Research
Probiotic Research
Plain-language summaries of the published probiotic research. Every summary links to its primary sources, and we never present popularity as evidence.
Prebiotics vs Probiotics
How international scientific consensus distinguishes probiotics from prebiotics: probiotics are live microorganisms, while prebiotics are substrates selectively utilized by host microorganisms, and products combining both are called synbiotics.
Published June 22, 2026Read the research →Probiotics and Antibiotic Diarrhea
What two 2021 meta-analyses of randomized trials report about probiotics taken with antibiotics and the risk of antibiotic-associated diarrhea in adults, including dose and safety findings.
Published June 22, 2026Read the research →Probiotics and IBS
What meta-analyses of randomized controlled trials report about probiotics and irritable bowel syndrome, including strain-specific effects on abdominal pain and overall symptom severity and important evidence limitations.
Published June 22, 2026Read the research →Probiotics and Immune Health
An evidence-first look at what randomized-trial meta-analyses report about probiotics and immune health, focused on respiratory tract infections, with attention to the modest effect sizes and remaining uncertainties.
Published June 22, 2026Read the research →Probiotics and Mental Health
An evidence-first look at what randomized controlled trials and meta-analyses report about probiotics and mental health outcomes such as anxiety and depressive symptoms, including where the gut-brain (psychobiotic) evidence is genuinely limited.
Published June 22, 2026Read the research →Probiotics and Skin
An evidence-first look at what randomized-trial meta-analyses report about probiotics and skin, focusing on atopic dermatitis prevention and treatment, plus the limits of the current data.
Published June 22, 2026Read the research →Probiotics and Weight
What randomized-trial meta-analyses report about probiotic supplementation and body weight, BMI, and related measures in adults with overweight or obesity, including the small and mixed nature of the effects.
Published June 22, 2026Read the research →Probiotics for Women
What randomized-trial meta-analyses report about Lactobacillus-based probiotics for bacterial vaginosis in women, including cure-rate findings, safety signals, and the limits of the current evidence.
Published June 22, 2026Read the research →Probiotics: How Many CFU?
What CFU doses of probiotics have actually been studied, and why the 'right' number of billion CFU depends on the strain and the endpoint rather than a single universal target.
Published June 22, 2026Read the research →Probiotics: What Qualifies and Why Strain Matters
Probiotics are live microorganisms that confer a health benefit when given in adequate amounts, and their effects are strain-specific.
Published June 19, 2026Read the research →