Scientists compared the saliva of 13 nicotine pouch users with 15 non-users. Choline stood out.
A preliminary NMR metabolomics study from the University of Eastern Finland found elevated salivary choline in nicotine pouch users and flagged six altered metabolic pathways. Small, cross-sectional, and explicitly preliminary — but one of the first looks at pouch users’ saliva chemistry.
A team at the University of Eastern Finland has published one of the first metabolomics studies of nicotine pouch users' saliva, and the headline finding is a single molecule: choline. Salivary choline was elevated in pouch users compared with people who use no nicotine products at all. The study appeared in Nicotine & Tobacco Research on 6 October 2026, and its authors are careful to call it preliminary.
What the study did
Researchers in Kuopio recruited 28 people: 13 nicotine pouch users and 15 controls who use no nicotine products. They collected whole-mouth saliva three ways from each participant — unstimulated, sub-pressure stimulated, and stimulated — then ran the samples through nuclear magnetic resonance (NMR) spectroscopy and mapped the results with the MetaboAnalyst 6.0 pathway-analysis platform.
What they found
- 35 salivary metabolites were quantified across the samples.
- Choline was elevated in pouch users in both unstimulated and stimulated saliva, the one metabolite the authors single out as different from controls.
- Pathway analysis flagged six metabolic pathways as altered in pouch users, with phosphatidylethanolamine biosynthesis showing the highest pathway impact score, followed by the glucose-alanine cycle and phosphatidylcholine biosynthesis.
The authors' interpretation: elevated choline may reflect effects on the cholinergic system (the signalling system nicotine acts on), and disruption of phosphatidylethanolamine metabolism could in theory relate to salivary gland function — reduced saliva secretion and altered composition have been linked to that pathway in earlier literature. That second step is a hypothesis in a discussion section, not a demonstrated outcome in this data.
What it can and cannot tell you
- It is a preliminary study by design. 13 users versus 15 controls is a small sample, and the authors state plainly that more studies are needed.
- No causality claim is possible. The design is cross-sectional: it compares two groups at one point in time. It cannot show that pouches caused the metabolite differences, only that the differences were present.
- "Altered metabolites" is not a disease finding. No clinical outcomes were measured. The paper reports chemistry, not diagnoses.
- The authors also note limitations of their own: a more detailed characterization of different product use could have improved the nicotine-intake models.
Why it matters
Most pouch research so far has looked at the mouth's surfaces — lesions, gum recession, peroxide. This study looks at the chemistry of saliva itself, which is a different lens on the same question: what happens in the oral environment when someone uses pouches daily. If larger studies reproduce the choline and phosphatidylethanolamine signals, they give researchers concrete biomarkers to track — including, as the authors suggest, whether those markers normalize after stopping. Until then, this is a signal to be followed up, not a verdict.
Nicotine strength is the variable users control most directly, and PouchFinder lists the strength range for each major brand.