Dannon markets its Activia line of yogurt by claiming that it influences intestinal transit time -- that is, how fast food scoots through your bowels toward elimination. In doing so, Dannon is drawing upon the popularity of functional foods -- those that confer health benefits above and beyond basic nutrition.
Yogurt and Probiotics
Activia, like all yogurts, is created by using bacteria to ferment milk. In yogurt and other foods that are fermented, these bacteria sometimes remain alive even after consumption and deliver a variety of positive health effects, such as prevention and treatment of diarrhea, Crohn's disease and ulcers caused by Helicobacter pylori infection. The bacterial cultures in yogurt have been called "probiotic," which refers to microbes that benefit human health when consumed live.
Activia's Probiotics
The probiotic bacteria in Activia are a specific type that is not found in any other bacteria, but that doesn't necessarily mean that they're somehow superior to other yogurt cultures. Probiotic microbes have existed in yogurt for as long as yogurt has been around, and they are not unique to the Activia brand. Activia yogurt contains a type of probiotic microbe that Dannon calls Bifidus Regularis. The true scientific name of this bacterial strain is Bifidobacterium animalis strain 172-010, according to the Supermarket Savvy website. It is important to keep in mind that probiotics are "strain specific," meaning that different types have different health benefits.
Activia and Constipation
Dannon's website stops short of claiming that Activia prevents constipation, noting that Activia has not been studied "in the pathological context of constipation." In healthy adults, Activia has been noted to cause food to pass through the intestines faster. Dannon explains that the effects of shorter intestinal transit time after consuming Activia were observed in adults who exhibited slower intestinal transit times that fell more or less within normal ranges.
Research
There has not been a lot of independent research to verify the claims regarding the effectiveness of Bifidobacterium animalis in relieving constipation, possibly because this particular probiotic strain is trademarked and only Dannon can profit from any positive findings of such research. The NYU Langone Medical Center notes that Bifidobacterium animalis was found to be effective in relieving constipation in a study involving 266 women. A separate study involving 274 people with constipation related to irritable bowel syndrome found that Bifidobacterium animalis decreased discomfort and increased the frequency of defecation. These effects are not unique to Activia, however. Other probiotics, such as Lactobacillus rhamnosus, have been found to deliver similar effects.
