Probiotics
Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.
Also known as Probiotic, Lactobacillus, Bifidobacterium, Multi-Strain Probiotic
Common doses
10-50 billion CFU
Best timing
Morning
Food
Take on an empty stomach
Interactions
2 known
Probiotics are live microorganisms that, when consumed in adequate amounts, confer a health benefit on the host. The term encompasses a vast range of bacterial and yeast strains, each with potentially different effects. This is why 'probiotics' as a single category is misleading; the effects are strain-specific.
The gut microbiome contains trillions of bacteria that influence digestion, immune function, mood, and metabolic health. Probiotic supplementation aims to support or restore a healthy microbial balance, particularly after antibiotic use, during travel, or in conditions like IBS.
Strain specificity is crucial. Lactobacillus rhamnosus GG has strong evidence for preventing antibiotic-associated diarrhoea, but that evidence does not automatically apply to other Lactobacillus species or strains. When choosing a probiotic, look for products that specify strains (not just species) and doses that match clinical research.
Key benefits
Digestive health
Specific probiotic strains support healthy digestion, reduce bloating, and may help manage IBS symptoms.
Immune function
Approximately 70% of the immune system is in the gut. Probiotics support immune function through gut barrier integrity and immune cell modulation.
Antibiotic recovery
L. rhamnosus GG and S. boulardii have strong evidence for preventing antibiotic-associated diarrhoea when taken during antibiotic courses.
Mental health
Emerging 'psychobiotic' research suggests specific strains may influence mood and anxiety through the gut-brain axis.
Available forms
Multi-Strain Capsules
The most common format. Look for products specifying strains (not just species), CFU count, and independent testing.
Single-Strain
Targeted approach. Choose based on the specific condition you want to address. Strain-specific evidence is strongest here.
Spore-Based (Bacillus)
Survive stomach acid well. Do not require refrigeration. Some evidence for gut barrier support.
Saccharomyces Boulardii
A probiotic yeast, not bacterium. Survives antibiotics. Strong evidence for preventing C. diff and traveller's diarrhoea.
Food sources
- Yogurt (with live cultures)
- Kefir
- Sauerkraut (unpasteurised)
- Kimchi
- Kombucha
- Miso
Upper intake limit
No established upper limit. Most products provide 1-100 billion CFU. More is not necessarily better; the right strain at the right dose matters more than CFU count.
Research summary
Strong evidence for specific strains in specific conditions (L. rhamnosus GG for AAD, S. boulardii for C. diff prevention, VSL#3 for ulcerative colitis). Moderate evidence for general digestive and immune support. The field is strain-specific; broad claims about 'probiotics' are less useful than claims about specific strains.
Known interactions (2)
Check your full stack
for interactions.
See what competes, what combines well, and when to take everything. Every interaction cites a published source.
Stack
6 supplements
Stack review
1 flagZinc and Iron compete for the same absorption pathway. Take at least 2 hours apart.
Supplements
This information is for educational purposes only. It is not medical advice and does not diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional.