In the United States, probiotics have become a staple in the supplement market, promising benefits like aiding digestion, improving skin health, and promoting a flat stomach. Millions of Americans are investing considerable sums into these products, captivated by their potential health enhancements.

Probiotics consist of live microorganisms, often beneficial bacteria or yeasts, that are intended to bolster the natural microbial community within the gut. They aim to restore and maintain a healthy balance in the digestive system, acting as reinforcements to the body’s internal ecosystem.

The surge in probiotic popularity can be attributed to a blend of factors, including the increasing awareness of the gut’s significant role in overall health, amplified by influencers and wellness advocates who dominate platforms like TikTok. The growing body of research revealing links between gut health and aspects such as mood and metabolism has further fueled consumer interest in enhancing their gut microbiota.

Nevertheless, experts, including doctors and researchers, are urging the approximately 4 million Americans who regularly consume probiotics to temper their expectations. While these products can be expensive, ranging from $20 to over $60 for a month’s supply, many popular probiotics may not deliver the promised benefits or might be overestimated in their effectiveness.

However, a growing contingent of doctors and researchers now advise the roughly 4 million Americans taking probiotics to manage their expectations, as many popular products, which can cost anywhere from $20 to more than $60 for a month’s supply, are over-hyped and may not be effective for their intended use.

Experts told the Daily Mail that, in many cases, the efficacy of probiotics depends on the strains the capsules contain. The wrong strain will not produce the benefits people expect. 

Nicolette Pace, a registered dietitian nutritionist based in New York, told the Daily Mail: ‘Probiotics are promising, but the hype has far outpaced the science.

‘Supplements often contain strains chosen without strong data, and researchers still have not identified which strains reliably help specific conditions.’

According to microbiologists, healthy people who eat well do not need a daily probiotic, an expense they consider unnecessary (stock image)

Dan Jackowiak a nutritional consultant and holistic healthcare practitioner, told the Daily Mail: ‘Most of the time, when people take a random probiotic for bloating, gas, or IBS, good studies do not show a clear, consistent benefit.

‘Some studies show a little help, some show none, and the results don’t line up well. That’s why major gut health guidelines say there isn’t strong enough proof to recommend probiotics for most everyday digestive problems.’

The global probiotic supplement market, projected to surpass $65 billion this year, is fueled by claims that these products can address a vast spectrum of ailments, from digestive issues to mental health conditions.

The American Gastroenterological Association released a landmark verdict on probiotics in 2020, finding insufficient evidence to recommend them for most common gut conditions like IBS, Crohn’s and ulcerative colitis.

The group only endorsed specific probiotic formulations for three narrow uses, including preventing C. difficile, a type of bacterium that causes severe inflammation of the colon, in patients on antibiotics, preventing a serious condition in preterm infants and managing a complication of inflammatory bowel disease called pouchitis.

Pace told the Daily Mail: ‘Researchers haven’t yet matched specific strains to specific conditions, which means many supplements are created based on manufacturer preference rather than evidence. Some formulas are grounded in science, but many are not.’

She added that if someone chooses to use a supplement anyway, the most practical option is to select one containing many strains in hopes of better coverage. 

Popular probiotic supplements include the capsules pictured above

‘Just understand that a general “take a probiotic pill for overall health” approach is not strongly supported by clinical data,’ she said. 

Many people, however, report anecdotal evidence of their benefits and doctors tend to say they can continue taking them, as there is minimal downside or risk of severe health effects.

Jackowiak said: ‘The reason people feel like probiotics changed their lives is mostly that some people really do match with a strain that helps their specific gut situation. If you’re healthy and want better gut health, I would not start with probiotic pills.

‘The most reliable way to support your gut is still food, especially eating more kinds of plants and more fiber. That has more substantial evidence than taking a general probiotic.’

Since probiotics are sold as dietary supplements, the FDA does not test them for safety or effectiveness before they reach stores. This puts the responsibility on buyers to research whether a product’s claims are backed by real evidence. 

A research team from Georgetown University Medical Center examined 93 probiotic products bought from national retailers and found a significant gap between marketing and evidence.

Only 35 percent of the products could be linked to published clinical studies that proved their specific strains were beneficial at the doses provided.

The majority of products, 65 percent, might have been effective, but researchers could not verify this because the labels lacked the precise scientific information; namely, the exact strain designation and its dose, needed to check against medical databases.

Dietitian Nicolette Pace notes that the science on probiotics lags far behind the hype. Supplements often use strains without strong evidence

Contrary to common marketing tactics, the study found that more expensive products with multiple strains and higher doses were not more likely to be backed by evidence.

They found that simpler, less expensive products were more beneficial. The researchers concluded that the burden of proof falls on consumers, as companies rarely list clinical studies on their labels.

A 2018 study found that the probiotics’ ability to influence human health is far more individualized and limited than commonly believed.

Researchers discovered that while probiotic bacteria pass through the digestive tract and are detectable in stool, they are largely prevented from colonizing the gut lining by a person-specific defense mechanism.

This resistance is driven by an individual’s unique native gut microbiome, which acts as a barrier that determines whether probiotic strains can take hold and exert any meaningful effect, suggesting that the current ‘one-size-fits-all’ model for probiotic supplements is ineffective for a significant portion of the population.