. Lactobacillus GG in the prevention of nosocomial gastrointestinal and respiratory tract infections. Pediatrics. 2010;125(5):e1171-7. (PubMed)

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