Probiotics & Digestion Guides

Digestive supplements use three unrelated measurement systems on the same shelf, which is why they resist casual comparison. Probiotics are dosed in CFU — colony forming units, usually stated in billions — and identified by genus, species and strain. Enzyme products are dosed in activity units such as FCC, HUT and DU, which do not convert to milligrams or to each other. Fibre is dosed in grams.

For probiotics, three details on the back panel separate products: the named strains, whether the CFU count is guaranteed at expiry or only at manufacture, and whether refrigeration is required. That second point is the one most often missed, and the difference between the two claims can be substantial. A large CFU number of unnamed strains is not obviously better than a smaller count of well-characterised ones.

For fibre, the source — psyllium, inulin, methylcellulose, wheat dextrin or acacia — changes both the gram dose and how the product behaves when mixed. Capsule versions need many units to match a single powder scoop, so cost per gram diverges sharply between formats.

These guides cover each unit type and how to read it. To compare products, the probiotics and digestion comparison filters by brand, strength, format and pack size.