Klein · Journal of the American College of Nutrition 2011 · randomized controlled trial · n=58

Mate tea (Ilex paraguariensis) improves glycemic and lipid profiles of type 2 diabetes and pre-diabetes individuals: a pilot study.

Level 2 - randomized trial

Individual randomized controlled trial

PubMed 22081618 · doi:10.1080/07315724.2011.10719975 · record verified 2026-08-26

What was done

A 60-day pilot randomized controlled trial evaluated roasted mate tea (Ilex paraguariensis) with or without dietary intervention in 58 participants (29 with type 2 diabetes mellitus [T2DM] and 29 with pre-diabetes). Participants in each diagnostic group were divided into three arms: mate tea alone (330 mL three times daily), dietary intervention alone, or mate tea combined with dietary intervention. Blood samples and dietary intake were assessed at baseline and after 20, 40, and 60 days.

What was found

In T2DM subjects, mate tea significantly decreased fasting glucose by 25.0 mg/dL, HbA1c by 0.85%, and LDL-c by 13.5 mg/dL (p < 0.05), with no significant changes in baseline macronutrient intake. In pre-diabetes subjects receiving mate tea combined with dietary counseling, LDL-c decreased by 11 mg/dL, non-HDL-c by 21.5 mg/dL, and triglycerides by 53.0 mg/dL (p < 0.05); this group also had significant dietary changes, including reduced total fat (-14%), cholesterol (-28%), saturated fat (-23.8%), and monounsaturated fat (-28.0%), and increased fiber (+35%) (p < 0.05).

Why it matters

This study suggests that roasted yerba mate tea may modestly improve glycemic and lipid parameters in individuals with type 2 diabetes or pre-diabetes.

Limits

The study was a small pilot trial (58 participants split across six sub-arms), lacked a placebo or blinded control beverage, and had a short duration of 60 days. In pre-diabetic subjects, the lipid benefits were confounded by concurrent dietary modifications.

Cited by