Please review my IELTS essay.

Childhood obesity is becoming a serious problem in many countries. Explain the main causes and effects of this problem.
My essay :
The increase in childhood obesity is getting one of the most pressing problems in many countries. The main causes and effects will be analysed in my essay.
First of all, unhealthy eating habit is the key factor which makes everyone obese. Children seem to be into consuming a lot of favourite foods such as sugary snacks, chips when having leisure time or days-off at home. At school, because of having a little time to relax, they usually tend to eat fast food like hamburgers, KFCs, sanwiches. All these habits make children overweight rapidly. Another factor which also contributes to children's plumpness is sedentary lifestyle. In fact, the more children spend time sleeping, the lazier they become. Moreover, they are glued to TV preferable programs all the time. To make it worse, they rarely move around and help parents do domestic chores. Furthermore, during break times at school, they always keep in their positions instead of engaging in outdoor activities, playing games or team sports with peers.
Second, we need to thoroughly understand its consequences and avoid it as soon as possible. The most serious effect is children health. Being overweight causes substantial risks such as cardiovascular diseasesss, heart attack, high blood pressure. What's more, obesity can also affect their future career. There is no specific evidence that obese people receive less attention then ordinary individuals, however, apparently some jobs often take priority over those who have fit bodies. Last but not least, many people usually behave badly towards overweight kids. The fatter children are, the more they are bullied by other kids. Therefore, they appear to have fewer close friends than others.
To conclude, "health is wealth". Having a proper diet and getting much exercise regularly can help to decrease in obesity. Those who do not find time for regular workouts will end up in hospitals.