Does Beano Prevent Gas? A Double-Blind Crossover Study of Oral Alpha-Galactosidase to Treat Dietary Oligosaccharide Intolerance

J Fam Pract. 1994 Nov;39(5):441-5.


Background: Beano, an over-the-counter oral solution of alpha-galactosidase, is used to prevent flatus and other gastrointestinal symptoms resulting from a high-fiber diet. The efficacy of this product, however, has not yet been adequately evaluated.

Methods: Nineteen subjects were randomized into two groups and fed test meals of meatless chili. At the first test meal, group 1 received eight drops of alpha-galactosidase solution and group 2 received eight drops of placebo. After the meal, subjects were asked to keep a careful record of gastrointestinal symptoms, including occurrences of intestinal gas passage, for the next 6 hours. One week later, an identical test meal was served to each study subject and the solutions were reversed. Again subjects recorded their symptoms for the next 6 hours. Data were analyzed by means of paired t tests.

Results: The number of flatulence events per hour was significantly less in the group treated with alpha-galactosidase than placebo over the 6-hour follow-up period (F = 2.87, P = .016). When the two groups were compared at each follow-up interval, this difference was statistically significant only for the 5th hour after ingesting the test meal (t = 2.19, P = .04). No differences between the two groups were found in the extent of bloating or pain following the meal.

Conclusions: Oral alpha-galactosidase solution is efficacious, at least in some patients, for the prophylaxis of gastrointestinal intolerance of oligosaccharides.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Cross-Over Studies
  • Dietary Fiber / adverse effects
  • Double-Blind Method
  • Fabaceae / adverse effects*
  • Fabaceae / chemistry
  • Female
  • Flatulence / etiology
  • Flatulence / prevention & control*
  • Humans
  • Male
  • Oligosaccharides / adverse effects*
  • Oligosaccharides / analysis
  • Pilot Projects
  • Plants, Medicinal*
  • Prospective Studies
  • Solutions
  • alpha-Galactosidase / therapeutic use*


  • Dietary Fiber
  • Oligosaccharides
  • Solutions
  • alpha-Galactosidase