I was recently asked by a user of our free vertical jump program if we knew anything about spinach being a steroid, so before I answered I researched the World Wide Web and found some interesting information. 

Yes it's true, Popeye got his muscles from eating spinach. According to the study out of Rutgers University, Brown Medical School and the University of Illinois, spinach has a steroidal effect, however you will need to eat 2.2 pounds of spinach per day to gain this effect. The test was done on lab rats who must have needed muscles for some reason. 

Before you start eating insane amounts of spinach you should now that there are some side effects of eating a ton of spinach. 
  • Too much spinach can cause bladder and kidney stones 
  • The acid in spinach can inhibit the absorption of calcium 
  • Spinach contains lots of fiber, this would lead to added trips to the bathroom at the most inconvenient times
If you want to add spinach to your diet you should start now, but I would suggest not eating 2.2 pounds per day as that can really hurt your wallet and your toilet. 

Link to the study