Around 13 million children aged between 2 to 19 are obese in the United States alone, with the levels of this condition rising each year. Obese children are more likely to have high blood pressure, type 2 diabetes and high cholesterol. The Centres for Disease Control and Prevention also reported that obese children and adolescents have a higher risk of psychological and social issues, such as discrimination and low self-esteem – this can carry on long into adulthood. To add further to these risk factors, studies have shown that childhood obesity could disrupt the age at which children reach puberty, leading to diminished ability to reproduce. This is particularly the case amongst females.
Both ends of the spectrum, whether it’s anorexia or obesity, can lead to problems with the reproductive organs. In terms of evolution, obesity is a fairly recent addition to health issues – nutritional status is vital to reproduction, and metabolic syndromes caused by obesity can affect one’s reproductive capacity. Researchers have stated that further studies are needed in order to look into the overall impact of obesity where puberty is concerned. It appears to start earlier in girls, and this is being accelerated as the years go on. This could have a number of effects, according to scientists.
One theory is the impact on kisspeptin, which is a recently characterised neurohormone which is vital for reproduction. It’s also thought that the effect on pubertal timing could be the disruption of circadian clocks, which reflect the natural rhythms of the day and night. Disruption of sleep-wake cycles can lead to an effect on the secretion of hormones such as cortisol, testosterone and insulin – one result of this is the impact on the reproductive cycle. Researchers claim that excess fat could also be contributing to the rates of infertility and reproductive diseases, such as increasing the risk of reproductive cancers and metabolic syndrome.