Bacillus subtilis

Robust spore-forming probiotic bacteria that supports digestive health, immune function, and produces beneficial enzymes including nattokinase for cardiovascular health

Scientific nameBacillus subtilis FormulaSpore-forming bacterial culture Molecular weightN/A - Living spore-forming organism g/mol CASN/A - Probiotic strain

90 absorption score

9 safety / 10

30 USD per month

6 documented interactions

Check it against something

Evidence level B

Bacillus subtilis with:

78 out of 100

Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Enhanced digestive enzyme production

Produces various digestive enzymes improving nutrient breakdown and absorption

Secretes amylases, proteases, and lipases for comprehensive digestion Evidence A-grade 2-6 weeks of consistent supplementation

Improved cardiovascular health support

May support heart health through enzyme production and circulation

Produces nattokinase-like compounds supporting cardiovascular function Evidence B-grade 6-12 weeks of regular use

Strengthened immune system function

Enhances immune response and reduces infection susceptibility

Stimulates immune cell activity and produces antimicrobial compounds Evidence B-grade 4-8 weeks of consistent use

Exceptional survival and stability

Survives extreme conditions including high heat and acidity

Spore formation provides protection against harsh environments Evidence A-grade Immediate protection upon ingestion

Improved gut barrier function

Strengthens intestinal lining and reduces intestinal permeability

Produces beneficial metabolites and supports tight junction integrity Evidence B-grade 4-8 weeks of regular supplementation

Others take these for the same thing

Same goal, different mechanism — check any of them against this one

Probiotics for Autoimmune Disease Support Gut health & immune modulation 10-100 billion CFU daily B 60% Magnesium Glycinate Superior absorption sleep & muscle support 200-600 mg A 90% Coenzyme Q10 (CoQ10) Heart health & cellular energy 100-200mg A 10% Magnesium Citrate Balanced absorption & digestive support 300-600 mg A 35% Fish Oil (EPA/DHA) Heart & brain health 1-2g EPA/DHA A 85% Chloride Electrolyte & digestive support 2300mg A 95%

Every pair we checked

12 combinations scored by the engine

Bacillus subtilis + Caffeine No documented interaction either way No known interaction 70

Bacillus subtilis + Creatine Monohydrate No documented interaction either way No known interaction 70

Bacillus subtilis + Vitamin D3 No documented interaction either way No known interaction 70

Bacillus subtilis + Calcium Carbonate No documented interaction either way No known interaction 70

Bacillus subtilis + Whey Protein No documented interaction either way No known interaction 70

Bacillus subtilis + Lactase No documented interaction either way No known interaction 70

Bacillus subtilis + Bovine Collagen No documented interaction either way No known interaction 70

Bacillus subtilis + DHA No documented interaction either way No known interaction 70

Bacillus subtilis + Turmeric No documented interaction either way No known interaction 70

Bacillus subtilis + Nattokinase Synergistic cardiovascular benefits and circulation support Works better together 75

Bacillus subtilis + Digestive Enzymes Enhanced digestive enzyme activity and nutrient absorption Works better together 78

Bacillus subtilis + Prebiotic Fiber Complex Improved probiotic survival and beneficial metabolite production Works better together 82

Dosage

With meals daily

Daily1-3 billion CFU

Digestive enzymes1-3 billion CFU daily with meals

Cardiovascular support1-3 billion CFU daily with meals

Immune support1-3 billion CFU daily

Gut barrier support1-3 billion CFU daily

When to expect it

First Effects1-2 weeks for initial digestive enzyme improvements

Peak Benefits4-12 weeks for maximum digestive and cardiovascular benefits

Deficiency DevelopmentBeneficial bacteria depleted by antibiotics, processed foods, stress

Toxicity OnsetNo known toxicity - extremely safe probiotic

How to measure it

$200-400

MarkerDigestive enzyme levels, cardiovascular markers, immune markers

OptimalAdequate enzyme levels, healthy cardiovascular function

Deficient belowLow enzyme activity, poor digestive markers

FrequencyMonitor for digestive enzyme optimization and cardiovascular health

Works better with

3 documented

Digestive Enzymes

Enhanced digestive enzyme activity and nutrient absorption

Complementary enzyme production for optimal digestion · level B

Nattokinase

Synergistic cardiovascular benefits and circulation support

Both support cardiovascular health through enzyme pathways · level C

Prebiotic Fiber

Improved probiotic survival and beneficial metabolite production

Prebiotics provide nutrients for beneficial bacteria growth · level A

What not to take with Bacillus subtilis

3 documented

Extreme Heat Processing

Excessive heat may damage spores despite high tolerance

Very high temperatures can destroy spore viability · low significance

Artificial Preservatives

Some preservatives may reduce spore viability over time

Antimicrobial preservatives can affect beneficial bacteria · low significance

Chronic Stress

Long-term stress may impair probiotic effectiveness

Stress hormones affect gut microbiome and immune function · moderate significance

Medication interactions

Discuss these with a pharmacist before combining

antibiotics Beneficial

B. subtilis spores can survive most antibiotics

What to do: Can be taken during antibiotic treatment

anticoagulant-medications Minor

Theoretical interaction with blood thinners due to enzyme production

What to do: Monitor if taking blood thinning medications

Available forms

bioavailability compared

Bacillus subtilis (Various strains) 90

Bacillus subtilis (Various strains): Enzyme production, Extreme stability, No refrigeration, Cardiovascular support

Food sources

before you supplement

Natto (fermented soybeans) 10^8-10^9 CFU per serving · 85

Fermented soy products 10^6-10^8 CFU per serving · 75

Soil-based organisms (environmental) Natural environmental presence · 50

B. subtilis probiotic supplements 1-10 billion CFU per serving · 90

Too little

deficiency signs

Digestive enzyme insufficiency symptoms:
Poor digestion and nutrient malabsorption
Digestive discomfort after meals
Compromised cardiovascular function
Frequent infections and immune system weakness
Increased intestinal permeability and gut barrier dysfunction
Reduced resistance to gastrointestinal pathogens

Too much

toxicity signs

Generally safe with minimal adverse effects:
Temporary digestive adjustment during initial supplementation
Very rare bacterial overgrowth in severely immunocompromised
No documented serious adverse effects in healthy individuals
Safe for daily long-term use

Who benefits most

digestive-enzyme-deficiency

Produces multiple digestive enzymes improving nutrient breakdown

1-3 billion CFU daily with meals

cardiovascular-health-support

May support heart health through enzyme production and circulation

1-3 billion CFU daily with meals

immune-system-support

Strengthens immune function and reduces infection risk

1-3 billion CFU daily

gut-barrier-dysfunction

Strengthens intestinal barrier and reduces leaky gut syndrome

1-3 billion CFU daily

digestive-stability-seekers

Provides stable probiotic benefits without refrigeration requirements

1-2 billion CFU daily

Where to buy it

compare forms first

Look for Bacillus subtilis at 1-3 billion CFU per serving. The form that matters here is Bacillus subtilis (Various strains).

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What else affects it

Beyond other supplements

Extreme heat processing

Excessive heat may damage spores despite high tolerance

Very high temperatures can destroy spore viability

Artificial preservatives

Some preservatives may reduce spore viability over time

Antimicrobial preservatives can affect beneficial bacteria

Chronic stress

Long-term stress may impair probiotic effectiveness

Stress hormones affect gut microbiome and immune function

How it works

Forms protective spores surviving extreme environmental conditions
Produces multiple digestive enzymes including amylases, proteases, lipases
Secretes nattokinase-like compounds supporting cardiovascular health
Produces antimicrobial compounds inhibiting pathogenic bacteria
Strengthens gut barrier function through beneficial metabolite production
Stimulates immune cell activity and antibody production

Key findings

what the evidence supports

Proven enzyme production capabilities for digestive health
Potential cardiovascular benefits through enzyme pathways
Exceptional survival characteristics in harsh conditions
Good safety profile with minimal adverse effects

Sources: NIH Examine.com · data reviewed 2026-08-01

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of Bacillus subtilis?

Documented effects: Enhanced digestive enzyme production; Improved cardiovascular health support; Strengthened immune system function; Exceptional survival and stability. Produces various digestive enzymes improving nutrient breakdown and absorption

How much Bacillus subtilis should you take per day?

The common daily range is 1-3 billion CFU. By goal — digestive enzymes: 1-3 billion CFU daily with meals; cardiovascular support: 1-3 billion CFU daily with meals; immune support: 1-3 billion CFU daily; gut barrier support: 1-3 billion CFU daily.

When is the best time to take Bacillus subtilis?

With meals daily. First effects are typically reported within 1-2 weeks for initial digestive enzyme improvements.

What are the side effects of Bacillus subtilis?

At excessive doses: Generally safe with minimal adverse effects:, Temporary digestive adjustment during initial supplementation, Very rare bacterial overgrowth in severely immunocompromised, No documented serious adverse effects in healthy individuals, Safe for daily long-term use. Safety rating at normal doses is 9 out of 10.

What should you not take with Bacillus subtilis?

Separate it from Extreme Heat Processing, Artificial Preservatives, Chronic Stress by two to four hours. Excessive heat may damage spores despite high tolerance

Does Bacillus subtilis interact with medications?

Documented interactions with antibiotics, anticoagulant-medications. Discuss these with a pharmacist before combining.

How do you know if you need Bacillus subtilis?

The marker is Digestive enzyme levels, cardiovascular markers, immune markers, optimal range Adequate enzyme levels, healthy cardiovascular function. Common deficiency signs: Digestive enzyme insufficiency symptoms:, Poor digestion and nutrient malabsorption, Digestive discomfort after meals, Compromised cardiovascular function.

Taken for

52 Heart

Fish Oil (EPA/DHA) · EPA · Olive Oil Extract

74 Digestion

Lactase · Lactobacillus acidophilus · Protease