Good Home-Cooked Meals Can Wreck Family Life

How can that be?  A good diet helps people grow taller and mature sexually earlier too.  In past centuries raging hormones didn't get an upper hand until a youngster was well into their teens and had been working as an adult, often for their parents.  It was easier for parents to have control.  Youngsters who engage in sex while going to high school will not be ruled readily.  Centrifugal forces that tend to break up the family or at the very least make it hard to govern, will prevail.

The Chess Game, Anguissola 1555
He painted his sisters. The charming
young adult on the left is flat chested.

Over the past century the age at menarche [first menstruation] has fallen in industrialized countries, but that trend has stopped and may even be reversing. The average age at menarche in 1840 was 16.5 years, now it is 13.

In seventeenth century Austria, the well-fed upper classes had children well ahead of the country folk.

According to Shorter's research, by the 17th century — the end of the Renaissance era — the average age of first period had risen to 16. Shorter attributes this to widespread malnutrition in the era; Renaissance girls who were underfed typically went into a state of delayed puberty. He also notes a class divide among the age of first period, quoting an anonymous Austrian author in 1610 who claimed that, "The peasant girls of this Country in general menstruate much later than the daughters of the townsfolk or the aristocracy...The townsfolk have usually born several children before the peasant girls have yet menstruated."

Menarche trending in Norway

It's complicated, however.  There's evidence that before the crowded city times of the industrial revolution, menarche was at an earlier age.  Also, puberty is a larger event over quite a few years and the one can be early while the other may take years to complete.  Lastly, menarche is easier to report about because young men producing viable sperm don't have an easy to detect event.