The age at which puberty starts varies quite a bit in girls but the average normally occurs between 11 and 14 years of age. If a girl reaches a particular weight (around 45 kg or 100 lb), the onset of puberty is triggered so that the heavier the child, the earlier puberty occurs, possibly affecting risk of later disease.
With the changes in diet over the last 20 years with so many young girls having a high fat and high sugar diet through junk food this goes some way to explaining why so many are starting puberty younger than expected but the fact it is directly related to their weight may be news to them.
The study was a collaborative effort by the international ReproGen consortium, which included 175 scientists from 104 worldwide institutions, including Boston University School of Medicine (BUSM) and King’s College London.
When menstruation starts is when a girl’s reproductive life begins and it is very much dependent on her nutritional status. Early menstruation is not a good thing as it is associated with many health problems later in life, including breast cancer, endometrial cancer, obesity, type 2 diabetes and cardiovascular disease, as well as shorter adult stature.
The study found genes involved in hormone regulation, cell development and other biological pathways associated with mechanisms age at menstruation which shows that the timing of puberty is controlled by a complex range of biological processes,” said senior author Joanne Murabito, MD ScM, an associate professor of medicine at Boston University School of Medicine and Clinic Director and Investigator of the Framingham Heart Study.
What it is important to understand is that these ‘genetic factors’ can be modified by changes in lifestyle, principally making efforts to reduce or prevent childhood obesity. However, as a large number of teenage girls are also weight obsessed in our celebrity-thin culture it is important to strike a balance between a healthy weight and an abnormal none – whether that is over or under the norm.