The conference room in Brussels fell unusually quiet when Mike Holland put a simple number on the screen: more than €10 billion a year. Not the size of the EU probiotic market, not R&D investment – but the potential annual savings in healthcare and productivity if probiotics were used more widely as preventive tools across Europe.

For the first time, probiotics – long relegated to the grey zone between food and medicine – have been subjected to the same type of socio-economic scrutiny that EU institutions usually reserve for air pollution or hazardous chemicals. The result is a comprehensive Socio-Economic Impact Assessment (SEA) commissioned by IPA Europe and prepared by Rud Pedersen Public Affairs together with Holland, a consultant who has spent decades valuing the health and economic impacts of policy choices for the European Commission, the European Environment Agency and the OECD.

From clinical benefit to economic value

The Brussels meeting was structured in two acts. First came the science. Dutch immunologist Ger T. Rijkers walked the audience through a global analysis of probiotic clinical trials: 504 studies, 73,558 patients and 405 different outcome parameters. 

When those trials were scrutinised using a stringent definition of success – significant improvement in at least one predefined clinical endpoint and a parallel gain in patient-reported quality of life – the picture was clear: across metabolic, gastrointestinal and other indications, probiotics consistently conferred measurable health benefits. Most of the studies used well-known strains such as Lactobacillus rhamnosus GG and Bifidobacterium animalis BB-12, but there was also a growing body of work on multi-strain formulations. 

In other words, the biological and clinical rationale for probiotics is no longer the weak link. Over the past two decades, microbiome research has shown how live microorganisms can modulate immune responses, restore microbial balance after antibiotic use, influence lactose digestion, support oral and vaginal health, and even affect mental well-being through the gut–brain axis.

The real novelty in Brussels lay in the second act: Holland’s attempt to translate those clinical effects into hard euros using the EU’s own Better Regulation methodology and the OECD System of Health Accounts.

Seven common conditions, one big bill

The SEA focuses on seven areas where the scientific evidence for probiotic benefits is strong and where the burden of disease in Europe is substantial:

  • antibiotic-associated diarrhoea (AAD) and restoration of gut microbiota after antibiotic use
  • upper respiratory tract infections (URTIs, mostly common colds and flu)
  • oral health
  • women’s reproductive health, particularly bacterial vaginosis
  • lactose intolerance
  • mental health via the microbiota–gut–brain axis
  • bowel function, with an emphasis on constipation in older adults.

For each of these, the team mapped three things: how many people are affected in the EU, what probiotics can realistically change (incidence, severity, duration of symptoms), and what those changes are worth when you add up direct healthcare costs, productivity losses and, where possible, intangible costs such as reduced quality of life.

Where robust “response functions” existed – relative risk reductions or odds ratios from meta-analyses – the team used them directly. Where the literature was thinner, they modelled the impact of a very modest 1% improvement in the burden of disease, precisely because that figure is easy to scale and conservative compared with many of the observed clinical effects.

Even under those cautious assumptions, the numbers are striking.

Where the savings come from

Take antibiotic-associated diarrhoea, a frequent complication of systemic antibiotics. AAD not only causes discomfort and prolonged recovery for patients; in hospitals it drives extra laboratory tests, additional medications, isolation measures, longer stays and occasional intensive-care admissions, especially in cases caused by Clostridioides difficile.

Using EU data, Holland estimates that C. difficile infections alone cost around €3.2 billion per year in direct healthcare expenditure. When other causes of AAD are included, the total burden is closer to €16 billion annually. Probiotics administered alongside antibiotics have been shown to reduce the risk of AAD by 37% in adults and 53% in children. Applying those effect sizes, the model suggests that wider prophylactic use of probiotics could save €1.2–1.7 billion per year on C. difficile-linked AAD and €5.9–8.5 billion when all AAD cases are considered.

A second example is respiratory health. Upper respiratory tract infections are so common that they are often dismissed as trivial, yet they generate a sizeable bill in GP consultations, prescriptions and, above all, lost work days. For the EU-27, the SEA estimates direct healthcare costs of URTIs at around €57 billion per year, with productivity losses ranging between €61 and €349 billion depending on the assumptions used.

Here, Holland’s team drew on previous modelling from Lenoir-Wijnkoop and colleagues in France. Extrapolated to the EU, and still focusing only on those patients who actually see a doctor (about one third of flu cases and just 1% of common colds), the preventive use of probiotics could yield €1.1–3.9 billion per year in combined healthcare and productivity savings. When the full burden of respiratory infections is considered, each 1% improvement in respiratory health attributable to probiotics corresponds to €1.2–4.1 billion in economic benefit annually.

The picture is similar in bowel function. Constipation affects up to 42% of older people in long-term care facilities, with clear implications for quality of life and staff workload. In this setting alone, the SEA estimates baseline costs at €3.8 billion per year in pharmaceuticals and nursing time. Clinical data suggesting a 28% reduction in constipation episodes with probiotic use translate into potential savings of around €1.4 billion per year, without even counting gains in the community-dwelling elderly or working-age adults.

For lactose intolerance, the model assumes that probiotic foods can reduce symptoms by about 50%, thereby allowing many individuals to consume dairy without discomfort. Given the knock-on effects on diet quality, bone health and productivity, the estimated benefit for paid and unpaid work is €7–9.5 billion per year.

In women’s health, probiotics added to standard treatment for bacterial vaginosis are estimated to improve first-line cure rates from 48% to 83%. That difference matters because BV is associated with preterm birth, greater susceptibility to sexually transmitted infections and pelvic inflammatory disease. Across the EU, raising cure rates to this level would reduce direct costs linked to BV and its co-morbidities by €1.9–3.9 billion per year.

Finally, when the team looked at oral health and mental health, they could not derive firm response functions, but they could estimate the value of incremental improvements. Given that poor oral health costs the EU €143–193 billion per year, a mere 1% improvement would be worth €1.4–1.9 billion annually. For mental illness and autism combined, each 1% improvement in symptoms and participation corresponds to around €5.9 billion in societal benefit.

When all these elements are added up, and after accounting carefully for overlaps and uncertainties, Holland concludes that the benefits of wider probiotic use in Europe comfortably exceed €10 billion per year, and could in reality be several times higher once intangible benefits and under-studied conditions are included.

“These are very common conditions”

Speaking after his presentation, Holland underlined that the analysis is deliberately conservative. The team only counted benefits where some reasonable link to probiotic use could be supported by published data, and in several domains settled for modelling a 1% improvement even though clinical trials often show much larger effects.

He also stressed that the conditions chosen – colds and flu, antibiotic-related diarrhoea, constipation, lactose intolerance, oral disease, bacterial vaginosis, mental health issues – are extremely common across the EU population. Many people suffer from several of them over the course of a year, and they frequently co-exist or lead to comorbidities such as cardiovascular disease or psychological distress. Better prevention in these areas, even if modest on an individual level, therefore translates into large system-level gains.

From a health-economic perspective, probiotics are unusual in that they sit at the crossroads of healthcare and everyday consumption. They are purchased by citizens in supermarkets or pharmacies, yet their cumulative impact – positive or negative – shows up in hospital budgets, sickness-benefit statistics and productivity figures. The Brussels study is one of the first attempts to capture that link in a structured way using standard EU impact-assessment tools.

A regulatory paradox

The SEA does not stop at numbers; it also highlights a striking regulatory paradox. Europe has a centuries-old tradition of fermented foods, a strong scientific base in microbiome research and substantial public investment in microbiome-related projects under Framework Programmes and Horizon Europe. Yet, under current EU food law, “probiotic” is not even a legally recognised category.

Because the term has been interpreted by the European Commission as a health claim in itself, its use on labels is tightly restricted. EFSA, for its part, has applied very stringent criteria to probiotic health claims, approving only a single generic claim to date (for live yoghurt cultures improving lactose digestion), while rejecting more than 350 others.

The result is regulatory fragmentation. Countries such as Italy, France and Spain have developed their own pragmatic guidelines, allowing the word “probiotic” to appear on foods and supplements under specific conditions, while others either prohibit the term or treat it as a mandatory but non-communicative descriptor.

For consumers, this patchwork creates confusion. A large survey across eight EU countries found that 57% of probiotic users feel poorly informed about whether products actually contain probiotics, and 79% would like clearer labelling. Holland’s report notes that, if better information persuaded even a portion of these consumers to use probiotics more consistently, the European market could expand significantly – with preventive health benefits and budgetary effects following closely behind.

For producers, the lack of harmonisation means higher compliance costs and legal uncertainty that can deter innovation and investment, particularly in new strains and formulations emerging from cutting-edge microbiome science.

What this means for doctors, policymakers and industry

The message from Brussels was not that probiotics are a magic bullet. Holland repeatedly pointed out that his work does not constitute a formal systematic review of all health and economic data, and that the analysis remains partial – particularly for intangible costs and for conditions such as neurodegenerative disease where the evidence base is still emerging. If anything, the bias in the SEA is towards underestimating the benefits.

But the combination of Rijkers’ clinical overview and Holland’s economic modelling leaves little doubt that ignoring probiotics in preventive strategies is no longer intellectually or fiscally neutral.

For clinicians, the findings strengthen the case for integrating evidence-based probiotic products into care pathways where benefits are most clearly documented – for example alongside antibiotics in high-risk patients, in the management of recurrent bacterial vaginosis, or as part of multi-modal strategies for constipation in older adults and lactose intolerance.

For policymakers, the SEA offers something they rarely have in this field: an order-of-magnitude estimate of what a more coherent probiotic policy could be worth in euros, using the same language and methods that underpin impact assessments in other sectors. It also suggests a route forward: formal recognition of the WHO/FAO definition of probiotics as a category, science-based and proportionate criteria for use of the term “probiotic” on labels and in communication, and a clear distinction between general descriptive use and specific health claims.

For industry, the implication is that aligning innovation pipelines with these seven high-burden conditions – and generating solid strain-specific data – could position probiotics not just as consumer wellness products, but as credible partners in EU strategies on life sciences, One Health and antimicrobial resistance.

In Brussels, Holland summed up his conclusions with characteristic understatement: even small improvements in common conditions, achieved through safe, widely acceptable interventions such as probiotics, can unlock savings on a scale that matters for national health budgets. The challenge now lies with regulators, healthcare systems and industry leaders to decide whether they are willing to treat probiotics as part of serious prevention policy – and not just as a line on the supermarket shelf.