Lactase enzyme and lactose intolerance
What 5 graded rows on lactase enzyme agree on for lactose intolerance, and where they differ. Counted side by side, never averaged.
Consensus finder Rows from the Lactase enzyme page, reviewed Oct 21, 2026 How it decides
What the rows agree on
Each block and row is one graded row from the Lactase enzyme page, with its PubMed record.
Your question
Lactase enzyme and lactose intolerance
5 rows · 228 peopleMostly an improvement: 4 of 5 rows, and most of the people. 1 had mixed results.
- CGrade C× 5
- Rows
- 5
- Trials
- 5
- People
- 228
What the rows share
From the rowsThe best-graded row, grade C, is a crossover trial of 67 people (2022) and reported mixed results.
The rows run from 24 to 67 people, published from 1992 to 2022: 5 single studies.
The rows
4 improved · 1 mixed- CGrade CBreath-test normalisation, peak breath hydrogen and symptom score · Improved
RCT · n 60 · 2010 · Lactose-intolerant patients
Tilactase 15 minutes before the breath test · Single dose
More patients normalised their breath test with tilactase than placebo, and peak hydrogen and symptoms fell; tilactase outperformed L. reuteri.
Row on the Lactase enzyme page · PubMed 20391953 (opens PubMed)
- CGrade CBreath hydrogen and symptoms after a 25 g lactose load · Improved
Crossover RCT · n 47 · 2021 · Adults with breath-test-confirmed lactose intolerance (India)
3 tablets (13,500 FCC) 5 minutes before 25 g lactose · Single dose per visit, 1-week washout
Symptom scores and breath hydrogen were lower with lactase than placebo; cumulative breath hydrogen over 3 hours fell by 55%.
Row on the Lactase enzyme page · PubMed 33490624 (opens PubMed)
- CGrade CBreath hydrogen and symptom score after 400 mL milk · Improved
Crossover RCT · n 30 · 2005 · Adults with lactose malabsorption and intolerance
3,000 units added 10 hours before, or 6,000 units 5 minutes before, drinking 400 mL milk · Single test per condition
Both regimens cut peak breath hydrogen (about 12–14 vs 51 ppm with placebo) and cumulative hydrogen, and lowered the symptom score.
Row on the Lactase enzyme page · PubMed 15674309 (opens PubMed)
- CGrade CBreath hydrogen and symptoms after 50 g lactose in milk · Improved
Crossover RCT · n 24 · 1992 · Lactose-intolerant adults
3 tablets (9,900 FCC units) with 50 g lactose · Single dose per visit, ≥1-week washout
Peak breath hydrogen was lower and cramping, belching, flatulence and diarrhoea were rated less severe in the first 8 hours than with placebo.
Row on the Lactase enzyme page · PubMed 1534729 (opens PubMed)
- CGrade CBreath hydrogen and symptoms after 25 g lactose · Mixed
Crossover RCT, 2 studies · n 67 · 2022 · Adults with lactose intolerance in two crossover trials (lactose in fat-free milk, or in water)
4,662 FCC units taken with 25 g lactose · Single dose per visit, 1-week washouts
Lactase lowered breath hydrogen versus placebo in the milk-challenge trial (ratio 0.190) but not significantly in the lactose-solution trial (ratio 0.493). In the milk trial it also lowered the odds of abdominal pain and flatulence. The probiotic (Bi-07) lowered breath hydrogen versus placebo in both trials and was non-inferior to lactase in the lactose-solution trial, but raised the odds of nausea there.
Row on the Lactase enzyme page · PubMed 36149331 (opens PubMed)