Via Patrick Morgan of Discover Blogs' NCBI ROFL
So THAT’S why Popeye’s bulge was so large.
The effect of spinach on penile tumescence
“Spinach has long been praised for its many beneficial nutrients. Although not as iron-rich as originally reported (a fallacy that has become entrenched in popular culture), recent evidence suggests that the consumption of spinach may increase flow to blood-rich areas, including penile tissue. (more…)
Source: Discover Blogs
Sadly for the competing spinach capitals of the world (Alma, Arkansas, and Crystal City, Texas, claim that distinction) the publication date is April 1, 2011.
On the other hand I really want to thank Patrick Morgan for posting a link to the original sources (sources that are usually, as in this case, funded with federal grants) rather than gated/paywall sites where only the abstract is free.
