Why do you get headaches after drinking yerba mate?

the caffeine can irritate your liver. that's why I get a headache when I drink yerba mate.

But like other caffeine-rich infusion, such as coffee and tea, mate is generally recognized as safe by the United States Food and Drug Administration.

Mate tea contains several vitamins and minerals important to human health, including vitamins A (as beta-carotene), B1, B2, C and E, as well as phosphorus, iron and calcium. You can also find more information here: http://comex.lasmarias.com.ar/eng/home.php