Matcha Tea Quality and Functional Effects on Gut Microbiome: A Comprehensive Systematic Review

Recently, matcha tea (MT) -a finely powdered form of green tea- has successfully been emerged in the global beverage market. Among its health-promoting properties, the potential modulatory gut microbiome effect has gained increased attention. MT is consumed as whole leaves, ingesting a broad spectrum of bioactive compounds such as catechins including epigallocatechin gallate (EGCG) and dietary fiber, both of which are known to influence gut microbiota composition. MT quality is based on sensory attributes, reflecting on the balance of catechin to amino acid content. Thus, different MT qualities vary substantially in catechin and therefore in EGCG level. This systematic review aimed to examine the available humans and animals studies, evaluating the functional effects of MT supplementation on gut microbiome. The findings suggest that MT may affect the gut microbiome composition, by promoting the growth of the probiotic bacteria Bifidobacterium, Alloprevotella, Lactobacillus and Akkermansia. In parallel, MT inhibited the growth of potentially harmful bacteria, such as the family Ruminococcaceae and the genus Helicobacter and Clostridium; but alterations in alpha and beta diversity were not consistent. Further research is necessary to correlate MT supplementation, characterized by its bioactive content, with specific gut modulatory effects, while assessing its potential prebiotic activity.