Yams vs. Sweet Potatoes: Benefits of Yam Nutrition (Plus Recipes and Side Effects)

Believe it or not, real yams aren’t very commonly found in the United States, even though many grocery stores label certain sweet potatoes as “yams.”

The orange tubers you find in supermarkets that are called yams are actually usually “soft” sweet potatoes.

According to the Farmers’ Almanac, when orange sweet potatoes were first introduced in the U.S., grocery stores called them yams to differentiate them from white sweet potatoes, which tended to be larger, drier and less appealing.

While these two root veggies are not the same thing and not even very closely related, both do provide many of the same nutrients — including antioxidants like beta-carotene (vitamin A), vitamin C, potassium and fiber.

What are yams?

Yams are tuberous root veggies that originated in Africa and Asia. Technically, yams are monocots, meaning they’re plants that have one embryonic seed leaf.

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Are yams potatoes? No.

Potatoes belong to the Solanaceae plant family, while yams belong to the Dioscoreaceae family (genus Dioscorea), and there are more than 600 varieties of yams!

Today, yams are grown in tropical climates, such as in places like South Africa, other African countries and the Caribbean. About 95% of yams today are grown in Africa.

It’s thought that yams got their name from the Fulani (a language spoken in Guinea, Western Africa) word nyami, which means “to eat.”

Types of yams grown around the world include:

• Indian yam (D. trifida)
• Winged or water yam (D. alata)
• Guinea yam (D. rotundata)
• Yellow Guinea yam (D. cayenensis)
• Lesser yam (D. esculenta)
• Chinese yam (D. polystachya), also known as cinnamon vine

Yam nutrition facts

Yams are a great source of complex carbs, fiber, vitamin A, vitamin C, potassium, manganese and other nutrients.

A one-cup serving of cooked yams (about 136 grams) contains approximately:

• Calories: 158
• Total Carbohydrates: 37.4 g
• Fiber: 5.3 g
• Sugar: 0.7 g
• Total Fat: 0.2 g
• Saturated Fat: 0.04 g
• Polyunsaturated Fat: 0.1 g
• Monounsaturated Fat: 0.01 g
• Protein: 2 g
• Sodium: 10.9 mg (<1% DV*)
• Manganese: 0.5 mg (22% DV)
• Copper: 0.2 mg (22% DV)
• Potassium: 911 mg (19% DV)
• Vitamin C: 16.5 mg (18% DV)
• Vitamin B6: 0.3 mg (18% DV)
• Thiamine: 0.1 mg (8% DV)
• Magnesium: 24.5 mg (6% DV)
• Phosphorus: 67 mg (5% DV)
• Folate: 21.8 mcg (5% DV)

*Daily Value: Percentages are based on a diet of 2,000 calories a day.

Yam nutrition also contains vitamins A, E and K; B vitamins niacin and pantothenic acid; and minerals calcium, iron, zinc and selenium.

Benefits

1. High in complex carbs and fiber

Tubers, including yams, are a good source of fiber, starch and energy. Compared to refined grains, most root vegetables are also lower in calories and lower on the glycemic index, which means they won’t spike your blood sugar as much.

The fiber in starchy veggies slows down the release of glucose (sugar), which is important for energy and insulin balance.

Additionally, plant foods that contain fiber have been shown to promote gut health and exhibit other beneficial activities, including having anti-carcinogenic, anticoagulant, immune-stimulating and antioxidant effects.

A high-fiber diet not only helps prevent inflammation and disease formation, but it also works wonders for helping with digestion and preventing irritable bowel syndrome or naturally relieving constipation.

2. Good source of vitamins A and C

Although they have less than sweet potatoes, yams provide you with antioxidants, including vitamins A and C.

These vitamins support a healthy immune system and fight free radical damage, while also combating inflammation. Diets rich in vitamins A and C help protect the skin, eyes, heart, brain and more from damage.

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3. High in copper, manganese and potassium

Yams are an excellent source of minerals, including copper, manganese and potassium, which have benefits for cardiovascular, metabolic and cognitive health.

Foods high in copper help form hemoglobin and collagen in the body, which supports circulation and healthy connective tissues, and are involved in energy metabolism, DNA synthesis and respiration.

Manganese foods can assist in nutrient absorption, production of digestive enzymes, bone development and immune-system defenses.

Potassium is a crucial electrolyte needed to maintain normal blood pressure levels, balance fluid levels in the body and facilitate muscle contractions.

4. Versatile and affordable

Another great thing about tubers is that they’re typically very inexpensive and available all year-round — plus they can be used in lots of ways. They’re a gluten-free source of carbs and useful for making baked fries, soups and starches for baking.

5. May aid blood glucose levels

Yams contain compounds like dioscoretine that may improve blood sugar control by enhancing insulin sensitivity, as shown in animal studies.

In addition, yams are high in resistant starch, and this type of starch has been linked to better blood glucose control and insulin sensitivity, among other benefits.

However, more trials on human subjects are needed to verify and understand these effects on people who have or at risk for diabetes.

6. May boost brain function

Yams are rich in diosgenin, a compound that may enhance neuron growth and improve cognitive function.

In a 12-week, placebo-controlled, randomized, double-blind, crossover study, healthy adults who consumed yam extract showed improved memory and learning abilities, indicating potential neuroprotective effects.

7. Could combat inflammation

The antioxidants in yams, such as polyphenols, may help reduce inflammation. Plus, research on the nutraceutical potential of Chinese yam has noted that this tuber has anti-inflammatory properties.

8. May help relieve menopause symptoms

Yams contain phytoestrogens that mimic estrogen in the body and may help alleviate menopausal symptoms.

A study published in the Journal of the American College of Nutrition found that postmenopausal women who replaced rice with yams in their diets in two out of three meals daily for 30 days experienced improved hormonal balance and reduced symptoms like hot flashes.

However, there have been mixed reviews.

A six-month study found yam supplementation had little effect on relieving menopause symptoms in 23 women who were dealing with unpleasant menopause symptoms. On the plus side, the study authors did note that the extract had little to no side effects.

More human research studies are needed to help confirm that yams can in fact help women with their menopause symptoms.

9. Might contain cancer-fighting properties

Yams have antioxidants that may help prevent oxidative stress linked to cancer development.

Yam-derived compounds have suppressed the growth of certain cancer cells in vitro and in animal studies, and in lab research, a lectin in Chinese yam led to breast cancer cell death.

More concrete evidence via human trials is needed to determine the cancer-fighting effects in humans.

10. Support digestion

The high fiber content in yams supports a healthy gut by promoting regular bowel movements and acting as a prebiotic.

In fact, researchers believe that yam consumption may be able to improve gut microbiota composition and digestive health.

11. May help balance cholesterol

Yams can help lower LDL (bad) cholesterol while boosting HDL (good) cholesterol. A 2005 study demonstrated that women consuming yams experienced a significant improvement in lipid profiles after 12 weeks.

12. Could be part of a weight maintenance diet

Fibrous foods are satiating and can actually help you lose weight because they fill you up. Starchy vegetables eaten with a balanced meal that includes protein and healthy fats have been shown to help control one’s appetite and delay hunger cues, which is important for weight management.

Due to their high fiber and resistant starch content, yams may aid in weight management by enhancing satiety and reducing calorie intake.

13. Possess antimicrobial effects

Yams contain bioactive compounds with antimicrobial properties that may protect against infections, as shown in lab studies. For instance, yam extracts have been shown to inhibit the growth of harmful bacteria and fungi in vitro.

Yams vs. sweet potatoes

Is a yam a sweet potato? No, these two root veggies are not related and are actually pretty different.

Both are tuberous root vegetables — however they are botanically different and come from different plant families.

Sweet potatoes are technically dicots, meaning plants that have two embryonic seed leaves. They belong to the Convolvulaceae plant family.

Compared to sweet potatoes, yams are usually bigger, starchier and drier, plus less sweet-tasting.

You can tell the difference by looking at the color of the skin and the flesh. This can be a bit confusing because there are lots of different types of sweet potatoes with a range of skin and flesh colors.

“Soft sweet potatoes” are considered those that have copper skin and deep orange flesh. Regular sweet potatoes are firm and have golden skin and lighter flesh.

You can also find purple, white and other colored sweet potatoes.

Sweet potatoes are much easier to find in grocery stores in the U.S., but real yams can be found at some international markets. If you’re buying tubers at regular markets, even if they are labeled as yams, chances are you’re actually buying sweet potatoes.

Which is healthier: sweet potato or yam?

Sweet potatoes are a great source of vitamin A, potassium, fiber and more. These are many of the same nutrients found in yams.

Overall, the two are comparable, but sweet potatoes are richer in vitamin A/beta-carotene.

How to use

Yams are described as having a mild, earthy flavor with a subtle sweetness. In order to make yams taste great, it’s important to cook them properly, which brings out their natural sweetness and makes them softer.

The most common ways to cook this starchy vegetable are to boil and mash them or fry, roast or bake them. They are used in similar ways to potatoes, either mashing them with herbs and butter, using them to make a sticky paste or dough that binds other ingredients, or frying them in fat/oil.

Bon Appetite magazine explains: “Yams are easily compared to the texture and flavor of white russet potatoes” due to their starchiness, rather than orange sweet potatoes or other softer varieties.

Try subbing in yams for potatoes in these healthy recipes or using a combination of both:

• Hasselback Potatoes
• Sweet Potato Hash
• Sweet Potato Biscuits
• Sweet Potato Rosemary Fries

Note: If you’re looking for the kind of root veggies that will have crisp skin and a fluffy orange flesh once cooked, you probably actually want to use sweet potatoes instead of real yams. Remember that deep orange sweet potatoes might be called yams in stores, but they are actually potatoes and usually wind up tasting a bit better and sweeter than real yams.

In terms of how long they last, you can keep yams for about four to six months if they’re stored in a cool, dim place. (Keep them out of the refrigerator and away from light and humidity.)

Risks and side effects

You never want to eat a raw yam, which can be a choking hazard and can also lead to digestive issues, since yams contain compounds that are potentially toxic when eaten raw. Always cook yams before eating them, which also makes their starch easier to break down.

If you’re following a low-glycemic diet or low-carb diet, limit the amount of root veggies you consume.

For the most health benefits, avoid deep-frying yams or eating with them lots of added sugar. Instead try boiling, roasting or baking them with a bit of avocado oil, herbs and spices.

Frequently asked questions

What does a yam look like?

Compared to regular white or sweet potatoes, yams tend to be bigger. They can sometimes grow up to three to four feet long and between 80 and 100 pounds.

They are usually cylindrically shaped, unlike potatoes, which tend to be tapered on the ends.

How do you know a yam is actually a yam?

One way to tell is the color of the root’s skin. Real yams have blackish or brown skin that is typically rough and scaly, sometimes described as being “bark-like.”

If you cut a yam open you’ll find flesh that is white, light purple, faint red or a mix of these colors, depending on the specific yam species.

Are edible yams the same as wild yam supplements?

“Wild yam” is the term used to describe a supplement that has estrogen-like effects. It’s derived from the root of the plant species called Dioscorea villosa, which grows on a vine native to North America.

Wild yam and other edible yams are related because they are in the same larger plant family.

Wild yam is usually found as a liquid extract, dried herb, powder, capsule, tablet or tea. It’s different from edible yams because it isn’t cooked and eaten, but instead it is taken as a natural remedy and supplement.

Conclusion

• What is a yam in the USA? Tubers that are labeled as “yams” in the U.S. are usually actually sweet potatoes. These two terms are mostly used interchangeably to describe soft, orange sweet potatoes, but technically these two roots are not related.
• Yams are tubers native to Asia and Africa that are starchy, large and dry. They have a brownish, scaly skin and flesh that can range from white to purple to red.
• Yam nutrition benefits include supplying you with vitamins A and C, potassium, manganese, B vitamins, fiber, and more.
• Look for yams in international markets, and use them in the same ways you would potatoes and other tubers.