Sharks: they prefer amino acids to blood | Photo: Greg Schechter/Creative Commons

What are the odds of being bitten by a shark? The question posed by a TMZ news reporter gets an odd answer from Laird Hamilton.

Mosquitoes kill 750,000 people every year. Shark attacks are responsible for about ten deaths worldwide. Humans are not the predator's favorite meal.

Nevertheless, unprovoked shark attacks occur on a regular basis nearly everywhere in the world. And according to big wave surfing legend Laird Hamilton, the main reason behind these attacks is women's menstruation.

"They say soda machines kill more people every year than people are bitten by sharks. Most shark attacks are not fatal. The biggest most common reason to be bitten is a woman with her period, which people don't even think about that," says Hamilton.

"Obviously, if a woman has her period then there's a certain amount of blood in the water. So, mistaken identity with the chances of you getting bit are greater than you getting struck by lightning."

"If you're a fisherman with bloody fish in the water or you're in a position where you're mistaken as a seal, these are all incidents to increase your odds; it's kind of like running around with a lightning rod and wondering why you get struck by lightening," concludes Hamilton.

The Hawaiian waterman is known for his controversial remarks. But could he be right when he says menstruation is the main reason why sharks attack humans?

It's only partially true, and it is definitely not the main reason. Sharks prefer amino acids to blood, and they usually attack at dawn and dusk in the areas where their natural preys live.

People with open cuts and menstruating women should take extra precautions, but human blood is not directly associated with shark attacks.

Discover why, when and how do sharks attack surfers, and learn how to defend yourself from the ocean's predator.