Spinach was Popeye's secret weapon – even giving the character the power to turn into a human rocket. But the reason illustrator E.C. Seegar chose spinach as Popeye's superpower-in-a-can may ...

At first there was no explanation for Popeye’s amazing strength. But within a few years Popeye’s reliance on spinach was entrenched in the strip, and the basis of some ongoing jokes.