I suspect that another key factor stimulating earlier menarche and diminishing anovulatory cycles has been the authorities’ recognition of the importance of iron in the diet of females. Iron-fortified foods consumed by children and teenagers, along with a consistently high meat diet, have increased their young bodies’ iron stores. This increase, combined with adequate stores of fat, has signaled the feedback controls in the brains of these young girls that it is now permissible for pregnancy to proceed.
Role of Iron
