7 Surprising things your first period can tell you about your health

6. Bone Density

Surveys of pre- and post-menopausal women reveal that a first period arriving at age 17 or older correlates with lower bone mineral mass and a higher risk of fracture from osteoporosis. (Feel better starting today with Rodale’s The Thyroid Cure, a new book that’s helped thousands of people finally solve the mystery of what’s ailing them.)