Berenice Langdon questions probiotic claims, dosages and efficacy
Updated
Updated · ScienceAlert · May 9
Berenice Langdon questions probiotic claims, dosages and efficacy
8 articles · Updated · ScienceAlert · May 9
The St George's, University of London senior lecturer says products sold in pharmacies contain 2bn to 25bn bacteria per capsule, yet make broad gut-health claims without proving benefit.
She argues most ingested bacteria are killed by stomach acid, surviving probiotic strains usually last only days, and high microbial loads may pose infection risks for people with weakened immune systems.
Langdon says brands rely on bacteria long classed as safe, allowing limited research and only qualified health claims, while consumer demand remains strong despite uncertain value and notable cost.
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