Digestive Enzyme Dosage: Activity Units (FCC, ALU, GalU) Explained

By Erin Rose · Updated July 20, 2026 · Methodology

Educational summary — not medical advice, and not a dosing framework for prescribed pancreatic enzyme replacement therapy. This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

Four unit systems, no cross-category converter

Unlike a vitamin with one settled "mg per day" figure, this category doesn't have one dosing unit at all. U.S. lactase products commonly disclose FCC (Food Chemicals Codex) units or ALU (Acid Lactase Units) — Lactaid Fast Act Caplets (96ct)'s own label copy states roughly 9,000 FCC per caplet, though that figure hasn't been independently re-confirmed against the physical Supplement Facts panel this pass. The clinical trials behind lactase's evidence used yet another convention: Montalto et al. 2005 dosed 3,000–6,000 UI (international units) in its milk-challenge design — a real, additional source of cross-study confusion worth naming plainly, since UI, FCC, and ALU are not the same figures on the same scale. Alpha-galactosidase products disclose GalU (galactosidase units); Di Stefano et al. 2007 tested 300 and 1200 GalU against a bean meal, with 1200 GalU showing the clearer effect — but Beano Extra Strength (100ct) did not have a per-tablet GalU figure confirmed on its listing this pass, a verification gap even on a genuinely evidence-backed product. Broad-spectrum blends skip activity units entirely and disclose only a milligram total for the whole proprietary blend — which tells you almost nothing about actual enzymatic potency, the same trap the site has already documented for bromelain's GDU/MCU/FIP units. Pancreatic enzyme replacement therapy uses USP or Ph.Eur lipase units, formally dose-adjusted by a prescriber to body weight, fat intake, and steatorrhea response — not a consumer-facing number at all.

Timing, by enzyme

Timing is enzyme-specific, and getting it backward is a real, common mistake. Lactase needs to be present in the gut at the same time as the lactose, so take it with the first bite or sip of the dairy food — not 30 minutes before, and not after symptoms start. Alpha-galactosidase needs to be present with the raffinose-family sugars in beans and legumes before they reach the colon, so take it at the start of the meal — taking it after you already feel bloated is much less useful, since the fermentation that causes the gas has likely already begun. Broad-spectrum blends are generally taken with meals per label, consistent with a general digestive-support framing rather than a single trial-proven timing window. Pancreatic enzyme replacement therapy is taken with meals and snacks, at a prescriber-set dose — timing and amount are both part of the medical prescription, not a label instruction to self-adjust.

How to think about dose in this category

• Match the unit system to the enzyme, not the mg. A 620mg broad-spectrum capsule and a 9,000 FCC lactase caplet are not comparable numbers on any shared scale.
• Don't extrapolate one enzyme's dosing rule to another. "With the first bite" (lactase) and "at the start of the meal" (alpha-galactosidase) sound similar but time to different biology — see each product's specific evidence page.
• A milligram-only label on a broad-spectrum blend is itself information. It means you cannot verify true potency from the label — not a reason to assume the product is equivalent to a better-disclosed one.
• Diagnosed EPI symptoms need a prescriber, not a bottle. Persistent fatty, floating, foul-smelling stools or unexplained weight loss are a gastroenterology referral, not a supplement-aisle decision.
• Porcine pancreatin is in some broad-spectrum blends (e.g. NOW Super Enzymes). Check the ingredient list if you avoid pork or have a related allergy.

Frequently asked questions

Related

• Digestive enzymes: what they are & who each one's for
• Best digestive enzymes — ranked within use case
• Lactase for lactose intolerance
• Do digestive enzymes work? — the full honest verdict
• Bromelain dosage guide — the site's original activity-units-vs-mg case study

Sources