The Best Probiotic Supplements for IBS

The role of gut bacteria in the onset and maintenance of irritable bowel syndrome (IBS) is a compelling topic for scientists. While the research is still limited, probiotic supplements are being studied around the world to see if they have the potential to reduce IBS symptoms.

Your large intestine is filled with thousands of strains of bacteria, often referred to as the gut flora. Having a favorable balance in your intestinal microbiome is known to help your body function optimally and stay healthy.

Probiotics are sometimes called "friendly" bacteria. It's believed that they support the immune and digestive system by keeping "unfriendly" gut bacteria in check. When unfriendly bacteria predominate (intestinal dysbiosis), it's believed that inflammation develops and may cause physical symptoms.

Taking a probiotic supplement may help maintain higher levels of helpful bacteria in the gut while reducing levels of unhelpful bacteria. If you have IBS, having balanced gut flora may help manage your symptoms.

Health Benefits

Studying the use of probiotics for IBS is complicated because it's difficult to make comparisons between the known species of bacteria in the human gut microbiome (around a thousand). Furthermore, researchers have yet to identify all the bacteria in the human gut nor are they certain of what each type does.

When researchers want to determine if probiotics can help specific conditions, the design of the study will affect how the findings are interpreted.

For example, if researchers wanted to see if probiotics reduce abdominal pain in people with IBS, they could set up a randomized controlled trial. The researchers would assemble two groups of people with IBS. One group would be given a probiotic supplement and the other would get a placebo (sugar pill with no active medication).

The study can also be "double-blind," which means that neither the participants nor the researchers know which group was given the "real" probiotic. This method helps researchers determine if participants are experiencing a placebo effect.

Studies of probiotics and IBS don't always use these methods. However, the ones that do seem to produce higher-quality results due to the rigorous process.

The results of probiotic studies for IBS have been mixed. Some have demonstrated positive effects of probiotics on symptoms while others have found little to no difference.

Probiotic supplements may:

• Reduce abdominal pain
• Decrease bloating and gas
• Improve overall IBS symptoms
• Normalize the frequency of bowel movements

How They Work

Researchers have noticed that in some cases, the balance of bacteria in the guts of people with IBS looks different than in someone without the condition. However, it's not clear if the imbalance causes IBS symptoms—or if IBS causes the imbalance.

Taking a probiotic supplement (thereby increasing the number of friendly bacteria in the large intestine) may help IBS symptoms in a few ways:

• Normalizing intestinal motility
• Reducing "unfriendly" bacteria
• Decreasing visceral hypersensitivity
• Eradicating small intestinal bacterial overgrowth (SIBO)
• Reducing pain by affecting nerve receptors found in the lining of the intestines
• Strengthening the intestinal lining and reducing intestinal permeability ("leaky gut")

Side Effects and Safety

Probiotic products may worsen or cause symptoms in some people, whether they have IBS or not. Temporary gas and bloating are sometimes reported in the first few weeks people try taking a probiotic. Depending on the ingredients, probiotics may cause symptoms, side effects, or reactions in people with other medical conditions or food allergies.

While there's no guarantee they will help, most people don't experience any serious side effects from taking probiotics. However, if you're concerned about the safety of a product, you'll need to check with the manufacturer.

Companies usually test their products for safety and effectiveness before they hit store shelves, but probiotic supplements aren't consistently regulated in the United States.

Probiotic supplements may not cause side effects for most healthy people, but that doesn't mean they're suitable for everyone. If you have certain health conditions, food allergies, or a weakened immune system, your healthcare provider might advise against taking probiotics.

What to Look For

While the evidence is limited, studies have indicated that certain strains of bacteria may influence IBS symptoms in some people with the condition.

Researchers don't yet know which strains are the most helpful for IBS, therefore probiotic supplements often combine more than one. These products may also include fiber and prebiotics (known as "symbiotics" when paired with probiotics).

Researchers have also begun to develop and patent probiotic formulas intended for clinical research. One example, VSL#3, has been used in several clinical trials for IBS. The greatest benefit was observed in people who took VSL#3 for pouchitis.

However, as pointed out by a 2018 systematic review and meta-analysis, the results of the studies were inconsistent and the research methods used were not particularly strong.

Choose a product that contains live strains of bacteria and be sure to check the manufacturer's suggestions for storing it. Some probiotics need to be refrigerated while others can be kept in a cool, dry place.

Probiotics in Food

In addition to supplements, food can also contain probiotics as a result of how it's prepared. Foods such as yogurt, traditionally prepared sauerkraut, and the Korean dish kimchi produce different strains of probiotic bacteria as a result of undergoing the fermentation process.

It's unclear if fermented food is specifically beneficial for IBS. The uncertainty is complicated by reports from some people with IBS who find that foods that have undergone fermentation make their symptoms worse.

One reason for this may be that fermented foods tend to be higher in short-chain carbohydrates called FODMAPs (fermentable oligo-, di-, monosaccharides, and polyols).

Some people with IBS find high FODMAP foods are more likely to cause or worsen their symptoms. According to Monash University testing, fermentation can increase a food's FODMAP content which may make it unsuitable for an IBS diet.

If you want to try adding fermented foods to your diet, start with small amounts and see how you tolerate them.

A Word From Verywell

If you have IBS, probiotics from food and supplements may offer positive benefits with minimal risk of side effects. However, more research is needed to strengthen the theory.

As with any over-the-counter product, talk to your healthcare provider before trying probiotic supplements or adding fermented foods to your diet. If you have certain medical conditions, your healthcare provider may not recommend probiotics.