Probiotics are the friendly bacteria and microbes that provide many health benefits to humans. Some foods naturally contain probiotics, foods such as yoghurt, pickles, sauerkraut, tempeh (a fermented soy product), miso and Kefir (a milk based drink). Foods such as ice cream, juices or drinks can be fortified with live strains of probiotic bacteria as well.

 Immune-friendly bacteria

 There are many bacteria that are considered as “probiotics”. Some of the common ones associated particularly with gut health include Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium infantis. These strains are usually given to correct the imbalance in the gut bacterial composition following a long course of antibiotics. Antibiotics destroy harmful pathogens in the gut but can also kill the friendly bacteria.

Research has also shown the impact of probiotics on the immune system. The strains of bacteria associated with immunity are

• Lactobacillus reuteri
• Lactobacillus casei
• Bifidobacterium lactis
• Lactobacillus rhamnosus
• Bifidobacterium lactis 

How do probiotics improve immunity?

The immune system in humans is comprised of white blood cells, also called macrophages and lymphocytes, that target intruders such as viruses, germs or toxins. Lowered immune response can increase the frequency and incidences of catching infections such as cold, influenza, gastrointestinal infections and others.

Probiotics stimulate the production of macrophages, lymphocytes, and natural killer (NK) cells that are the first line of defence against infections.

A review of clinical trials found that probiotics step up the number of immunoglobulins (IgA) that act as natural antibodies to harmful germs. Probiotics given in the form of yoghurt or specially cultured milk can strengthen the immune system in the gut by increasing the number of IgA(+) cells according to this review.

 An earlier study involved giving probiotic supplements to 479 adults for three months. While some received only minerals and vitamins, the study group received minerals, vitamins along with probiotics. Researchers found reduced incidence and severity of cold in those who received probiotics.

 A 2014 study published in the Journal of Science and Medicine in Sport involved giving probiotic supplements to rugby players for four weeks. The researchers found those who took probiotics experienced fewer incidences of respiratory or gastrointestinal infections. Out of the 30 participants in the study who received probiotics, 14 players did not experience any infection during the study period.

Out of the thirty participants who were given a placebo, only six of them did not experience any infections during the four-week study period. The researchers also found that probiotics reduced the severity and duration of infections as well.

Disclaimer: The health information published on this web page is solely intended for educational purposes. VitaminsOnly strongly recommends to consult health care professionals for any questions concerning your health.