This was a cute, quick read! I enjoyed it! However, I must say that it is incredibly wierd to read a book in which you name is used. One of the mean characters was called Caroline and I kept cringing on the inside, hahaha ^-^. 
 Additionally, if you liked Eleanor and Park, you'll most likely like this too :) 
 Holding up the Universe is about Jack and Libby - the popular guy and the new, overweight girl - who meet each other in a somewhat awkward way that changes each other's lives. 
 Libby is known for being America's Fattest Teen - she had to be rescued from her own house in her early teen years, which of course created a lot of hate towards her from her peers at school. Going back to the years later, she built herself a confidence that is often seen as violent and aggressive by other students. 
 Jack built himself a character - someone who is popular and confident in every sense of the word - because he has a mental condition called prosopagnosia. This is a condition where you can't recognize faces. Imagine seeing someone new, and when they turn away, you could not describe them anymore. Or not being able to describe your family, save for a few distinguishing features. 
 I think that this book handled face-blindness very well. I had no idea it could be so severe, and I can only imagine the situations it can get you in on a bad day. 
 Although I liked Jack as a character, I had a harder time with Libby. She was deffinetly unique and incredibly strong, but I had a hard time with her aggressiveness, sensitivity and stubbornness. I can understand it, but I feel like it was slightly overplayed. 
 Jennifer Niven is really quite a good author! She brings in many contemporary things such as music and books into the story, and she does one thing I absolutely love - short chapters! :D It's the best thing to read a book with short chapters - you just flip though them and don't see the pages go :) Also, she didn't fall into the insta-love trap. 
 I had a bit of a hard time with Jack and Libby together because it did feel like it was done very suddently, with a lack of chemistry at the beginning, but in the end (way end) I did think it was cute. I feel like the beginning of their relation could have been researched a bit more. 
 (Also, I'm sorry for this but I feel like I need to metion this little rant:) 
 A lot of people are criticizing this book because it is 'romanticizing mental ilness' and 'body-shamming by trying to be anti-body-shamming'. And yeah, I can get that - mental/physical illnesses/conditions are nothing to be tossed around lightly. Most of us might never know what it is to have one, and might never understand. My brother is very, very dyslexic. He's 14 and was diagnosed when he was 8, and I'm still trying to figure out what being dyslexic is like. I mean sure he has a hard time reading and can't memorize tha 2x3=6, but can solve a rubik's cube in less than a minute and is amazing with computers. 
 But putting down an author for writing about characters who are 'different' - in the sense of what we see in fashion magazines or in 'mentally healthy' people - is so, so disappointing. I understand it is a 'marker' of a person, or a label, and of course these types of topics are incredibly, excrutiatingly difficult to be accurate about when you don't personally experience them, but this book was good! You could tell how much research was done into understanding the circumstances the characters were in. I barely knew about prosopagnosia until now. Writing about this opens doors to people who don't know about these things. Instead of blaming an author for 'not knowing what he/she is writing about', try thanking them for trying to understand. 
 (rant over thanks for bearing with me ^^) 
 I'm giving this book a 4/5 feathers. Very cute and light read, but there were some things I had a little bit of a harder time with. 
 Have you read Holding up the Universe? What did you think about it? Let me know! :) 
 Have a great day!