There’s a lot of hype about probiotics – and consumer interest is outrunning their understanding of the evolving science
Probiotics—and prebiotics—are a growing and swiftly-evolving product segment in Australia, with consumers keenly interested in finding out more.
A poster presented at the Choosing Wisely 2019 Annual Meeting earlier this year looked at the most-common queries Australians have about their complementary medicines—and which medicines they’re asking about.
Of the 42,000 calls received by the National Medicines Line service between January 2014 and December 2018, more than 2000 were about complementary medicines. Probiotics were the third-most asked-about items, with 8.4% of these calls pertaining to them (fish oil was first, and magnesium second).
And an April 2016 report by Ethical Nutrients found that 2.9 million Australians had recently consumed a probiotic supplement with the intention of restoring “gut health balance”.
The report, which surveyed 1020 Australians aged 18 to 64 who viewed themselves as “health-conscious,” also found that three in five did not understand the importance of storage.
“There’s a huge level of interest in probiotics,” says Jacqui Hagidimitriou, a pharmacist at the award-winning Terry White Chemmart Samford and winner of the Bioceuticals Integrative Medicine Award. She is also currently pursuing a degree in nutrition.
“The people who give you a funny look when you mention them and ask, ‘what’s that?’ are rare nowadays.
“Of natural medicines, multivitamins are probably the number-one thing that people have taken, and probiotics would be the second.”
If foods such as kombucha or fermented milk products are added to the equation, probiotics would likely be the most-taken complementary medicine of all, she says.
The knowledge gap
While interest is high, understanding is not as extensive, say stakeholders—particularly given the science to support probiotics is evolving rapidly.
Professor Terry Bolin, president and founder of the Gut Foundation, says that the product range and any evidence to support it will likely look very different in just a few years, which makes it difficult for consumers to keep up.
“I don’t think they understand the subject very well at all,” says Prof Bolin. “For example, the normal population has one to two kilograms of bacteria in their bowel, and a huge variety—400 different types of bacteria—and so you’re attempting to change that bacterial population for the better by taking probiotics.
“There’s a huge amount of hype around probiotics, and not all of it is confirmed,” Prof Bolin said. “They’re said to be good for irritable bowel, bloating and constipation, and it’s true that some of them do work.
“But you can’t put them all in the same basket, because they all have something different—usually it’s a combination of bacteria you have in the product.”
Consultant pharmacist Debbie Rigby said that when talking about probiotics, she often discusses the “hype, hopes and hoops” of the sector.
“There’s a lot of advertising on TV and on other media, and like with many complementary medicines and diets, they’re looking for a magic cure,” she said.
“And it’s such an expanding area. Only a few years ago we didn’t have a huge amount of evidence. The earlier trials were done in mice. And animals are not human, so we can’t extrapolate that data.
“Many of the studies also show correlation, not causation, so that’s something else to consider. But I think where we’ll be in a few years’ time will be quite different, given the amount of good research that’s underway now, and that greater understanding of the gut microbiome, what disrupts it and how we can change that back to a healthy microbiome.”
Looking at strains
Debbie Rigby said that the growing trend in products available in pharmacy and health food shops is to be specific to certain strains used to treat or manage certain conditions, based on supporting evidence.
She said that evidence for Lactobacillus reuteri for treatment of infant colic has been around for a while, but this did not translate into product availability.
“Unfortunately a lot of the research—new, and in the past—was done on strains that are not available as a specific product,” she told the AJP.
“There were some previous studies on this, but it’s only recently that we’ve had a product available on the market that’s been shown to have some efficacy in colic in infants. It doesn’t magically get rid of it, but it reduces the intensity and severity and the number of crying periods. Any little bit helps.”
A very common reason for probiotic use is in the management of antibiotic-associated diarrhoea.
“The products are now very specific, and the evidence supports the lactobacillus and bifidobacteria, as well as saccharomyces boulardii.”
The latter, which is actually a form of yeast rather than a bacterium, is the Samford TerryWhite Chemist’s top-selling probiotic, says Ms Hagidimitriou.
“We still call it a probiotic, because it does help the growth of bacteria even though it’s a yeast. These can be any kind of microorganism that will be beneficial once ingested.”
She said this product can also be used to manage traveller’s diarrhoea, and that pharmacists could help travellers by encouraging them to take it before they leave on a trip, and while they’re away, to help prevent an attack.
Debbie Rigby agreed, pointing out that some people may be more susceptible to traveller’s diarrhoea while in a developing country.
“PPIs, for example. If you’re taking them for reflux or dyspepsia long-term, there’s some evidence that you may be more susceptible to traveller’s diarrhoea because you haven’t got the acid in your stomach to kill off those bugs you’ve eaten. So there’s some evidence that saccharomyces boulardii can be used prophylactically.”
Ms Rigby says that the “other piece of the puzzle” is quantity.
“We have to have the right strains, but in the right quantity,” she says. “The term they talk about is Colony Forming Units—CFUs—and in general, more is better. So you’re looking at products with 10 to 20 billion CFUs.”
As well as probiotics, there are also prebiotics to consider. A prebiotic is “any kind of fuel or food” that will stimulate the growth of “good” bacteria in the gut, says Jacqui Hagidimitriou.
“It’s usually fibre: we can’t break it down, but the bacteria in our bodies can. Different fibres, as well, stimulate the growth of different bacteria. When you make a dietary change, it influences the growth in bacteria.
“For example, in babies, oligosaccharides found in breast milk are a prebiotic which can be added to infant formula, to help with the baby’s gut bacteria.”
Not everybody should be recommended a probiotic with every script or purchase, Debbie Rigby warns.
“I think we need to be a bit more judicious in recommending them to patients,” she told the AJP.
“Yes, if someone is on multiple courses of antibiotics, if they’ve had a past history of conditions like Clostridium difficile, they should be taken for the duration of the antibiotic treatment and continued for a week thereafter.
“Thrush and urinary tract infections are two conditions where probiotics are promoted, but the evidence is very very weak in that area. All you can say as a pharmacist is that ‘the evidence is weak’.
“You’ll always have people who swear by it, but as pharmacists we need to be guided by evidence. There have been some systematic reviews and meta-analysis, and largely they say that there’s at best moderate evidence for their use in conditions like traveller’s diarrhoea and colic.
“There’s also the issue that with traveller’s diarrhoea, for example, it’s there for protection, and not for treatment. There really isn’t good evidence for their use in treatment.
“Instead we should be treating with things like fluids, electrolyte replacement and anti-diarrheals if appropriate.”
Deanna Mill, PhD student at the School of Allied Health – Pharmacy, University of Western Australia, who has a background in hospital pharmacy, said that understanding about probiotics in pharmacists is “varied”.
“Most have general understanding of the concept of intended benefits and use, however large amount of varied information sources such as drug reps and advertising confuse this,” she warned.
“I also think there is very limited understanding of potential risks—particularly use in immunocompromised patients.
“Some pharmacists will recommend them for patients experiencing IBS and other gut ailments or post antibiotics as an adjunct to other treatments with recommendation for follow up with a medical professional,” she said.
“Most pharmacists I know and myself included would be more likely to check the safety of ongoing use within the context of the patient’s current health and other medications rather than recommend them as something to initiate.”
Debbie Rigby said that there was emerging evidence to support the use of probiotics in pregnancy to help prevent allergies and eczema, but “right now, it’s just weak evidence.”
She also cautioned against the use of probiotics in immunocompromised patients “in any way”.
“Having said that, I think probiotics are largely safe. ‘First, do no harm’—so we can feel confident that even if a probiotic might not be beneficial, it’s unlikely to do harm except to the person’s pocket.
“I tell people, as I do with all complementary medicines: if they want to give it a go, there is some weak evidence, so they can almost do a therapeutic trial themselves, for whatever they’re treating, such as IBS.
“Take it for a month or two, and if you feel some benefit, sure, keep going. But if you don’t, don’t waste your money.”
Deanna Mill said that while “do they work?” is the most frequently-asked question she has fielded, the first is whether probiotics will require refrigeration.
Jacqui Hagidimitriou said that while not all probiotics need to be stored in the fridge—and those that do have a little flexibility—there are a number of issues to consider.
“The ones that are shelf stable have to be overpacked with extra bacteria to account for the die-off rate,” she said.
“Sometimes that will upset people’s stomachs. The more bacteria, the more likely they may get some sort of wind. Whereas with those that are stored in the fridge, the number will be what the label says.
“Even with those which need refrigeration, if the person is going away, say on holidays, they can actually use it for a few days without storing it in the fridge. It’s not going to die off straight away. This does depend on the temperature, and each product would have different recommendations, but you do have several days in which they’ll still be effective.”
What about diet?
People also ask whether foods—such as kombucha, miso or fermented dairy drinks—can be used as an alternative to products stocked at pharmacies, and whether they have the same effect, said Ms Mill. Miso, sauerkraut, kefir and tempeh also have probiotic properties.
Ms Hagidimitriou and Professor Bolin both said that when discussing probiotics for dietary issues, pharmacists should bear in mind that lifestyle could be the culprit.
“We run a dietary program here, and I tell people, if they’re asking about probiotics for IBS, that if they don’t change their dietary practices or lifestyle issues which may be causing the symptoms, probiotics might only help in the short term,” she said.
“You really want a complete change if there are problems, so if you stop the probiotics you retain the improvement in symptoms.”
Prof Bolin said that he suspects quite a number of Australians are not aware of the way certain non-probiotic foods can affect their gut, and the flow-on effect this can have.
“They don’t recognise that some of the things they eat, like fat in particular, and caffeine, can play havoc with your tummy, and that they should be careful with these foods,” he said.
“The first thing to do is look at diet, and ask, ‘What am I eating?’
“‘Am I eating enough vegetables, cereal, lean meat, and do I have a wide variety in my diet?’ I still don’t believe there’s a superfood. You can’t say, ‘look, eat this or drink this, it’s magic’. It may well do some good, but there are other approaches which may be more important.”