In my opinion, dieting could be very harmful. Dieting has as many opponents as followers. Both these group have a lot of arguments reasons forward and against dieting. There are a lot of people, especially women, who think to be too fat and are on a diet, but they aren't aware that long-lasting and strict diet may cause a lot of illnesses.
As far as the disadvantages of dieting are considered, there are many arguments against. The first of them is that diet makes us very unhappy. We harm ourselves by refusing to eat something we feel like having. What is more, TV and colour magazines promote only skinny models, so many women starve to achieve the slim figure, because it is thought that what the thinner is, the more attractive is.
If you decide to be on a diet, you cannot let yourself to eat everything you want. You are allowed to have only healthy food such as vegetables and fruit. Hamburgers, chips or pizza are strictly forbidden. You probably will harm yourself by avoiding sweets and chocolate. By dieting we don't fulfil all energy demands of our bodies, so we are becoming weaker and weaker. It can be very harmful for the body functions. Some women being on a diet starve, which seems to be completely unreasonable. When the diet is over, they usually put on weight much more thane they used to weigh. Dieting is very harmful especially for teenagers, whose bodies need a lot of energy supply to grow properly.
Finally, I think that we should consider that not only the thin girls are beautiful. There are a lot of girls who are said to be pretty, but they aren't slim. Bear in mind that the perfect figure isn't so important! What is important is inside.
Be careful if you decide to slim. Sometimes the diet brings more harms then profits.