If you have high cholesterol, you wouldn't try to treat it with a blood thinner. Someone with Crohn's disease wouldn't assume their symptoms could be controlled with a statin, but when it comes to supplements, knowing what to choose from the health store shelves may not be as easy.
This is especially true in the case of probiotics. Most of us know that taking them can be beneficial. If you have an upset stomach, have taken antibiotics or want to improve your digestive health, they can help rebuild and balance the good bacteria in the gut. Most of us will admit that we're not sure what the difference really is between one long-named strain and another, so we tend to go with the brand recommended by our friends or the product with the most spectacular advertising campaign. But according to research published in the journal Frontiers, when it comes to choosing probiotics we should choose strains based on the condition you're trying to treat.
“I always tell people to treat probiotics like they would any other medication,” says registered dietitian Megan Hilbert, who specializes in gut health nutrition. “You wouldn't expect someone to take heart medication if they had back pain. Research shows that using a generic probiotic isn't always helpful, and that taking specific strains for specific conditions may be more effective.”
So, how can you know which strains are most beneficial? Here’s our expert guide to the best probiotic strains to invest in.
Gut health: “A balanced microbiome in the gut helps break down food and aids in nutrient absorption and the production of postbiotics, including nutrients such as vitamins B and K, which have a positive impact on our health,” says Megan.
“Beneficial gut bacteria also create short-chain fatty acids (SCFAs), which have anti-inflammatory properties. An imbalance in the microbiome can lead to many common gut and digestive problems such as bloating, acid reflux, and irregular bowel movements.”
Lactobacillus and Bifidobacterium strains have been shown to help improve gut health, helping to maintain a healthy gut. Probiotic foods such as live yogurt, sauerkraut, kefir, kimchi, tempeh and kombucha contain these strains while prebiotic foods, such as oats, garlic, bananas and onions, help feed these healthy microorganisms.
Try: Healthspan Triple Action Biotic (£24.99 for 60)
Irritable Bowel Syndrome (IBS) Around 12 million people in the UK suffer from it. Symptoms can include abdominal cramps, bloating, diarrhoea and constipation. “Research shows that people who have an imbalance in gut bacteria (dysbiosis) are more likely to have IBS,” says Megan. “The latest evidence suggests that treating dysbiosis with nutritional therapy and probiotics may be helpful in treating symptoms.”
A report published in Gastroenterology & Endoscopy in January showed that Bacillus coagulans (BC) was effective in reducing the severity of IBS symptoms and abdominal pain. Another report published in Current Microbiology in 2020 found that S. boulardii CNCMI-745 may help reduce IBS symptoms, while Lactobacillus plantarum 299v normalizes stool and reduces abdominal pain. S. boulardii may also reduce the incidence of traveler's diarrhea.
Try: Thorne Bacillus Coagulans (£22.19 for 60) or Optibac Travel Abroad (£14.99 for 20)
Swelling: “Dysbiosis due to increased fermentation in the gut can cause slower transit times and excessive bloating,” says Megan. “Studies have shown that Bifidobacterium animalis ssp. lactis, Lactobacillus rhamnosus, and Saccharomyces boulardii can help.”
Try: Optibac Saccharomyces Boulardii (£8.99 for 16)
Psychobiology and Mental Health: Psychobiotics describes the use of probiotics to benefit and improve mental health. “The gut and brain are in direct contact with each other through the enteric nervous system,” says Megan. “By improving the gut microbiome, it may help reduce inflammation, including neuroinflammation, which can cause cognitive and mood disorders.”
In a meta-analysis published in Microorganisms this February, it was shown that specific strains of probiotics can reduce depressive symptoms and anxiety. The research suggests that probiotics may provide a non-drug based approach in the treatment of mood disorders.
In another study published in the journal Nutrients, a strain called Lactobacillus plantarum PS128 proved effective in reducing anxiety, depressive symptoms and fatigue, and improving sleep. Meanwhile, a study on stressed students published in the International Journal of Microbiology showed that Lactobacillus plantarum 299v reduced stress and anxiety by lowering cortisol levels.
Other beneficial strains for stress and anxiety include: Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus casei Shirota.
Try: VSL#3 Concentrated Probiotic (£55.99 for 30 sachets)
Skin health: “Skin problems are often related to gut and digestive issues,” says Megan. “Poor gut health also affects hormones, which can lead to skin problems. By improving the balance of gut bacteria, this will lead to healthier skin.”
To improve skin health, choose probiotics that contain Lactobacillus rhamnosus GG, which helps reduce inflammation and has also been proven beneficial in managing eczema and atopic dermatitis. Meanwhile, Lactobacillus casei supports the skin barrier and helps reduce the risk of infection and inflammation. It is beneficial for dry and acne-prone skin.
Finally, Bifidobacterium breve helps maintain skin moisture. Studies show that this strain may also help reduce the severity of atopic dermatitis and improve skin texture.
Try: Symprove Daily Essentials Supplement (£49.99 for a one-month supply)
oral health: Many probiotic strains are beneficial for oral health. In a 2023 meta-analysis in the journal Frontiers, it was shown that probiotics can significantly reduce abnormalities such as tooth decay, fungus in the oral cavity, infections, and inflammation of the gums and palate.
“Certain probiotic strains can inhibit the growth of cariogenic bacteria such as Streptococcus mutans, which is primarily responsible for tooth decay,” says dentist Dr. Jasmine Piran. “Therefore, using products that contain specific strains may be effective in promoting oral health and preventing various oral health problems. But ask your dentist for advice.”
So far, there are 10 main strains, each of which performs a specific function. To reduce tooth decay, use Lactobacillus reuteri. It reduces the levels of Streptococcus mutans, which can cause tooth decay. This strain is also helpful in managing gingivitis and periodontitis by reducing inflammation and harmful bacteria.
Lactobacillus rhamnosus inhibits the growth of microbes associated with tooth decay and periodontal disease, and Bifidobacterium lactis supports gum health by reducing inflammation and pathogenic bacteria.
For fresh breath, look for Lactobacillus salivarius and Streptococcus salivarius strains. These can reduce bad breath (halitosis) by reducing the levels of odor-producing bacteria. Bifidobacterium bifidum, Lactobacillus johnsonii, Lactobacillus crispatus and Lactobacillus jensenii all produce hydrogen peroxide. This has antibacterial effects, killing pathogenic bacteria and helping to break down plaque, which causes gum inflammation that leads to gum disease.
Streptococcus oralis and uberis (which occur naturally in the mouth) help maintain a healthy balance of oral flora.
Try: Prodentim Advanced Oral Probiotics (£24.99 for 60)
Boosting immunity: About 70 percent of your immunity is located in the digestive system. So maintaining a healthy microbiome improves immunity and helps prevent infections.
To boost immune health, choose probiotics that contain: Lactobacillus rhamnosus GG. “Research shows that this strain may enhance the body’s immune response by increasing the activity of natural killer cells and T lymphocytes, which are important components of the immune system,” says immunologist Dr. Jenna Macciochi. “Studies also demonstrate that Lactobacillus rhamnosus GG may reduce the duration and severity of respiratory infections.”
Bifidobacterium infantis 35624 helps regulate the immune system, making it less likely to overreact to harmless substances and may help reduce the incidence of allergies. “Research suggests that Lactobacillus reuteri may help reduce symptoms of autoimmune diseases such as rheumatoid arthritis by modulating the gut microbiota and reducing systemic inflammation.”
Try: Gut Love by The Naked Pharmacy (£37)
Gynecological health: Urinary tract infections (UTIs), including cystitis, are caused by bad bacteria entering the urinary tract and causing an infection. “The most common cause of a UTI is E. coli,” says consultant gynaecologist, Dr Jo Bailey. E. coli normally travels from the gut through the rectum, which is close to the urethra.
You're more likely to get a UTI if you're sexually active.” Also, during menopause, a decrease in estrogen can cause the lining of the urethra and bladder to become thinner and produce less lubrication. This can cause changes in the microbiome, so it becomes more susceptible to bad bacteria.
“Certain probiotic strains may inhibit the growth of the bad bacteria that commonly cause UTIs.”
To improve urinary and vaginal health, choose probiotics that contain Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus jensenii, and Lactobacillus rhamnosus. Research suggests that only three or four of these essential Lactobacillus species are needed to keep the vaginal microbiome healthy. These bacterial strains help maintain an ideal vaginal acidic pH and a range of antimicrobial compounds that protect the vagina from infection.
Try: VJJ Ultimate UT (£26 for a one-month supply)