5 Research-Supported Benefits of Probiotics

Probiotics are live microorganisms that can alter the natural mix of bacteria and other microbes in your digestive tract, an ecosystem known as the gut microbiome. They may help keep harmful bacteria in check while also supporting immune function, lowering inflammation, and producing neurotransmitters, among other roles.

As more research links the gut microbiome to overall health, probiotics have become a major focus in the wellness world. They are now being used as supportive options for concerns ranging from mental health to reproductive health, and many people include them in their everyday routines.

Although probiotics are not the only thing needed for good health or measurable improvement, studies suggest they may offer benefits across several body systems and processes.

This article is part of Healthline’s Gut Check digestion challenge.

If you missed earlier entries, you can also read about fast constipation relief or continue to the next topic on IBS and IBD.

Probiotics may help balance the gut microbiome and support digestive health

Medical Perspective

“From what we know, having a variety of probiotic strains in our gut leads to a healthier gut microbiome, which in turn imparts a number of health benefits for the body, including supporting the immune system, reducing inflammation, controlling blood glucose, decreasing colon cancer risk, weight management etc. Having more good bacteria in the gut also helps crowd out the harmful bacteria.”

_{Quotes represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.}

When you get enough probiotics, they can change the makeup of your gut microbiome.

They may do this by increasing the number of helpful microorganisms in the gut through several different mechanisms.

For one, they can help reduce harmful pathogens in the intestines by limiting access to the nutrients those microbes need to grow and by improving the health of the intestinal barrier.

Probiotics may also produce antimicrobial compounds such as short-chain fatty acids and organic acids, while boosting the activity of certain immune cells that help defend against harmful microbes.

In addition, probiotics can improve intestinal barrier function and reduce its permeability, which may help prevent harmful pathogens from entering the bloodstream.

According to a comprehensive review, probiotics may help manage a range of digestive conditions, including:

• irritable bowel syndrome (IBS)
• lactose intolerance
• gastrointestinal infections
• ulcerative colitis
• Crohn’s disease

They may also ease bloating, diarrhea, and abdominal pain, while supporting better overall gut function.

Probiotics may lower inflammation and strengthen immunity

Probiotics may improve your body’s ability to fight infection and may also help reduce inflammation by helping regulate immune activity.

Up to 80% of immune cells are located in the gut, and the balance of the gut microbiome plays a key role in both intestinal immunity and whole-body immune health.

Helpful gut microbes can aid the immune system in distinguishing harmful from harmless pathogens. They may also reinforce the intestinal barrier and slow the growth of harmful microbes through colonization resistance and the production of antimicrobial substances.

Because they may reduce inflammation and support immune function, probiotics also show promise for helping manage inflammatory and immune-related conditions.

Probiotics may support mental health

The brain and gut communicate through a two-way pathway called the gut-brain axis. This connection means that changes in the gut can influence brain activity, and brain activity can affect gut function.

For example, if you feel anxious, you might notice stomach upset. Likewise, certain foods may leave you feeling foggy or low in mood. These responses are tied to the gut-brain connection.

When the gut microbiome becomes unbalanced, a condition known as gut dysbiosis, it may affect hormones involved in stress and mood. It may also increase intestinal permeability, allowing inflammatory substances into the bloodstream, where they could contribute to neuroinflammation in the brain.

Probiotics may help support hormonal balance, improve nervous system function, and reduce pro-inflammatory activity.

Research reviews note that probiotics may help lessen the impact of mental health conditions such as depression, anxiety, and schizophrenia, and may also support people with neurodegenerative conditions like Alzheimer’s disease.

Probiotic strains associated with mental health benefits include several Lactobacillus and Bifidobacterium species, such as:

• L. helveticus
• L. casei
• L. rhamnosus
• L. plantanum
• B. breve
• B. longum

Probiotics may help protect skin health

Just as the brain and gut are linked through the gut-brain axis, the skin and gut are connected through the gut-skin axis. Both organs have complex microbiomes, and research has connected gut dysbiosis with skin issues such as eczema, rosacea, psoriasis, and acne.

The gut-skin axis also involves the immune system and nervous system. When gut dysbiosis is present, it may trigger immune responses such as widespread inflammation, including inflammation in the skin. This can affect functions such as sebum production and collagen regulation. Other immune responses related to gut dysbiosis, including increased stress hormone production, may also worsen skin inflammation.

In short, an imbalanced gut microbiome, increased intestinal permeability, stress hormones, and inflammatory processes may all negatively affect the skin microbiome and weaken its natural health and defenses.

Because probiotics support healthy gut function and immunity, they may help reduce inflammatory processes that interfere with the skin barrier.

According to a review, probiotics may help:

• reduce overproduction of pigment
• keep skin moisturized
• reduce body odor
• prevent wrinkles, premature aging, and UV-radiation damage

More research is still needed, but some studies have linked oral and topical probiotic treatments to improvements in eczema, rosacea, acne, and psoriasis.

Probiotics may help support a moderate weight and lean mass

The gut microbiome may influence body weight and body composition, meaning the balance of fat and muscle in the body.

According to a review, the microbiome can affect how the body stores fat, the hormones tied to hunger, and how much energy is extracted from food during digestion.

The same review says these effects suggest probiotics may influence several factors tied to obesity. For instance, they may reduce fat buildup, ease low-grade inflammation, and improve insulin resistance.

A review of six studies found that probiotic use may be associated with lower body weight, body mass index, total body fat, and waist circumference.

FAQ

Taking probiotics every day may benefit digestive, skin, immune, and mental health.

Still, results can vary depending on the probiotic strain, your overall health, and the quality of the supplement. Some people also experience side effects such as bloating or stomach upset, especially when starting out.

Talk with a doctor to find out whether probiotics may be a good fit for you, which type might make the most sense, and what kind of benefits you might expect.

More research is needed to confirm whether probiotics help during or after antibiotics and to determine the best way to use them. Current research is mixed, with some studies reporting possible downsides such as more antibiotic-resistant genes and poorer recovery in the gut lining, while others report better recovery of helpful microbes.

Some experts suggest waiting until you have finished your antibiotic course before starting probiotics.

Probiotics may help ease constipation symptoms. Species that have shown benefits in research include B. lactis, L. casei shirota, and other Bifidobacterium and Lactobacillus species.

However, whether they are appropriate for you depends on the cause of your constipation. Since probiotics may take a few weeks to produce noticeable effects, they may be best for mild, gradual support.

Before using any supplement, including probiotics, to treat a medical condition, speak with a doctor.

The bottom line

Probiotics are living microorganisms that can provide health benefits when taken in sufficient amounts. They do not cause disease the way harmful pathogens do, and they support many gut microbiome functions that can affect organ systems throughout the body.

While they usually cannot treat health conditions on their own, probiotics may help improve gut health and may also support skin health, mental health, immunity, and weight management.