Hereditary factors in childhood obesity

Considering hereditary causes of childhood obesity means that, if both parents are obese, the child has better chances of obesity too, compared with those people that both parents are lean.

Is heredity more important?
Genetics may have a greater contribution in childhood obesity than people previously thought. New studies estimate that the effect of genes account for 90-95 percent of the percent body fat (PBF) in children, while the remaining 5-10 percent is attributed to learned the behavior.

While there is general acceptance that hereditary conditions might incline to human obesity, it is often assumed that such factors would affect metabolic rate or the selective transforming of surplus of calories into fat.

Genetic factors are engaged in the regulation of child body weight and in determining individual reactions to environmental factors such as food, rest and exercise. Scientists have discovered a close connection between levels of leptin, a protein which controls appetite and the rate at which calories are burned, and the body fat. That means leptin is an important regulator of energy balance in humans, helping the body to keep its weight stable. As in many obese children tests have revealed very low levels of blood leptin, there are opinion that obesity, especially its severe forms, could be treated by correcting this congenital leptin deficiency.

Is learned behavior more important?
There are also and contraire opinions suggesting that leptin could not be a cure for the overweight. They are partly linked with studies of adopted children revealing that learned eating and activity behavior are more important that genetic inheritance.

On the other hand, a common observation reveals that most obese people have put on weight because they eat too much and exercise too little, despite of fact they have a normal level of leptin.

Conclusions
Accepting that genetic predisposition may offer a support in effective treating childhood and adolescent obesity, the scientists suggest that future studies must target the identifying the critical life experiences that may lead to adiposity condition in children and adolescents.

To conclude, the most evidence we have suggests that the major influence of genes on human obesity is just as likely (or perhaps more likely) to directly impact on hunger, satiety and food intake rather than metabolic calories-fat rate transforming. At the risk of oversimplification, the widespread acceptance from genetic point of view, is that childhood obesity appears to be less a metabolic than a neuro-behavioral condition.

In simple words, most people put on weight and become obese because of environmental factors, such as diet and lifestyle.