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Many people seem to think so. In a survey of 2,557 British adults, roughly 35 percent of those with—versus 10 percent of those without—constipation reported taking probiotics. And a majority assumed that probiotics had curbed constipation in scientific studies.

Surprise! Most haven’t.

“There are a lot of claims out there for probiotics and regularity without studies to back them up,” says Jacqueline Wolf, a gastroenterologist and associate professor of medicine at Beth Israel Deaconess Medical Center in Boston.

Few probiotics have been tested for regularity in more than one study.

“The studies are often very small and poor quality, so it’s hard to draw conclusions,” says Lucinda Harris, a gastroenterologist and associate professor of medicine at the Mayo Clinic in Scottsdale, Arizona.

Here’s what the best studies have found.

Even though all of these studies were company funded, none had impressive results:

Bifidobacterium lactis DN-173 010.(In Activia yogurt.) Among 126 Chinese women who reported having fewer than three bowel movements per week, those who ate yogurt with 12.5 billion CFU (colony-forming units) daily for two weeks had softer stools and averaged 1½ more bowel movements during the second week than the placebo eaters.

Bifidobacterium lactis BB-12.(In Nancy’s yogurt, Good Belly Probiotics bars and cereal, etc.) In 1,248 Europeans who reported having two to four bowel movements per week, those who took either 1 or 10 billion CFUs a day for four weeks had no more bowel movements than placebo takers.

Bifidobacterium lactis HN019. (In Tropicana Essentials Probiotics drinks, Kellogg’s Happy Inside cereals, etc.) Among 228 French adults with constipation, those who took 1 billion or 10 billion CFU a day for four weeks had no more bowel movements and their stools were no softer than placebo takers.


Photo: Kateryna_Kon/stock.adobe.com.