Researchers at the Universidad de la República in Montevideo have published the most comprehensive longitudinal study to date examining the cardiovascular effects of habitual yerba mate consumption. The findings, released in The Lancet Regional Health — Americas, tracked 14,200 adults aged 35 to 70 over a period of 10.5 years, controlling for diet, exercise, smoking status, and genetic predisposition.
The results are striking: participants who consumed yerba mate daily — defined as at least three servings of 250 milliliters — showed a 19 percent reduction in major adverse cardiovascular events compared to non-consumers. The protective effect was dose-dependent, with those drinking five or more servings daily exhibiting up to 27 percent lower risk.
The Polyphenol Mechanism
The research team, led by Dr. Alejandro Ferreiro, identified three primary biochemical pathways through which yerba mate compounds exert their cardioprotective effects. Chlorogenic acid, present in mate at concentrations roughly three times higher than in green tea, was shown to significantly reduce LDL oxidation — a key driver of arterial plaque formation.
Additionally, the saponin compounds unique to Ilex paraguariensis demonstrated potent anti-inflammatory properties, reducing circulating levels of C-reactive protein (CRP) by an average of 14 percent in regular consumers. Elevated CRP is a well-established marker for cardiovascular disease risk.
What makes yerba mate particularly interesting from a pharmacological perspective is the synergistic interaction between its polyphenols, xanthines, and saponins. No single compound accounts for the observed cardiovascular protection — it is the matrix of the whole plant that creates the benefit.
Implications for Global Health Policy
The study's findings arrive at a time when global health authorities are increasingly recognizing the role of dietary polyphenols in chronic disease prevention. The World Health Organization's 2025 dietary guidelines for the first time acknowledged plant-based beverages — including mate, green tea, and hibiscus tea — as potentially beneficial components of a heart-healthy diet.
However, the researchers emphasized several important caveats. The study population consumed mate at traditional temperatures (typically 70-80°C), and previous research has linked very hot beverages — above 65°C — with increased esophageal cancer risk. The team recommended allowing mate to cool slightly before consumption.
Dr. Ferreiro's team is now planning a follow-up intervention study with 3,000 participants in Spain and Portugal to determine whether the cardiovascular benefits translate to populations without a cultural tradition of mate consumption — a critical question for any universal dietary recommendation.