A study has found that it is highly likely that cholesterol is the reason why overweight children go through puberty early.
A research team at the University of Copenhagen in Denmark revealed that cholesterol, a type of fat, is the main cause of early puberty in obese children in a fruit fly experiment.
As the number of obese children continues to rise worldwide, children are entering puberty faster and faster. Especially girls. According to one survey, puberty begins an average of three months earlier for every decade since 1977. However, the scientific explanation for this is unclear and no new facts have been revealed. Early puberty can leave children with psychological and social problems and increase their risk of cancer, diabetes, depression and cardiovascular disease later in life.
As a result of experiments with Drosophila, a ‘model organism’ genetically similar to humans, the research team discovered that it could be a major cause of early puberty.
Cholesterol is a type of fat… Obese children have much more cholesterol in their body fat
Professor Kim Lewitz, lead author of the study, said: “Cholesterol is a fat, and if you are overweight, your body fat contains more cholesterol. “Cholesterol levels have been shown to play a key role in the early maturation of fruit flies.” Cholesterol in the adipose tissue of the fruit fly and in certain supporting cells of the brain influences the growth of the fruit fly until it reaches maturity. Drosophila and human body systems are very similar. Cholesterol in adipose tissue may help explain the association between childhood obesity and early puberty.
The research team tested their hypothesis by feeding fruit fly larvae a diet high in cholesterol. It was compared with fruit fly larvae (control group) that were not fed a cholesterol-rich food. The results showed that the cholesterol-fed larvae consistently grew faster and reached puberty sooner. This is the result of cholesterol accumulated in the body fat and support cells of the brain of fruit flies, which released more growth hormone.
When a critical weight is reached, body systems signal the brain center to begin maturation and enter puberty.
During the increase in body weight and fat mass in fruit flies, a signal to start maturation appears at a certain point, that is, at a critical weight. At certain points, the fruit fly’s body system produces steroid hormones that send maturation-encouraging signals to brain centers. This hormone corresponds to human testosterone and estrogen. “Because overweight children have more body fat, they are likely to have stored more cholesterol early in their development,” said Professor Lewich.
The team also showed that cholesterol activates cell growth through the same mechanism, which can lead to cancer. The results of this study (Insulin signaling couples growth and early maturation to cholesterol intake in Drosophila) were published in the international journal Current Biology.