Respiratory tract infections (RTIs) are a common health concern, affecting millions of individuals each year. These infections encompass a wide range of conditions, from the common cold to more severe illnesses like pneumonia and bronchitis.

PROBIOTICS: THE GUT-RESPIRATORY TRACT CONNECTION

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. While traditionally associated with gut health, emerging research suggests that probiotics may have a role in bolstering the immune system, which can extend to respiratory health.

• Modulating the immune response: Probiotics have been shown to enhance the body's immune response, making it better equipped to fend off infections. These beneficial microorganisms interact with the gut-associated lymphoid tissue (GALT) and can influence the systemic immune response.
• Reducing the severity and duration of infections: Some studies indicate that certain probiotic strains, such as Lactobacillus and Bifidobacterium species, may reduce the severity and duration of respiratory infections. Probiotics may help by reducing inflammation and enhancing mucosal defence mechanisms.
• Prevention of upper respiratory tract infections: Research suggests that probiotics may be particularly useful in preventing upper respiratory tract infections, such as the common cold and seasonal flu.

VITAMIN C: AN ANTIOXIDANT POWERHOUSE

Vitamin C, also known as ascorbic acid, is a water-soluble vitamin that has long been associated with immune support. While it is essential for overall health, vitamin C's role in preventing RTIs is of particular interest.

• Antioxidant properties: Vitamin C is a potent antioxidant that helps protect cells from oxidative stress. This can be especially important during infections when the immune system is working overtime.
• Immune system support: Vitamin C supports the production and function of white blood cells, which are crucial components of the immune system. It also helps enhance the body's production of interferons, which play a key role in antiviral defence.
• Reducing severity and duration: Some studies suggest that vitamin C supplements may reduce the severity and duration of respiratory infections, including the common cold.

Probiotic characteristics are not associated with the genus or species of a microorganism, but with few and specially selected strains of a particular species. Recommend probiotic supplements with strains that have demonstrated respiratory health benefits e.g. Lactobacillus rhamnosus GG, Bifidobacterium animalis subsp. lactis BB-12, Bifidobacterium animalis subsp. lactis HN019, Lactobacillus acidophilus NCFM, Lactobacillus paracasei subsp. paracasei DN‐114001, and Lactobacillus plantarum 299v.

COMBINING PROBIOTICS AND VITAMIN C

While probiotics and vitamin C can be beneficial individually, combining them may offer synergistic effects. Probiotics can help modulate the immune response in the gut, while vitamin C provides antioxidant support and immune system enhancement. This combination may be especially helpful for individuals at higher risk of RTIs.

When recommending these supplements, always consider individual needs and preferences, as well as potential interactions with other medications or conditions.

REFERENCES

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