Yam or sweet potato? A surprising difference
A rose is a rose … but a yam is not a sweet potato. It might even be possible you’ve never tasted a real yam. Those “candied yams” you serve on Thanksgiving probably are sweet potatoes.
Most people think those long, red-skinned sweet potatoes are yams, but they’re really just one of the many varieties of sweet potatoes. So where did all of the confusion come from?
A true yam is starchier and drier than a sweet potato; about 90 percent are imported from the Caribbean, Africa or Asia. Interesting fact: Nigeria exports 70 percent of the world’s yams. It is rough and scaly and very low in beta-carotene. The many varieties range drastically in size.
Most sweet potatoes are grown in the U.S. They can be either “firm” or “soft.” Firm sweet potatoes remain firm when cooked, while the soft type becomes moist. Depending on the variety, they can vary from white to orange and even purple flesh. The orange variety was introduced to the U.S. several decades ago. To distinguish it from the white variety we were used to, producers chose the English form of the African word “nyami” and labeled them “yams.”
Steve Mitchaud, produce manager at LifeSource, confirmed that grocers are allowed to use the term “yam” and “sweet potato” interchangeably, mainly to differentiate between orange and pale varieties. (You’ll find the darker ones labeled yams.) He also said he’s never seen a true yam in Salem — you’d have to shop in a major port city like Seattle or San Francisco because they’re imported from the southern hemisphere.
Sweet potatoes have more vitamin A, surprisingly, than yams; but yams have more potassium. They are both wonderful and nutrient-filled potato alternatives. The biggest difference in cooking is the need to cook yams longer to remove toxins. Unlike sweet potatoes, which can be eaten raw, yams always should be peeled and cooked because they contain many naturally occurring plant toxins including dioscorin.
Jessica Short is a registered dietitian for Salem health. Contact her atCHEC@salemhealth.org.
Easy Sweet Potato Slices
For Thanksgiving, try my Easy Sweet Potato Slices (recipe below) to replace candied yams. Serves 6. Start to Finish 35 minutes. Nutrition facts: Serving size 41 g; calories, 136 (86 from fat); total fat, 15%; no cholesterol; 9 mg sodium; 165 mg potassium; 11.4g carbohydrates; 1.6% dietary fiber; 7.4 g sugars; 3 g protein; 2% vitamin A; 11% vitamin C; 1% calcium; 8% iron.
1 sweet potato
1 tablespoon coconut oil, melted
1/2 cup walnuts or pecans
1/4 cup brown sugar
1/4 cup coconut flakes
Preheat oven to 350 degrees. Wash sweet potato really well. Slice it long ways into flat oval pieces. Place each piece onto a cookie sheet. Paint with melted coconut oil. Bake for 20 minutes or until the sweet potato is soft. In a sauté pan, toss together the nuts, brown sugar and coconut over medium heat until sugar melts and adheres to the nuts. Serve your sweet potato warm topped with the nuts.
Pop quiz: Yam, sweet potato or both?
1. I am a tuberous root with sweet moist flesh.
2. I am originally from Africa and am hardly sold in U.S. markets.
3. I am super sweet and can grow over 7 feet in length!
4. My skin can range from thin and pale to dark and thick.
5. I am toxic when eaten raw, but perfectly safe when cooked.
6. I am known for my high content of Vitamins A and C.
7. I have rough skin that is difficult to peel and can even be hairy at times, but it softens when baked.
8. My flesh can sometimes be purple!
9. I have an oblong body with tapered ends.
10. I have a very low glycemic index — a special health benefit to diabetics.
1. Both. Sweet potatoes and yams are considered tuberous roots and both are sweet and delicious.
2. Yam. Surprised? Yams grow in tropical climates, primarily in South America, Africa and the Caribbean.
3. Yam. They have higher sugar content than sweet potatoes and can grow to be enormous!
4. Sweet potato. Paler skinned sweet potatoes have white flesh, which is not as sweet and moist as the darker skinned, orange flesh sweet potatoes.
5. Yam. Unlike the sweet potato, yams must be cooked to eat safely. Preparation is a time-consuming process involving several minutes of pounding and boiling to remove toxins.
6. Sweet potato. Yams do not contain as much Vitamin A and C as sweet potatoes.
7. Yam. Sweet potato skin is thinner and smoother.
8. Both. Purple Okinawan sweet potato is often confused with the purple yam calledube.
9. Sweet potato. It can be short and fat or long and thin, but it will always taper at the ends.
10. Both. The sweet potato and yam are both loaded with potassium, magnesium and phosphorous.
— North Carolina Sweet Potato Commission website