Polyphenols, a diverse group of naturally occurring compounds found in plants such as fruits, vegetables, tea, coffee, and cocoa, have shown some scientific basis for supporting gut health and potentially alleviating constipation in adults. The proposed mechanisms include polyphenols' modulatory effects on gut microbiota composition, stimulation of short-chain fatty acid (SCFA) production, and enhancement of intestinal motility. Several studies have suggested that polyphenol-rich foods, such as prunes (which are high in phenolic compounds like chlorogenic acids), may improve stool frequency and consistency, likely due to both their fiber and polyphenol content.

For example, randomized controlled trials have shown that regular consumption of prunes can increase bowel movements in individuals with constipation, and polyphenols may contribute to this effect by altering the gut microbial environment and promoting the growth of beneficial bacteria such as Bifidobacterium and Lactobacillus. Other polyphenol-rich foods, such as kiwifruit and certain berries, have also been studied with similar, albeit modest, benefits.

However, most of the evidence remains preliminary, with limited studies directly isolating the role of polyphenols (rather than fiber or other components) in relieving constipation. Overall, while there is some scientific rationale and early evidence, it is not robust enough to warrant a strong recommendation for polyphenols as a primary treatment for constipation.