Do you know you’re home to roughly 100 trillion bacteria currently living in your gut, but they’re far from being lazy squatters. Some are working hard for you, helping to digest food, destroy disease-causing cells, or producing vitamins.
On the other hand, imbalances within this community of approximately 300 to 500 different bacterial species have been linked to gastrointestinal conditions such as irritable bowel syndrome (IBS), as well as to diseases like obesity, Type 2 diabetes, and allergies.
Maintaining the equilibrium of this complex ecosystem is increasingly viewed as essential to your health. Hence the popularity of probiotics - formulations containing live microorganisms like yeasts and bacteria, designed to rebalance your gut microbiome and maintain its population of helpful citizens. The global market for these pills, powders, drinks and drops was valued at around £48 billion in 2022, and was forecast to reach over £57.5 billion by 2027.
But how do you know which probiotic is perfect for your needs? While research into the microbiome is still in its infancy, studies are beginning to identify specific bacteria that battle certain health problems, and the formulations likely to be most effective in each case.
Settling post-antibiotic problems: try Invivo Bio.Me S. boulardii
Stomach feeling a little dodgy after a course of antibiotics? Taking antibiotics may disrupt the delicate balance of gut microbiota species, which can cause diarrhoea, nausea and vomiting. “A non-pathogenic yeast called saccharomyces boulardii has shown promising results in the case of post-antibiotic diarrhoea,” says Eve Kalinik, nutritional therapist, gut expert and author of Happy Gut, Happy Mind.
This yeast occurs naturally in the gut, and while it is just one of the many microorganisms depleted by antibiotic use, Kalinik confirms studies show it has a particularly positive effect on this symptom.
The good news, should you be midway through a prescription, is that you can buy capsules of saccharomyces boulardii (or SB) as a single-strain probiotic product – harnessing these proven benefits. Kalinik’s favourite? “I like the Invivo Bio.Me S. boulardii for their clinical-grade formula.”
Pro: does not need refrigerating
Con: comes in capsule form, which some people find hard to swallow
Cost: £25.50 for 60 capsules
Coping with UTIs and thrush: try Fem-Dophilus
“Lactobacillus rhamnosus GR-1 is also one of the most researched probiotic strains for women’s health,” says Kalinik. The bacteria produces lactic acid which lowers pH, improving the balance of the vaginal microflora and helping to protect against thrush and urinary tract infections. Kalinik has found Fem-Dophilus by Jarrow Formulas is a particularly effective formulation.
Pro: does not require refrigeration
Con: you need to remember to wait at least 1-2 hours between taking antibiotics and taking these
Cost: around £26.99 for 30 capsules
Alleviating skin issues: try Esse skincare products
“We have a microbiome on our skin that needs just as much nourishment as the one internally,” says Kalinik. These millions of different bacteria, viruses and fungi protect it from pathogens, helping to regulate your skin’s pH and more. While the science of topical probiotic application is still very much in its infancy, some research does suggest that imbalances in the skin’s microbiome can both cause and worsen skin conditions, and that people with atopic eczema have more of the bacteria Staphylococcus aureus in their skin microbiome.
A 2020 paper in the Clinical and Experimental Dermatology journal concluded that topical probiotics may help people with acne, while early research suggests probiotics can restore acidic skin pH, alleviate oxidative stress, reduce photoaging and improve skin barrier function. So for skin health, Kalinik favours “clinically designed and proven probiotic and prebiotic topical products,” like those from the Esse range. Unlike a lot of other pro and prebiotic skin products, the microbes in these are kept alive, she explains.
Pro: smells great
Con: expensive
Cost: Esse’s Probiotic Serum will set you back £105.50
Tackling IBS: try Symprove
An estimated 13 million people in the UK suffer from irritable bowel syndrome, an overarching term for inflammatory bowel conditions, including Crohn’s disease and ulcerative colitis. “These are conditions where the body’s own immune system is reacting to something in the gut, and many patients with IBS have an imbalance of bacteria in their gut microbiotas,” says Simon Gaisford, Professor of Pharmaceutics at University College London.
To correct this imbalance, and mitigate symptoms such as bloating, wind and cramping, Prof Gaisford recommends Symprove. “The probiotic bacteria in Symprove have been shown to grow effectively in the gut,” he says, “and they can help to rebalance the gut microbiota towards that seen in people with no underlying disease conditions.”
Its particular efficacy is linked to its production through fermentation, which means that the bacteria develop a tolerance to acid, he explains: “so when swallowed by a person they are much more able to withstand the pH of stomach acid.”
In the professor’s own testing, 99.9 per cent of the bacteria in Symprove survived this journey into the gut. His own studies of the microbiotas of patients with ulcerative colitis bear this out. “We took stools from three donors with ulcerative colitis, determined how many good and bad bacteria there were and then added Symprove,” he explains. “We saw the number of good bacteria increase and the number of bad bacteria decrease.”
However, most probiotic products are not made this way. Prof Gaisford explains: “they have freeze-dried bacteria added at the end of production and these have not had the chance to become acid-resistant.”
Pro: proven effective in clinical studies, such as Prof Gaisford’s
Con: the cost. Plus, it must be refrigerated and taken before any other food or liquid first thing in the morning
Cost: from £39.99 for a month’s supply
Treating childhood eczema: try Natures Aid Bio360 Kidz Pro-5
“I love the Natures Aid 360 for atopic skin issues like eczema,” says Lucinda Miller, the founder of NatureDoc, a UK-wide team of nutritionists, nutritional therapists and naturopaths, and author of kids’ cooking book The Good Stuff. The Natures Aid product contains two probiotic strains which are considered anti-inflammatory and helpful for atopic conditions.
“These are Lactobacillus rhamnosus and Lactobacillus casei,” says Miller. “Which have both been identified as strains that may help with cow’s milk protein allergy as well as childhood eczema. Lactobacillus strains help to digest milk products, they can also support immunity and they are thought to create an anti-inflammatory environment in the gut.” Miller claims some of her young clients have seen the condition of their skin improve in less than two weeks.
Pro: the powder is easily mixed into yogurt or a smoothie for picky eaters
Con: you can’t mix it with hot liquids (milk or water) and it does not mix that well into cold liquids either
Cost: £11.95
Battling children’s colds: try ProVen Fit for School
For young people’s general health and immunity, Miller recommends ProVen Fit for School - a chewable tablet with a combination of probiotic strains and vitamin C.
“It was used in the ProChild study, which took place over a six-month period throughout autumn and winter, looking at incidence of sneezing, coughs, runny nose, blocked nose and sore throat,” says Miller. “Children who took this probiotic blend had 33 per cent fewer upper respiratory tract infections, and if they did get any of these respiratory symptoms then they were sick for less time and 30 per cent less likely to be absent from school due to illness.”
Pro: chewable and sweet, and doesn’t need to be refrigerated
Con: the Fructooligosaccharides sweetener ingredient may give children a slight windy tummy
Cost: £15.95 for 30 tablets
For the menopause: try fermented foods
“As the menopause is a hormone deficiency, the optimal treatment is to replace the missing hormones by taking hormone replacement therapy (HRT),” says Dr Louise Newson, a GP and menopause specialist. However, she adds “a large proportion of the body’s serotonin is provided by the gut and there is significant evidence of a connection between the gut’s microbiota and overall mood.” Since low mood is a common menopause symptom, Dr Newson advises this makes supporting your microbiome a sensible move during this life stage.
And there’s more. An unhealthy gut microbiome can increase the risk of some heart conditions such as heart attacks (myocardial infarction) and coronary artery disease, she explains, while lower oestrogen levels, post-menopause, heightens the risk of cardiovascular disease too. “While HRT is again the best treatment to reduce cardiovascular disease risk in menopausal women, gut health is an additional consideration.” Dr Newson’s answer is to support your gut with both pre and probiotic foods.
“Prebiotics are foods which act as food for the good bacteria, and probiotics are foods which contain living strains of bacteria which bolster the population of good bacteria in your digestive system.
“Eating a good amount of prebiotic wholefoods, such as bananas, onions, garlic and asparagus, can feed the good bacteria already in your gut. Eating probiotics - fermented foods such as kombucha, sauerkraut, miso, and yogurt - will increase the good bacteria.”
Supporting your microbiome with a combination of these foods, helps to boost serotonin levels, and protect against cardiovascular disease, both of which are “incredibly important considerations for those going through menopause,” says Dr Newson.
Pro: easy to find in your local supermarket
Con: not the complete answer
Cost: variable, but rarely expensive
Maximising brain health and memory: try kefir
“Our gut and our brain talk to each other,” says Dr Emily Leeming, a scientific researcher at King’s College London, registered dietitian and the author of forthcoming book Genius Gut. This conversation occurs mainly via your vagus nerve, she explains: “One of the longest and far-reaching nerves in your body, it connects your brain to your gut and other organs and acts as a two-way messaging highway pinging feedback back and forth. Eighty per cent of these messages come from the gut to the brain.”
The fermented milk drink kefir has been proven to change the type of bacteria you have in your gut, but it has more benefits too. “It also improves how well you remember things like people’s names and faces, and where you last left your keys,” says Dr Leeming. “A study was done in healthy people, and early investigations are now examining if this could be helpful in those with dementia and Alzheimer’s disease too.”
Pro: it’s cheap to buy and you can even make it at home
Con: it can be tart and a bit fizzy, which might be a little off-putting for some
Cost: prices vary