Spinach is a nutritional powerhouse. In addition to being high in iron, it contains high levels of vitamins B and C, as well as antioxidants like beta-carotene (which the body converts to vitamin A) and lutein. Spinach also is a good source of minerals, including magnesium and zinc [source: Seay].
If you're selecting canned or frozen spinach at the local supermarket, you don't need to employ a lot of strategy to find the right one. Simply check the expiration date, compare the price and make a decision. Fresh spinach, however, requires a bit more consideration. Fresh spinach should be consumed at the height of its color, so look for taut upright leaves with a deep, viridian hue -- the lush sort of green that brings to mind rainforests and leafy canopies. Then, turn a few of the leaves to make sure they are free of bruises, abrasions or yellowed areas.
Keep in mind that spinach is often grown in sandy soil, so unless you're purchasing the prewashed kind, you'll need to briefly soak the leaves in cold water, swish them around and then empty the bowl of debris. After a few rounds of this, you should have clean spinach at your fingertips [source: Beck]. Fresh spinach loses nutrients every day it is stored in the refrigerator so you may not want to buy more than you can consume quickly [source: Science Daily].
If you're using spinach as an ingredient when cooking, you'll need to pay attention to whether the recipe calls for fresh, canned or frozen. Fresh spinach is 92 percent water, which means you'll need a lot more of it to equal the same amount as a can of spinach [source: University of Kentucky]. This explains the differences in iron content in our list on the previous page. However you elect to ingest it there's a simple truth about spinach: It's good for you.
Author's Note: Is spinach really a good source of iron or not?
My first experience with spinach (that I remember, anyway) was in the cafeteria of my elementary school. All the foods we were served, from buttery rolls to mashed potatoes, were made in the school kitchen by a handful of fabulous cooks. It made such an impression that some of their now-adult students, including several of my classmates and myself, occasionally request a favorite school lunch recipe from the lunch ladies. I plan to surprise one of my older brothers with a batch of Whitewater Elementary School's frosted raisin bars the next time he's here for a visit, and there's one other dish I make quite often that's inspired by those early dining experiences. Cooked spinach. I know it's hard to imagine a bunch of elementary children tucking into a plate of cooked spinach, but I promise you it happened. Not only did these women put a lot of care into the food they whipped up for us, but they also encouraged us to sample a little of everything. Turns out they were right. Sometimes you just have to try it.
- Beck, Leslie. "Spinach." (Nov. 2, 2012) Leslie Beck. http://www.lesliebeck.com/ingredient_index.php?featured_food=85
- Borris, Hayley. "Commodity Profile: Spinach." February 2006. (Nov. 2, 2012) Agricultural Issues Center University of California. http://aic.ucdavis.edu/profiles/Spinach-2006.pdf
- Colorado State University. "2002: Year of the Spinach." Jan. 5, 2010. (Nov. 2, 2012) http://www.colostate.edu/Depts/CoopExt/4DMG/Whats/spinach1.htm
- Cronin, Brian. "Comic Book Legends Revealed." July 8, 2011. (Nov. 2, 2012) Comic Book Resources. http://goodcomics.comicbookresources.com/2011/07/08/comic-book-legends-revealed-322/
- Kruszelnicki, Karl. "Popeye's Spinach Story Rich in Irony." Dec. 6, 2011. (Nov. 2, 2012) ABC. http://www.abc.net.au/science/articles/2011/12/06/3384516.htm
- Leafy Greens Council. "Spinach." (Nov. 2, 2012) http://www.leafy-greens.org/greens/spinach.html
- Richter, Skip. "The Secret to Great Spinach." (Nov. 2, 2012) Texas Gardener. http://www.texasgardener.com/pastissues/sepoct03/spinach.html
- Seay, Mandy. "Five Superior Superfoods." (Nov. 2, 2012) Fit Day. http://www.fitday.com/fitness-articles/nutrition/5-superfood-staples.html#b
- Science Daily. "Storage Time and Temperature Effects Nutrients in Spinach." Feb. 28, 2005. (Nov. 2, 2012) http://www.sciencedaily.com/releases/2005/03/050323124809.htm
- Sutton, Mike. "The Spinach, Popeye, Iron, Decimal Error Myth is Finally Busted." Jan. 26, 2012. (Nov. 2, 2012) Best Thinking. http://www.bestthinking.com/articles/science/chemistry/biochemistry/the-spinach-popeye-iron-decimal-error-myth-is-finally-busted
- Tsang, R.D., Gloria. "Is Spinach a good source of Iron?" HealthCastle.com. (Nov. 8, 2012). http://www.healthcastle.com/iron-spinach.shtml
- University of Georgia. "Types of Leafy Greens." (Nov. 2, 2012) http://www.ugacfs.org/producesafety/Pages/Steps/LeafyGreenTypes.html#Spinach
- University of Kentucky. "Water Content of Fruits and Vegetables." (Nov. 2, 2012) https://docs.google.com/viewer?a=v&q=cache:LafG0sdngioJ:www.ca.uky.edu/enri/pubs/enri129.pdf+water+content+fresh+spinach&hl=en&gl=us&pid=bl&srcid=ADGEESinUfMz9CJ1XCwUxclnT5iYGh8-r-DPMeLcFP7_40I8tM8chQxyLR7_qawO8Cl_Juuw4YblBnevQAl94KPoeqx8d6ktze79qdez0rsj_MbTp88T84WNgVSB-wJFxv-Wq2tvbGP2&sig=AHIEtbSkuGX6-kuQjb7ZBUMuQj7NOgt4Gw
- USDA. "USDA National Nutrient Database for Standard Reference, Release 18." (Nov. 2, 2012) http://www.nal.usda.gov/fnic/foodcomp/Data/SR18/nutrlist/sr18w303.pdf
- USDA. "Vegetables Summary 2011." January 2012. (Nov. 2, 2012) http://usda01.library.cornell.edu/usda/current/VegeSumm/VegeSumm-01-26-2012.pdf