Most 'Probiotic' Foods Aren't Actually Probiotic | Dr Maria Marco

The word gut health is on almost everything now, from yoghurt lids to supplement labels. So I asked food microbiologist Dr Maria Marco, Professor at UC Davis and President of the International Scientific Association for Probiotics and Prebiotics, what it actually means. She spent a year with a panel of clinicians, dieticians, and immunologists trying to define it, and the most striking finding was how much we still cannot measure.
This is a conversation about the distance between the science and the marketing, and it includes some claims that will change how you read a label.
What we cover
The consensus definition of gut health, and why symptoms and pathology can point in opposite directions
Whether commercial microbiome stool tests and diversity scores mean anything clinically
Why sauerkraut sold as probiotic is, in Maria's words, "just a marketing thing"
Whether the microbes in yoghurt survive digestion, colonise your gut, or simply pass through
Why dead and pasteurised microbes may still be beneficial
How to choose a probiotic that has actually been tested in people, and when to stop taking one
Maria is unusually willing to say what we do not yet know, and in a field this commercially crowded, that honesty is worth a great deal.
To connect with Dr Maria Marco, visit the Marco Lab at UC Davis, find her on LinkedIn, or follow her lab's work on Instagram at @eat.lac.project.
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