What’s the difference between yams and sweet potatoes?

There’s a bit of confusion in the food world around yams and sweet potatoes. What exactly is the difference — and what exactly are we cooking with? Let us lay some root vegetable knowledge on you.

Are Sweet Potatoes and Yams the Same?

Although sweet potatoes and yams are both root vegetables, they are not related to one another and differ in taste, texture and appearance.

Sweet potatoes originated in North America, first joining market shelves alongside the white potato as far back as the late 1600s. But back then, the sweet potato was also white or yellow in color. In the 1930s, a new orange version was cultivated, and to differentiate it from the white sweet potatoes, farmers borrowed the slang phrase “yams” that slaves from West Africa had used to describe them. Sweet potatoes reminded them of an African vegetable called nyami (watch Alton Brown’s segment on this here).

Today, the name “yams” has stuck as an interchangeable term for “sweet potatoes” in America. Generally speaking, if you’re reading a recipe (from Sweet Potato Pie to Candied Yams, pictured above) and everything in between), it means you can pick up sweet potatoes to make it — even if they’re labeled “yams” at the grocery store.

The Difference Between Yams and Sweet Potatoes

There are indeed many differences between nyami – African yams – and sweet potatoes. African yams might also be refered to as Nigerian yams, true yams, Ghana yams, puna yams or white yams.

African yams have thick, brown, bark-like skin and yellow coloring. They can easily weigh up to 55 pounds. American sweet potatoes have thin, papery skin and that widely-recognized orange flesh (but can also come in a variety of colors, like yellow or purple).

African yams are much starchier than sweet potatoes and are closer to the texture of yucca. They taste earthy, a bit like a potato. Sweet potatoes are known for their smooth potato-like texture and sweet flavor.

Both can be mashed, roasted or boiled or fried.

African yams are not available at most supermarkets, but can be found at African or Caribbean markets.

How to Buy and Store Sweet Potatoes

Yes, you can buy sweet potatoes all year long, but their flavor peaks in the fall and winter. Select sweet potatoes that are heavy for their size, and make sure to avoid ones that have sprouts or soft spots.

Store them in a cool, dry, ventilated space and use them within 15 days of buying them. Make sure to handle them gently because they bruise more easily than regular potatoes.

A few common varieties are white, Jewel, Japanese, Beauregard and Boniato. You can use them interchangeably, but if you taste two varieties side-by-side, you might notice that they have different flavors and levels of sweetness.