I think that there is much in way of strong thought in this section of the essay.  I believe that the first sentence needs to be broken up a bit.  A topic sentence to an essay like this should be rather precise and driven.  I feel that the first sentence contains several thoughts within it that might be better set if they are shown to be independent thoughts.  For example, try "The main concept demonstrated throughout this episode is how relationships and facing emotional issues can contribute to obesity."  This is a quick opening sentence that helps to drive the remaining of the paragraph.  Your next sentence could then be, "In addition to this, the show focuses on how society’s perception on people gaining weight is really shallow which causes them to not look at the real problem."  This helps to drive the paragraph with two strong sentences that can help provide a clear structure to it.  I would probably expand these ideas out a bit more in detail from what is seen in the episode, and I would refrain from the ending of the paragraph because the personalized opinions about the show in general take away from the analysis of the specific episode in question.