Our science
How do plant extracts and fibres interact with the gut? Explore the human studies, the useful findings and the questions still open.
Selected primary sources checked 15 September 2026. This is an evidence guide, not medical advice or regulatory approval.
Short, uncontrolled human intervention
A four-day cranberry-extract intervention examined stool microbiota in 28 participants and reported changes including a bifidogenic response.
No placebo arm; short duration; a specific extract containing oligosaccharides. Not a trial of Vekovia.
Lessard-Lord et al. · npj Biofilms and Microbiomes · 2024
Open primary sourcePlacebo-controlled human study
A long-term cranberry study in women with recurrent urinary tract infections reported limited effects on the gut microbiome.
A different preparation and population. Neither the positive nor the limited result can be transferred wholesale to another product.
Straub et al. · BMC Microbiology · 2021
Open primary sourceEight-week randomised diet trial
A Mediterranean-diet trial reported an increase in faecal Akkermansia alongside other measured changes.
This was a dietary-pattern study, not a PHGG, inulin or Vekovia trial. It cannot isolate an individual ingredient’s effect.
Tagliamonte et al. · European Journal of Nutrition · 2021
Open primary sourceEU authorised-claim conditions
The bowel-function claim concerns specified native chicory inulin at 12 g daily. The material must meet the regulation’s composition and chain-length requirements.
An ingredient name alone is not proof of eligibility. Microbiome Powder’s supplier specification is pending; the 9 g in Metabolic Powder does not meet the 12 g condition.
Commission Regulation (EU) 2015/2314
Open primary sourceEU authorised-claim conditions
The weight-loss claim requires 3 g daily in three 1 g doses, with 1–2 glasses of water before meals, within an energy-restricted diet. Each quantified portion must contain 1 g.
A choking warning and plentiful water are essential, especially with swallowing difficulties or insufficient fluid. The finished powder portion weight still needs confirmation. This is not an appetite-suppression claim.
Commission Regulation (EU) 432/2012 · Annex
Open primary sourceScientific consensus definition
The ISAPP definition centres on preparations of inanimate microorganisms or their components with demonstrated benefit, rather than simply any molecule produced by microbes.
We use ‘microbial metabolites’ for short-chain fatty acids in educational copy. None of the four formulas is presented as a postbiotic preparation.
Salminen et al. · Nature Reviews Gastroenterology & Hepatology · 2021
Open primary source