Yam or sweet potato, what's the difference?

"You say tomato, I say tomahto,
You like potato, I like potahto,
Tomato, tomahto
Potato, potahto
Let’s call the whole thing off."

I figure it’s usually good to open with some music and those lyrics come to us courtesy of George Gershwin and his brother Ira. They were penned in 1937 for a musical starring Fred Astaire and Ginger Rogers called “Shall We Dance?” See the end of this write up for some more artists who saw fit to also cover this fine song.

Now, on to the matter at hand.

Here in the United States the term “yam” and “sweet potato” are used interchangeably. Most consumers of these edible tubers don’t make any distinction between the two and if a recipe calls for a yam and they see sweet potatoes at their local grocery store they figure that they’re one and the same. The opposite is also true, a yam can substitute for a sweet potato.

Would it surprise you to learn that other than being tubers, yams and sweet potatoes have nothing at all in common? Let’s take a look at some of the differences.

”I yam what I yam.”
Popeye

For starters, the word “yam” comes from the tribal languages of Africa and is spelt or pronounced as “njam, nyami, or djambi “ and literally means “to eat” in English. Found mostly in Africa, South America and in the islands of the Caribbean, yams are the product of a tropical vine. It's thought that the term came to North America as a result of the slave trade during the 1600 and 1700's. There are upwards of 600 different species with some them growing up to seven feet in length and weighing in at over 150 pounds. Many types of yams need to be cooked before they can be consumed in order to remove any toxins and while I wouldn’t try it, sweet potatoes can be eaten raw.

If you’re curious and want to see what a real nice set of yams looks like, just click on the link.

Worldwide there are literally thousands of varieties of sweet potatoes but here in America they are mostly grown in the southern states and California. I can’t begin to even fathom a seven foot tall 150 pound sweet potato at the grocery store. Stateside, the most popular types of sweet potatoes are “Goldrush”, “Georgia Red”, “Centennial”, “Puerto Rico”, “New Jersey”, and “Velvet”.

Another difference between a yam and a sweet potato is the family that they come from. Yams are closely related to grasses and lilies while sweet potatoes come from the morning glory family of plants.

As far as nutrition goes, yams generally contain more calories, carbohydrates and fiber while sweet potatoes are higher in Vitamin C and potassium. Both of them contain zero grams of fat.

So next time you’re at the grocery store and you’re thinking about picking up some either fresh or canned yams, just be aware, you’re probably buying some type of sweet potato.

As always, caveat emptor.

Source(s)

Oh yeah, I almost forgot. Other famous folks who also recorded “Let’s Call the Whole Thing Off” include the likes of:

karma debt says: I think it might be good to point out the family names for each (I know, I'm a plant geek and savant, blah blah blah). Yams are in the family Dioscoreaceae and sweet potatoes are in the family Convolvulaceae.