Endocrine-disrupting substances, obesity, and fatherlessness could all be factors.
Puberty is occurring earlier than it did even in the 1970s, according to a recent 2020 review that looked at 30 studies.
The study was based on a seminal study conducted in 1997 and published in the journal Pediatrics by Marcia Herman-Giddens, which made the pattern known to the medical world.
Puberty is undoubtedly starting younger than in past generations, according to studies, although the exact cause is still a little unclear to researchers.
“There’s definitely an association with obesity, but that is not the only thing — and my own opinion is that it will never be entirely figured out because there’s no way to separate the endocrine disrupters, the lack of activity in today’s children, the junk food, and, the increasing obesity and so many other factors,” Herman-Giddens said. “The absence of fathers, for example… there have also been studies that have shown earlier puberty in households without biological fathers.”
“The age at which girls are reaching puberty has been trending downward in recent decades, but much of the attention has focused on increased body weight as the primary culprit,” said study lead author Julianna Deardorf at the time. “While overweight and obesity alter the timing of girls’ puberty, those factors don’t explain all of the variance in pubertal timing. The results from our study suggest that familial and contextual factors — independent of body mass index — have an important effect on girls’ pubertal timing.”
In a study released in 2010, scientists at the University of California-School Berkeley’s of Public Health discovered that young girls’ quicker development of breast and pubic hair was predicted by the presence or absence of a biological father in the family.
However, the consensus among researchers is that there is a direct link between obesity and earlier times.
Researchers discovered a substantial correlation between pre-menarcheal body mass index (BMI) and a higher risk of early menarche in a 2003 study of over 1,200 Louisianan girls. Researchers have more recently claimed that a greater BMI has an impact on earlier puberty.
A function for endocrine disruptors like BPA and phthalates is also possible. They are known to interfere with human hormones because they can connect to a receptor in a cell and then inhibit the proper hormone from binding. These can be found in our food, water, and many other home products.
According to one study, early puberty may be caused by endocrine disruptor exposure even before birth.
“The effects of these chemicals are very complex,” Dr. Luz Claudio of the Icahn School of Medicine at Mount Sinai in New York City told Reuters in 2018. “Their effects on the hormonal system is different with different chemicals, they have different potencies, their effects can be modulated by other factors such as genetic predisposition, and importantly, their effects can be different depending on the timing of the exposure.”
Because it’s so difficult to identify a group that hasn’t been exposed to endocrine disruptors, according to Herman-Giddens, it can be challenging to determine their genuine effects.
“You cannot get a population of girls that are not affected … endocrine disruptor chemicals are in our bodies, they’re in polar bears in the North Pole, all over the world,” Herman-Giddens said. “You can’t find a clean population that you could compare with one that’s been exposed, and you would have to follow them for years, and there’s so much to control — diet activity, exercise — it’s impossible.”
Herman-Giddens described it as a tremendous worry. Because, among other things, early puberty means more oestrogen is exposed to the body, which increases the risk of cancer. Additionally, it shortens childhood, causing the brain to grow later than physical maturity.
However, there are reasons for researchers to continue working on their studies since there are worries about what this means for future generations of youngsters.
Parvathy Sukumaran 
