The only reason I ate spinach when I was a kid was because I thought it might build my muscles and make me strong, like it did for Popeye. I asked my Mom, who told me that it was the high iron content in spinach that did the trick. It tasted like contaminated dirt, but I grinned and bore it, checking my biceps attentively after consumption.
But is spinach really such a great source of iron?
In 1870, a certain Dr. Emil von Wolf calculated that spinach has ten-times the iron of any other vegetable; so far, so good. Unfortunately, it wasn’t until 1937 that anybody checked his calculations, and it turns out that spinach has about the same iron content as many other vegetables; apparently, Dr. von Wolf had misplaced a decimal point during his calculations (update 2012-08-20 (see comments): this part of the story appears to be an interesting myth; it is vitamin A in spinach that was significant to Popeye’s creator; unfortunately, vitamin A is not known as a muscle-mass-increasing substance, so the thrust of my (hopefully) humorous post remains relevant).
Spinach does have a high nutritional value, rich in antioxidants, but Popeye’s choice of canned spinach is a low nutrient source compared to fresh, steamed, or quick-boiled. Spinach is an excellent source of vitamin A, vitamin K, vitamin C, vitamin E, manganese, folate, magnesium, betaine, vitamin B2, potassium, calcium, vitamin B6, folic acid, phosphorous, zinc, niacin, copper, selenium, and omega-3 fatty acids. And yes, it is a good source of iron, just not as magnificent as my boyhood self, with toothpick arms, had anticipated.
Popeye’s bulging biceps after consuming a can of spinach must have been due to the placebo effect.