Probiotics - do bacteria survive in people's digestive system?

Main Category: Nutrition / Diet
Article Date: 22 Mar 2005 - 11:00 PDT


Research to find out whether bacteria from probiotic products survive in people's digestive systems has been published today by the Food Standards Agency, UK.

The study was designed to find out if and where these bacteria break down as they pass through the digestive system. The study did not look at whether probiotic products have an effect on health.

Findings suggests that not all strains of bacteria used in probiotic products survive through the entire digestive system, although at least one strain in each of the products tested survived beyond the stomach. The research does not show if or where probiotics might have an effect.

Scientists at the University of Reading used laboratory models of the human gut to imitate the conditions of the stomach, upper intestine and lower intestine.

Probiotic bacteria found in 11 different probiotic products were tested. Products included dairy and fruit juice containing live bacteria and dry preparations in the form of tablets, capsules and powder. All bacteria used were grown and their numbers standardised before each experiment began.

The researchers used a model to simulate the effect adding probiotic bacteria would have on the total number of bacteria in a typical human digestive system. Overall, adding bacteria from probiotics did not change the total number of bacteria in the gut.

Probiotic effects in the human gut: Final technical report
pdf file

Probiotic effects in the human gut: Report figures
Microsoft Excel spreadsheet

Probiotic effects in the human gut: Report tables
Microsoft Excel spreadsheet

Food Standards Agency, UK

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