Sharks generally do not eat people intentionally, but they do sometimes mistake humans for other prey. Seals and sea lions are prominent staples in the shark's diet, and sometimes swimming humans resemble these creatures to a shark. Sharks have poor eyesight, so they detect food mainly with their mouths.
After realizing that a human isn't their preferred prey, sharks usually spit them out. Unfortunately, one bite from a shark can be lethal. Humans aren't an ideal food for sharks because humans are too bony and lack the nutrition of other prey. Seals and sea lions have a higher fat and energy content, which sharks need to sustain themselves.
Out of approximately 300 shark species, roughly twelve have been documented attacking humans. Sharks evolved to eat animals that were around millions of years before humans even existed, so they do not intentionally seek people out. Shark attacks usually get a significant amount of publicity, which is why many people fear them.
Experts recommend swimming away from sharks as quickly and calmly as possible. Because splashing attracts sharks, it is important to keep movements precise and calculated, Punching an attacking shark in the snout, head or eyes can be an effective way to get it to let go.