Probiotics are living microorganisms that we can take through fermented foods or nutritional supplements.

The importance of probiotics was first described by Nobel laureate Élie Metchnikoff in his book “The Prolongation of Life: Optimistic Studies” in 1907. In the book he described the potential “life-prolonging” properties of lactic probiotic bacteria based on the theory that lactic acid has the ability to prolong life.

Even today we can see that more and more studies show that the balance or imbalance of bacteria in our digestive system is closely linked to our overall health.

It is probiotics that support the health of the intestinal balance and are associated with a lot of health benefits. There exist a lot of studies that describe their positive effect on gastrointestinal tract, improving lactose metabolism, lowering cholesterol and stimulating the immune system.

The key health benefits of probiotics are based on studies

1. Probiotics help to balance the beneficial bacteria in our digestive system

For us, probiotics are a source of “good” bacteria and, if used in sufficient amount and regularly, can help to restore intestinal balance. Conversely, intestinal imbalance means that we have a lot of “bad” bacteria that can be caused by disease, drugs (e.g. antibiotics), unhealthy diet or other negative factors. As a result of their action, various digestive problems, allergies, mental problems or other diseases can occur.

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2. They can reduce the risk of diarrhea

Probiotics also have their effectiveness in alleviating the symptoms of diarrhea and can also serve as a prevention. In one study researchers found out that probiotics reduce the risk of  diarrhea occurrence by up to 42 %.

In 35 studies, it was found out that certain probiotic strains (Lactobacillus rhamnosus, Lactobacillus casei and Saccharomyces boulardii yeast) can shorten the duration of diarrhea by an average of 25 hours. They can also reduce the risk of traveler’s diarrhea by 8 %, diarrhea of other causes – by 57% in children and 26% in adults.

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3. They have a beneficial effect on mental health

A lot of studies confirm that probiotics can help with some mental health disorders. In 15 studies it was confirmed that the use of probiotic strains (Bifidobacterium and Lactobacillus) for 1-2 months had a positive effect on anxiety, depression, autism, etc. This is confirmed by a 6-weeks study that looked at 70 laboratory staff who experienced a positive effect on overall health, stress or depression after taking probiotics.

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4. They help to maintain heart health

Probiotics can protect our heart by lowering the levels of “bad” LDL cholesterol and lowering blood pressure.

This is also confirmed by studies that found out that consuming probiotic yoghurt for 2 – 8 weeks showed a reduction in total cholesterol by 4% and LDL cholesterol by 5%.

Another review of 9 studies indicated that probiotic supplements may lower blood pressure to some extent.

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5. They can help with some allergies and skin problems

Some probiotic strains can act to prevent allergic reactions or alleviate certain allergic symptoms. A great number of clinical studies has confirmed that probiotics can improve the symptoms of atopic eczema, allergic rhinitis and some food allergies, such as milk protein allergy.

There is an interesting study that looked at the children of women who took probiotics during pregnancy. The risk of eczema occurrence in these children was up to 83% lower.

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6. They help with some intestinal diseases

Probiotics have a positive effect on the intestinal microflora, prevent the onset of dysbiosis and the multiplication of pathogenic microorganisms, prevent the development of gastrointestinal infections, regulate intestinal motility and generally have a significant effect on the health of the body.

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Some probiotic strains (Bifidobacterium and Lactobacillus) have also been shown to help with specific inflammatory bowel diseases, such as ulcerative colitis and irritable bowel syndrome.

7. They help to strengthen the immune system and protect against infections

Several studies have confirmed that probiotics have a beneficial effect on our immune system and can promote the production of natural antibodies in the body. In the same way, some probiotic strains have been found to have a beneficial effect on various types of infections, such as:

• A study of 570 children concluded that taking Lactobacilla GG reduced the severity of respiratory illness by 17%
• Another study suggests that the probiotic strain Lactobacillus crispatus may reduce the risk of urinary tract infections (UTIs) in women by 50%

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Source: https://www.healthline.com/nutrition/8-health-benefits-of-probiotics#TOC_TITLE_HDR_1