According to the National Oceanic and Atmospheric Administration (NOAA), the great white shark has an extensive diet that may include leatherback sea turtles. Turtles are not the normal diet of a shark, as they prefer to eat seals, fish and other sharks.
In spite of being perceived as dangerous to humans, a shark will usually only attack a human when it is confused or curious. A shark that sees a person splashing in the water may come in close to investigate, which can lead to an accidental attack. Sharks have more to fear from humans because they are often hunted for their meat, organs and skin.