Zarutskie - a Laguna Beach resident - was on vacation with her boyfriend and his family in the Bahamas and looking for the flawless Instagram shot.
However when she was encouraged to lie back by a local resident, Katarina was bitten by a shark with it pulling her under water for several seconds.
The outlet said her boyfriend's father was taking a photo of her as she floated near the sharks when one of them attacked.
After she was bitten, she held her arms up out of the water to keep her blood from attracting more sharks. Zarutskie was able to break free and swim to the shore.
Katarina Zarutskie was floating calmly in the ocean off the Bahamas' Staniel Cay when she suddenly felt her arm being yanked down.
Zarutskie has almost doubled her following on Instagram since her story came out; however, she has since made her account private, partly because she has "received a lot of rude and hateful comments from people that were saying ridiculous things", she told BBC.
Anyway, Katarina was swimming around with them when one of them obviously mistook her arm for a tasty morsel and bit down on it.
"I think if someone was screaming and flailing around it definitely could have changed the situation".
Zarutskie got stitches and antibiotics for the bite, and doctors believe she still has pieces of shark teeth in her arm.
She is upset at the way she has been stereotyped and accused of being social-media obsessed and careless.
When asked why she went ahead anyway, she replied, "It's just a once-in-a-lifetime experience".
The University of Miami nursing student was in Staniel Cay, an island in The Bahamas when she entered the marina to swim with a load of nurse sharks. "I guess you know you have to take it with a grain of salt and it comes with the territory". She went to the hospital to get treatment for her infected wounds.
An aspiring model and college student found out the hard way that swimming with sharks is not a good career move.