Lactobacillus rhamnosus, LGG® is the most scientifically researched type of Lactobacillus bacteria worldwide. With over 2,000 scientific publications - including over 300 human studies across all life stages, from newborns to older adults - LGG has gained global recognition from various expert panels and organisations, including the World Gastroenterology Organisation (WGO) and leading paediatric organisations such as the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN).
First patented & isolated in 1985 from a human gut sample, LGG® has attracted major scientific attention - and for good reason. Impressively resilient, it has the ability to survive the highly acidic stomach environment and thrive in the rest of the gut. Once inside, it has been shown to protect our gut through many mechanisms, from attaching to the lining of the gut and competing with ‘unfriendly’ microbes, to reducing inflammation, producing antimicrobial by-products and influencing our gut immune responses. But what does that actually mean for your health goals? In this blog we’ll dive into what the science has taught us so far.
Scientifically proven applications:
Over 40 years of extensive scientific research on LGG® supports its use in the following:
Antibiotic-associated diarrhoea (AAD):
If you’ve taken antibiotics, you may be familiar with the not-so-fun side effects that can tag along - like diarrhoea, bloating, or that weird off-taste in your mouth. The good news is, there’s strong scientific evidence that Lactobacillus rhamnosus, LGG® can help reduce those uncomfortable symptoms.
Multiple gold-standard clinical studies have shown that LGG® supplementation can significantly ease the harsh digestive side effects often caused by antibiotics. Here’s what the research shows, compared to a placebo (a fake intervention):
● Less diarrhoea: LGG® significantly reduces the risk of developing AAD in people taking a combination of antibiotics for the treatment for H. pylori infection.
● Less bloating: Bloating symptoms were more than halved in those with AAD.
● Improved taste: LGG® reduced taste changes by 75%.
It works for children, too. A study of 202 children aged 6 months to 10 years found that supplementation with LGG® vs. placebo reduced the risk of developing diarrhoea in children treated with oral antibiotics for common childhood infections.
Taking LGG® alongside antibiotics isn’t just backed by these studies – it’s also recommended by leading health authorities, including the World Gastroenterology Organisation (WGO) and ESPGHAN. Their clinical guidelines support the use of LGG® to help reduce the risk of digestive side effects linked to antibiotics.
Here’s how to use LGG® effectively: Start taking it at the beginning of your antibiotics course and continue for one week after finishing the course. The recommended dose is 10 billion LGG® twice a day, as per the WGO guidelines on probiotics.
You can read more about AAD here.
Infectious diarrhoea in children:
A large review of studies involving almost 1,000 children showed that those supplemented with LGG®, compared to a placebo, had a:
● Shorter duration of diarrhoea by approximately one day
● Reduced risk (by half) of diarrhoea lasting more than 3-4 days
● Reduced time spent in hospital by nearly a day, especially in those with rotavirus.
The WGO and ESPGHAN guidelines both recommend LGG® for infectious diarrhoea (also called acute gastroenteritis) in children, suggesting a dose of ≥10 billion LGG® per day.
Prevention of hospital-acquired diarrhoea:
According to ESPGHAN guidelines, LGG® may help reduce the risk of hospital-acquired diarrhoea in children – e.g. diarrhoea you catch from a stay in hospital. The recommendation is to supplement with at least 1 billion LGG® per day, for the duration of their hospital stay. This is based on a large review of LGG® supplementation studies, including more than 1,000 hospitalised children, which found that LGG® (compared to a placebo) reduced the risk of:
● Developing hospital-acquired diarrhoea by >60%
● Rotavirus infection with symptoms by 50%.
Preventing upper respiratory infections:
Did you know that 70% of your immune system lives in your gut? That’s why your gut microbiome plays a crucial role in keeping infections at bay. In fact, research shows that supporting your gut health can have a major impact on your overall immunity, too.
Upper respiratory tract infections (such as colds and flu), are the leading cause of acute illness wordwide, putting a heavy burden on healthcare services. With adults catching a cold on average 2-3 times a year, and kids 5-8 times a year , this is not surprising.
But an extensive review of 23 studies involving 6950 children and adults looked at how live bacterial supplements affect upper respiratory tract infections (URTIs) like the common cold and flu. The findings showed:
● Probiotics likely reduced the risk of recurring URTIs by 41%
● They may shorten the length of a URTI by approximately one day
● They likely reduced prescribed antibiotics for acute URTIs by 42%.
The combination of live bacterial strains LGG® and Bifidobacterium lactis, BB-12® - the world’s most published Lactobacillus and Bifidobacterium strains respectively - given to healthy infants and adults in high quality studies, has been clinically proven to lead to fewer respiratory infections, and a reduced length and severity of symptoms, compared to a placebo.
Other promising areas of research:
● Easing Traveller's Diarrhoea: If you’re venturing to regions with a high risk of diarrhoea (ever heard the phrase, Bali belly?), then LGG® may offer some protection. Studies have found that LGG® supplementation may help maintain a healthy poop consistency while traveling, potentially reducing the incidence of traveller’s diarrhoea.
● Irritable bowel syndrome in kids: While many people have heard of Irritable Bowel Syndrome (IBS), in science speak it is a disorder of the gut brain axis i.e. a dysfunction in the communication between the gut and the brain. ESPGHAN guidelines recommend LGG® supplementation in children with functional abdominal pain (FAP) and IBS, based on studies showing a lower frequency and intensity of abdominal pain, compared to a placebo.
Backed by over 40 years of scientific research, Lactobacillus rhamnosus, LGG® is one of the most studied live bacterial strains, and is known for its potential benefits in gut and immune health across all ages. Yet while a substantial body of evidence supports LGG®’s efficacy in certain conditions, it's crucial to remember that these effects are strain-specific – meaning they don’t automatically apply to other live bacterial strains or products promoted as ‘probiotics’, even within the same species (e.g. species: Lactobacillus rhamnosus; strain: HNOO1 has different functions to strain LGG®). So, make sure you look out for the right strain when choosing your live bacterial supplement. You can read all about this here.
Disclaimer: This blog post offers general information and should not be considered medical advice. As with any health intervention, it is always advisable to consult with a healthcare professional before taking any supplements.
Sources
· WGO Global Guidelines on Probiotics and Prebiotics. February 2023
· Szajewska et al. ESPGHAN Special Interest Group Position Paper. J Pediatr Gastroenterol Nutr 2023 Feb 1;76(2):232-247
· Leser and Baker. Microorganisms 2024, 12, 794.
· Armuzzi et al.2001a. Aliment. Pharmacol. Ther. 15:162-169 (n=60)
· Armuzzi et al., Digestion 2001b; 63:1-7 (n=120)
· Cremonini et al., Am J Gastroenterol 2002; 97 (11)
· Vanderhoof et al. J Pediatr 1999;135:564-568
· Szajewska et al. Aliment Pharmacol Ther 2007 Apr 15;25(8):871-81.
· Szajewska et al Aliment Pharmacol Ther 2011; 34: 1079–1087.
· Lancet Infect Dis. 2025 Jan;25(1):36–51
· NICE Clinical Knowledge Summaries. Prevalence of the Common Cold. Prevalence | Background information | Common cold | CKS | NICE
· Zhao et al. Probiotics for the prevention of acute upper respiratory tract infections. Cochrane Database Syst Rev. 2022 Issue 8. Art.No. CD006895
· Rautava et al. Br J Nutr. 2009; 101:172201726
· Smith TJ et al. Br J Nutr. 2013; 109: 1999-2007
· Oksanen et al . Ann Med 1990 Feb;22(1):53-6.
· Hilton et al. J Trav Med 1997 Mar 1;4(1):41-43.
Written by Rachel Redman - Registered Dietitian
Reviewed by Melissa Dadgar - NHS Specialist Pharmacist Prescriber
