Early puberty is associated with high risk of obesity for women

Study strengthen existing evidence of a link between the onset of puberty and a woman’s body mass in adulthood.

Obesity women
Obesity women © Imperial College London.

According to the latest finding by the Imperial College London, girls who begin puberty prior will probably be overweight as grown-ups. The study fortifies existing confirmation of a connection between the beginning of puberty and a lady’s weight in adulthood.

Many studies associated obesity and puberty as a risk factor for girls starting puberty earlier. But this study makes it difficult to determine whether early puberty or some other factors are the cause.

The study suggests puberty is itself a risk factor for being overweight, with girls who have their first period earlier more likely to have a higher Body Mass Index (BMI). It could aid untangle complex external factors and add insight into an underlying causal link, showing that early puberty has a significant impact on a woman’s risk of obesity.

Scientists used genetic variants as a tool to look at the effect of the onset of puberty (known as age at menarche), measured as the age of a girl’s first period. The qualities in each cell of our bodies are arbitrarily skilled to us from our folks when their sperm and egg cells combine, with the result of this arbitrary clutter being the hereditary premise of the developing life – affecting everything from hair shading to danger of infection for whatever is left of your life.

In any case, single ‘letter’ changes to the DNA succession of a quality can modify its capacity. As far as sickness chance, these single-letter variations (called single-nucleotide polymorphisms, or SNPs) can bring about a little increment or reduction in a hazard. The mix of variations of in excess of 20,000 qualities contribute towards our total hereditary hazard.

Scientists also used  Mendelian Randomization technique as a tool to show the causal relationship between earlier puberty and increased BMI. They gathered the data from 82,416 women they identified 122 genetic variants that were strongly associated with the onset of puberty – with the women’s age at first period obtained via questionnaire.

Scientists observed the data from the UK Biobank, which holds biomedical data on countless individuals, joining physiological estimation information with hereditary arrangement information and survey reactions.

In particular, they searched for the impact of the hereditary variations identified with age at menarche with BMI in a moment set of 80,465 ladies from the UK Biobank, for whom they likewise had estimations for BMI.

Starting investigation uncovered a connection between these hereditary variations and BMI, with those ladies who had variations related to before pubescence having an expanded BMI. The scientists at that point tried for this same relationship in a third gathering 70,962 ladies, finding a similar affiliation.

Dr Gill, added: “Some of these genetic variants are associated with earlier puberty and some with later onset, so by taking advantage of this we were able to investigate any association of age at menarche with BMI in adulthood.

“We’re not saying that it’s a genetic effect, but rather that by using these genetic variants as a proxy for earlier puberty, we are able to show the effect of earlier puberty without the impact of external factors that might confound our analysis.

“We performed a range of statistical sensitivity analyses to test the robustness of our findings and they remained strong through this, so within the limitations of the study design, we are confident of findings.”

According to the researchers, it remains unclear how maturing earlier has a direct impact on body weight, but they indicate that differences between physical and emotional maturity may play a role.

It could be those young women who mature earlier than their peers are treated differently or have different societal pressures than girls of the same age who have not started puberty.

“It is difficult to say that changing someone’s age of puberty will affect their adult risk of obesity and whether it is something that we can clinically apply – as it would unlikely be ethically appropriate to accelerate or delay the rate of puberty to affect BMI,” added Dr. Gill.

“But it is useful for us to be aware that it’s a causal factor– girls who reach puberty earlier may be more likely to be overweight when they are older.”

Age at menarche and adult body mass index: a Mendelian randomization study’ by Dipender Gill et al, is published in the International Journal of Obesity.