Has it really been shown that green tea makes your first period come sooner?

Your body needs: To be ready to start having periods. Usually you need at least 17% body fat. The ovaries need to be able to secrete estrogen. The estrogen eventually stimulates growth of the endometrium (uterine lining) which is eventually shed. There aren't studies at this time that support use of green tea to induce menses. A 2010 study showed that japanese females who drank > 5 cups green tea/day had first.