Probiotics are friendly microorganisms that may help support healthy digestion and offer other benefits to your overall health.
When you consume probiotics, they influence the natural balance of microorganisms already living in your digestive tract, a diverse ecosystem known as your gut microbiome. Probiotics help crowd out harmful bacteria, and help inhibit inflammation, boost immunity, and produce neurotransmitters, among many other functions.
As additional research connects overall health to the health of the gut microbiome, probiotics are becoming a hot topic in the wellness industry. They’re being used as supportive therapies for everything from mental health to reproductive health, and many people take them as part of a daily wellness routine.
Probiotics operate in your gut microbiome, so gut health is one of the easiest places to notice their benefits. When you take probiotics in an adequate amount, they may affect the composition of your gut microbiome through several mechanisms.
Taking probiotics naturally increases the amount of beneficial microorganisms in your gut, leaving less space along the lining of your intestines for harmful pathogens to attach and multiply.
Probiotics also promote the production of antimicrobial substances, like short chain fatty acids and organic acids, and enhance the activity of certain immune cells, all of which help defend against harmful microbes.
Additionally, probiotics help improve the function and reduce the permeability of your intestinal barrier, preventing harmful pathogens from entering the bloodstream.
According to a comprehensive review from 2025, probiotics may successfully be used to help treat gut health challenges like irritable bowel syndrome (IBS), lactose intolerance, gastrointestinal infections, ulcerative colitis, and Crohn’s disease. They may also help manage bloating, diarrhea, and abdominal pain and may improve overall gut function.
Probiotics may help improve how well your body fights off infections and
Up to 80% of your immune cells are found in your gut, and the balance of your gut microbiome plays an important role in both local intestinal immunity and systemic immunity.
Beneficial gut microbes help train your immune system to tell the difference between harmful and harmless pathogens and strengthen your intestinal barrier and limit the growth of harmful pathogens in your gut through exclusion (called colonization resistance) and by promoting production of antimicrobial substances.
Your brain and your gut are connected through a two-way communication pathway called the gut-brain axis. This neurological connection makes it so that changes in your gut influence your brain activity, and brain activity may affect the functions of your gut.
If you’re feeling nervous, for example, you might notice you develop an upset stomach. Or, if you eat certain foods, you may feel like you can’t concentrate or your mood is low. This is all because of the gut-brain connection.
Imbalances in your gut microbiome, known as gut dysbiosis, may affect the production of hormones that influence your stress response and mood. It may also increase the permeability of your intestinal lining, allowing inflammatory substances to enter the bloodstream, where they may contribute to neuroinflammation in the brain.
Probiotics support hormonal balance, enhance nervous system function, and help reduce pro-inflammatory processes. The comprehensive review from 2025 notes probiotics may mitigate the effects of mental health disorders like depression, anxiety, and schizophrenia and may help with neurodegenerative conditions like Alzheimer’s disease.
Strains of probiotics that have shown to be beneficial for mental health include several strains of Lactobacillus and Bifidobacterium, including:
- L. helveticus
- L. casei
- L. rhamnosus
- L. plantanum
- B. breve
- B. longum
Just as your brain and your gut are connected through a two-way communication axis, your skin and your gut are connected through the gut-skin axis. Both the skin and the gut have complex, extensive microbiomes, and dysbiosis in the gut-skin axis has been linked to skin conditions like eczema, rosacea, psoriasis, and acne.
The gut-skin axis is an immune and neurologic network. Active immune responses from gut dysbiosis may cause systemic inflammation that affects skin barrier functions like sebum production and collagen regulation. Neurological gut dysbiosis responses, like increased production of stress hormones, may make skin inflammation worse.
In other words, when your gut microbiome is imbalanced, increased intestinal permeability, stress hormone production, and inflammatory processes may negatively affect the microbiome of your skin, compromising its natural immunity.
Because probiotics support proper gut function and immunity, they may help reduce inflammatory processes that compromise your skin barrier.
According to a review from 2023, probiotics may help:
- reduce overproduction of pigment
- keep skin moisturized
- reduce body odor
- prevent wrinkles, premature aging, and UV-radiation damage
The composition of your gut microbiome may impact your weight management. According to a review from 2023, a person’s microbiome influences how their body stores fat, the hormones related to hunger sensation, and how much energy is pulled from food during digestion.
The same review notes that because of these functions of the gut microbiome, probiotics are capable of combating several factors associated with obesity. They may inhibit fat accumulation, reduce low-grade inflammation, and improve insulin resistance.
Probiotics are living microorganisms that provide health benefits when consumed in adequate amounts. They won’t cause diseases like harmful pathogens, and they support a variety of gut microbiome functions that positively impact organ systems throughout the body.
Probiotics may help improve your gut health, and they may also support your skin health, mental health, immunity, and weight management goals.