Yams and sweet potatoes are not the same thing. In fact, you've probably bought a sweet potato, thinking it was yam!
There are many types of sweet potatoes ranging from white, yellow, red, purple, or brown on the outside with white, yellow, orange, and reddish flesh inside. There are also sweet potatoes that soften during cooking and those that stay firm.
When softer sweet potatoes first hit the market in the US, growers needed a way to differentiate between the two. The soft sweet potatoes resembled African yams, so growers just started calling them yams.
In reality, yams are much starchier and drier than sweet potatoes. They also aren't as sweet.
They're usually only found in international grocery stores so you would have to go out of your way to find them.
Confusingly, growers do still label some sweet potatoes yams but the USDA requires those labels to also mention that they're really just a type of sweet potato.
So next time you shop for "yams," looks closely, you might be in for a "sweet" (potato) surprise!
EDITOR'S NOTE: This video was originally published on October 12, 2017.