It has been well documented by the elderly generations for the past 100 years that things were different back in their day. And besides technology, if there is any one thing that has changed the most, it might be the sexuality of the young’ins. Even I – at a relatively young age of the upper 20s – am taken aback now and then by the sexual promiscuity displayed by an increasingly young generation.
“Sexting” preteens? Sheesh.
But besides the general moral decline of the country – or perhaps just our indifference for hiding our indiscretions these days – there is a physiological reason behind this trend. Girls are going through puberty at a younger age. In fact, compared to 150 years ago, today’s women begin puberty four years earlier than their classical counterparts.
There could be many reasons for this trend, including genetic traits, living conditions, lifestyle, geographical location and environmental chemicals. One influence, however, that pretty much everyone agrees is a contributing factor, is diet. It stands to reason that with more calories at a younger age, the body has the support needed to start growing and producing babies.
But it is difficult to separate caloric intake from all of the other contributing factors, so definitive proof – or at least the amount to which diet contributes – remains elusive.
It might not be direct evidence for humans, but researchers from the University of Wisconsin recently ran an experiment with female rhesus monkeys that proves an elevated caloric diet early in life directly leads to an early puberty.
Ei Terasawa, Joe Kurian, Ricki Colman, and colleagues from the Wisconsin National Primate Research Center noticed that their monkeys were hitting puberty at an earlier age compared to the 1970s. Since data on first menstruation and body weight has been kept meticulously, they also noticed immediate shifts at points in history where the monkeys’ diets were uniformly increased through an update in standard procedures.
To confirm, the group took eight female monkeys that were born at roughly the same time. They split them into groups so that their ages and weights were basically the same, and then fed four of them a high calorie diet while the other set got a typical fare. Then they watched and waited for the results.
As predicted, the group of monkeys with the high calorie diet hit puberty six to seven months earlier than the others.
The results could be interpreted as support for a theory that puberty begins once an individual hits a certain weight. After a year’s time, the monkeys in both groups weighed roughly the same. However, the high-calorie group grew much quicker and got to that weight much faster than their counterparts. Their growth was accelerated, as was their development into adulthood. Seeing as how both groups had the same living conditions, the same environment, the same everything – these results point directly to the increase intake of calories.
Though the two groups weighed the same, the high-calorie diet group did have more body fat and a higher BMI than the control group. This points to the problem. It might not be the worst thing in the world for women to hit puberty a bit earlier, but the caloric intake that leads to it also leads to metabolic diseases in adulthood, including type II diabetes, obesity, cancer, heart disease and metabolic syndrome.
So besides keeping your daughters healthy, if you’d like to see them become women when the time is right, keep watch to make sure they’re not eating a dozen Krispy Kremes per day.