As Thai consumers increasingly reach for probiotic supplements in the pursuit of gut health and general wellness, a wave of new international research is challenging the value of these products—and warning of potential risks for some individuals. The probiotic market, which ballooned to an estimated US$87.7 billion (about 3 trillion baht) globally in 2023, is projected to be worth even more in Asia, with Thailand among the countries seeing swift growth in sales at pharmacies, supermarkets, and online shops. But according to a recent investigation spotlighted by Fortune, many probiotic supplements may not offer meaningful health benefits, and under certain circumstances, they could even backfire for the consumer (fortune.com; msn.com).
The idea that ingesting “good bacteria” capsules or powders could improve digestion, boost immunity, or even influence mood has captivated global and Thai health enthusiasts for more than a decade. Large advertisement campaigns, celebrity endorsements, and social media “wellness” influencers have all helped popularize the image of probiotics as a fast track to better health. But fresh scrutiny of both new and existing clinical studies suggests that these supplements may not live up to the hype—and in some cases, could carry hidden risks (nccih.nih.gov; pubmed.ncbi.nlm.nih.gov).
Analysis from top Western medical journals and agencies, such as the US-based National Center for Complementary and Integrative Health (NCCIH), suggests that while probiotics can help certain cases of antibiotic-related diarrhoea or digestive disease, for most healthy people their benefits are questionable. According to leading gastroenterologists and microbiome experts, the benefits of widely available probiotic supplements are often overstated or not proven by high-quality clinical trials (“the source of many claims is not robust research, but industry-driven marketing,” argued a top US gastroenterologist in a recent Washington Post op-ed (msn.com).
The latest research adds an even more startling concern. A study published in early 2025 found that some probiotic supplements sold in global health markets—including online platforms accessible to Thais—contained genes that confer resistance to major classes of antibiotics such as tetracycline and macrolide (pubmed.ncbi.nlm.nih.gov; journals.asm.org). The theoretical risk is that these genes could transfer to harmful bacteria within the human gut, potentially making some infections harder to treat. This phenomenon of “horizontal gene transfer” is of particular concern to public health authorities worldwide, given the escalating problem of antimicrobial resistance (AMR).
For many Thai consumers, the image of probiotics as inherently “natural” or risk-free may also be challenged by another aspect of recent findings: for people with certain health conditions, including compromised immune systems, recent organ transplant recipients, or those taking immunosuppressive drugs (such as for autoimmune disease or cancer), probiotics may actually increase the risk of infection (frontiersin.org). There have been documented cases of rare but serious infections caused by the very same species of bacteria or yeast present in supplements, though these are still considered uncommon.
In practical terms for Thais, the cultural popularity of probiotic-rich foods—such as yoghurt (dairy and non-dairy), fermented vegetables (pak dong), and the iconic fermented fish (pla ra)—complicates the conversation. On one hand, traditional Thai diets have long relied on naturally fermented foods, associated with better gut health due to dietary diversity and the presence of live cultures. But on the other, many supplement manufacturers claim that their products offer superior benefits due to “clinically tested” strains or higher concentrations—claims that are rarely scrutinized by independent, peer-reviewed research.
According to an infectious disease specialist at a major Bangkok hospital, “The concept of supporting the gut microbiome through food is well supported by evidence. But with supplements, especially in pill or powder form, the situation is much less clear. Most healthy Thais get enough probiotic diversity from diet alone. Spending money on expensive supplements is often unnecessary.”
Meanwhile, Thai regulatory bodies are keeping watch. The Thai Food and Drug Administration (FDA) has approved select probiotic strains for use in foods and supplements, but comprehensive post-market surveillance or requirement for efficacy studies is limited compared with Europe or North America. Thai pharmacists contacted by the Bangkok Post say that most probiotics sold in Thai pharmacies are considered food supplements and thus face minimal regulatory barriers—meaning claims can sometimes outstrip the science.
Expert advice, both locally and internationally, is converging on the idea that most individuals are better off focusing on dietary sources of probiotics rather than unproven supplement products. As one Thai dietitian remarked, “If you’re healthy, the best way to help your digestive system is by eating a variety of fruits, vegetables, and naturally fermented Thai foods. There’s no shortcut in a bottle.” For those with medical conditions, consulting a doctor before taking supplements is essential, as the risk-to-benefit ratio can vary considerably.
There are also lessons from Thailand’s own past. Interest in imported supplements tends to peak in times of health anxiety—such as the Covid-19 pandemic or periods of increased disease awareness—but these trends have sometimes led to public health challenges. For example, the unregulated distribution of herbal or dietary products has in the past resulted in misuse, allergic reactions, or negative drug interactions for Thai consumers. Culturally speaking, there is also pride in the abundance of local probiotic foods woven into the fabric of Thai cuisine—a reminder that “innovation” is not always synonymous with superior health.
Looking forward, researchers recommend further local studies to assess both the prevalence and impact of antibiotic-resistance genes within Thai-sold supplements. Health authorities also highlight the need for updated consumer guidelines as the supplement market grows, with calls for clear, evidence-based labelling that distinguishes food products from health-promising pills.
For now, experts urge Thai consumers to be informed and skeptical of extravagant probiotic claims. Instead of investing heavily in imported supplements, Thais can reap equivalent or better benefits from age-old dietary wisdom. Practical steps include eating a colourful range of fruit and vegetables each day, regularly incorporating naturally fermented foods into meals, and consulting healthcare providers before starting any new supplement regimen—especially for children, the elderly, or those with underlying health conditions.
Sources: Fortune, NCCIH, PubMed, Frontiers in Microbiology, Washington Post Op-Ed via MSN, ASM Journals, Thai FDA.