friendly bacteria

What is lactobacillus: why does the body need it?

02 Dec 2021 • 2 min read


“Friendly bacteria” is often a term used in advertising or marketing to give you an idea of how probiotics work in the body.

Lactobacillus is one of those bacteria that is often used in fermented foods like yoghurts and can also be found as lactobacillus supplements1.

It also has many health benefits, including support of your digestive, urinary and genital systems.2

In this article, we’ll cover everything you need to know about lactobacillus and find out just how friendly it is.

What is lactobacillus?

Lactobacillus is a type of bacteria.

There are numerous species of lactobacillus, which are all known as “friendly” bacteria that normally live in your digestive, urinary and genital systems without causing you any trouble.

Most commonly, lactobacillus is used to treat diarrhoea, infectious diarrhoea and diarrhoea linked to the use of antibiotics.3

For some lactobacillus is used to help with digestion. It’s been noted as being particularly useful for helping with:

  • Irritable bowel syndrome (IBS)
  • Colic in young children
  • Inflammation or swelling in the digestive tract
  • Inflammation of the colon

However, more research is needed to clarify just how effective lactobacillus is on these conditions.

What does lactobacillus do in your body?

We have many bacteria and other organisms living in our bodies, lactobacillus is no different.

The job of lactobacillus is to help you break down food, absorb nutrients and use its “friendly” nature to fight off unwanted bacteria that may cause stomach upsets such as diarrhoea.

12 benefits of lactobacillus

The following science-backed benefits4 have been labelled lactobacillus as being possibly effective for:

  1. May help with stomach pain

Research shows that women and children taking lactobacillus may help improve symptoms of stomach pain. 

  1. Could improve hay fever symptoms

It is thought that taking lactobacillus daily for five weeks may improve symptoms for grass pollen allergies, such as hay fever.

It is also considered that a higher dosage can improve itchy eye symptoms over a 12 week period.

  1. Help with symptoms of diarrhoea

Much research into lactobacillus shows that both adults and children who take probiotic products that contain lactobacillus can help prevent diarrhoea caused by taking antibiotics.

Studies show that lactobacillus may reduce the chance of diarrhoea by 60 to 70% when taken within two days of the beginning of treatment.

  1. May help eczema (atopic dermatitis)

Research shows that lactobacillus products can reduce eczema symptoms in infants and children.

It is also considered that lactobacillus may help prevent eczema from developing altogether.

Also, if taken in the last month of pregnancy, mothers may be able to prevent their child from developing eczema if they use lactobacillus.

Although not all strains are proven to work.

  1. Could help those prone to allergies and allergic reactions (atopic disease)

Some research shows that certain strains of lactobacillus may prevent you from developing allergic reactions, such as asthma, runny nose and eczema in infants with a history of this condition.

  1. May support against vaginal bacteria

Research has shown that lactobacillus suppositories and vaginal tablets can help prevent the growth of bacteria in the vagina.

Studies have also found that eating yoghurt or using vaginal capsules that contain lactobacillus may help prevent reoccurring infections.

However, the results of the study found that this will not prevent the overgrowth of bacteria in pregnant women.

  1. May help children with colic

Some research into lactobacillus has found that there may be links to nursing infants who have colic.

Colic is when a child cries a lot without any real known cause5 and lactobacillus is thought to be able to reduce, although this is thought to be dependant on the severity of colic.

  1. Could help with constipation

Studies have found that using lactobacillus probiotics for around four to eight weeks may reduce symptoms of constipation, this includes:

  • Stomach pain
  • Discomfort
  • Bloating
  • Bowel movement
  1. May help with diarrhoea in children

Giving children aged between 1-36 months old lactobacillus can reduce the risk of development diarrhoea.

It is not thought that lactobacillus can reduce the risk of diarrhoea in older adults.

  1. May reduce cholesterol

Taking lactobacillus probiotics may help lower your cholesterol in people with or without high cholesterol.

  1. May help airway infections

Some research indicates that lactobacillus may help prevent airway infections in both children and adults.

Infants and children who are given lactobacillus are at less risk of airway infections. However it is thought that not all strains of lactobacillus seem to work.

For adults, drinking fermented milk or powder that contains lactobacillus might help prevent airway infections and decrease how long symptoms last. However, this does not seem to help prevent infection in older adults.

  1. Could help rheumatoid arthritis

Finally, research into lactobacillus shows that taking a supplement for eight weeks may reduce the swelling of tender joints in women with RA.

However, studies also show that a reduction of symptoms can differ depending on how severe the problem is.

How to get lactobacillus from your diet

As mentioned previously, lactobacillus can be found in yoghurt and other dairy products. It does however also occur naturally in some fermented foods, including5:

  • Kombucha
  • Some cottage cheese
  • Kefir
  • Sauerkraut
  • Miso
  • Tempeh

How to use lactobacillus

You can add lactobacillus to your diet with ease.

One of the most popular ways of doing this is by eating yoghurt or drinking yoghurt drinks.

As mentioned above, you can also add more lactobacillus through dietary supplements.

If you are looking to do this, you should choose a reputable brand and make sure you follow the directions carefully.

What are the side effects of lactobacillus?

If you’re generally healthy and don’t have any underlying health issues. Side effects for taking lactobacillus are generally minimal.7

However, excessive use may result in:

  • Gas
  • Bloating
  • Mild digestive complaints

If you have any serious underlying health concerns, you may consider close monitoring when taking probiotics as they may increase the risk of infections and other, more severe side effects.

Those who are lactose intolerant should also check the packaging before taking lactobacillus supplements as many contain lactose.

If you have any concerns about taking a probiotic, you should contact your GP or speak to a health professional.

Summary of lactobacillus

  • Lactobacillus is a “friendly” bacteria that has many varieties. They live in your digestive, urinary and genital systems.
  • It’s used in your body to help fight off bad bacteria that cause stomach upsets such as diarrhoea.  
  • There are many health benefits, most of which involve stomach upsets and vaginal hygiene. It is most effective in conditions for women and young children.
  • It’s generally safe to use and can be found in dairy products such as yoghurt, or as a supplement.

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The advice in this article is for information only and should not replace medical care. Please check with your GP or healthcare professional before trying any supplements, treatments or remedies. Food supplements must not be used as a substitute for a varied and balanced diet and a healthy lifestyle.

Last updated: 3 December 2021



Author: Bhupesh PanchalSenior Regulatory Affairs Associate

Joined Holland & Barrett: Apr 2019

Masters Degree in Toxicology and BSc Hons in Medical Biochemistry

Bhupesh started his career as a Clinical Toxicologist for Public Health England, advising healthcare professionals all around the country on how to manage clinical cases of adverse exposure to supplements, pharmaceuticals, cosmetics, industrial chemicals and agricultural products.

After 7 years in this role and a further year working as a drug safety officer in the pharmaceutical industry, Bhupesh joined Holland & Barrett as a Senior Regulatory Affairs Associate in 2019.

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