Popeye's love of spinach is born out of one of history's easiest mathematical errors.

A mathematician and scientist has revealed that spinach's iron content was miscalculated by a German chemist when he misplaced a decimal point.

His mistake gave birth to Popeye's obsession with the vegetable, which the cartoon character eats in vast quantities to boost his strength.

Popeye's testimony that he is 'strong to the finish, 'cause I eats my spinach' is apparently born from a mistake 50 years before he became popular.


Erich von Wolf misplaced a decimal point when recording his research, making the iron content in spinach ten times more generous than in reality. This caused the popular misconception that spinach is exceptionally high in iron, which makes the body stronger...a myth that cartoon character Popeye (pictured) helped to spread

Samuel Arbesman talks about how scientific errors can lead to popular myths in his book, 'The Half-life of Facts: Why Everything We Know Has an Expiration Date'.

In 1870, German chemist Erich von Wolf was researching the amount of iron in spinach and other green vegetables.

When writing up his findings in a new notebook, he misplaced a decimal point, making the iron content in spinach ten times more generous than in reality.

While Mr von Wolf actually found out that there are just 3.5 milligrams of iron in a 100g serving of spinach, the accepted number became 35 milligrams thanks to his mistake.

This caused the popular misconception that spinach is exceptionally high in iron, which makes the body stronger.

If the value was true, eating a generous serving of spinach would be comparable to munching on a small piece of paper clip.

The story goes that cartoon creators aware of spinach's miraculous health properties had the idea that Popeye should eat spinach to increase his strength.

It is believed that the cartoon character is responsible for boosting consumption of spinach in the US by a third.


The incorrect calculation of spinach's iron content contributed to the creation of popular cartoon character Popeye, according to a book by mathematician and scientist Samuel Arbesman

While Mr von Wolf's error was spotted and corrected in 1937 when someone re-checked his maths, spinach is still popularly thought to be one of the most iron-rich vegetables, perhaps helped by the cartoon character.

In 1981, the British Medical Journal published an article to try and debunk the spinach myth.

Mr Arbesman uses the Popeye story to illustrate how humans have a tendency to ignore re-examining evidence and admitting when we are wrong.

He said that the reason such errors spread and lead to well-believed myths are because it is easier to spread a 'fact' that sounds correct than to delve deeper.


It is believed that Popeye is responsible for boosting consumption of spinach in the US by a third. While Erich von Wolf's error was spotted and corrected in 1937, spinach is still popularly thought to be one of the most iron-rich vegetables, perhaps helped by the cartoon character