Enzyme
Pepsin (Aspergillus niger)
Also known as: fungal pepsin, microbial pepsin, Aspergillus niger pepsin, acid protease
Pepsin is a proteolytic enzyme derived from Aspergillus niger fungus that breaks down proteins in acidic environments, primarily used in digestive support supplements. It is commonly paired with betaine HCl to support gastric protein digestion in individuals with low stomach acid.
Primary uses
- Protein digestion support
- Digestive enzyme replacement
- Hypochlorhydria support (low stomach acid)
How it works
- Proteolytic enzyme that cleaves peptide bonds in acidic pH (optimal pH 1.5-2.5)
- Breaks down dietary proteins into smaller peptides for improved absorption
Dosage
- Typical range
- 100-500 mg per dose
- Timing
- With meals, particularly protein-containing meals
- With food
- Must be taken with food; requires acidic gastric environment to be effective
- Duration
- May be used short-term or as ongoing digestive support; no established maximum duration
- Special populations
- Should not be used by individuals with peptic ulcer disease or severe gastritis without medical supervision
Forms
- Capsule· 70/100
- Tablet· 70/100
Safety
Common side effects
- Generally well-tolerated
- Rare: mild GI discomfort, nausea
Contraindications
- Active peptic ulcer disease
- Severe gastritis or esophagitis
- Allergy to Aspergillus species
Evidence notes
Limited clinical evidence specific to Aspergillus niger-derived pepsin. General enzyme therapy shows modest evidence; fungal pepsin efficacy compared to animal-sourced pepsin is not well-established in RCTs. Most evidence is theoretical or from small studies.
Grade C: Mostly observational or small trials; mechanism is plausible but unproven at scale.
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