Sweet potatoes (Ipomoea batatas) belong to the family Convolvulaceae, along with morning glories and over 1,000 other plants. It is the only species in the family that is widely cultivated for food. The large, starchy, sweet-tasting, tuberous roots of the sweet potato are a root vegetable. The young leaves and shoots are sometimes eaten as greens. Sweet potatoes are only distantly related to potatoes (Solanum tuberosum) and do not belong to the nightshade family.

Sweet potatoes were grown in Peru as far back as 8,000 BC. They had most likely been spread by local people to the Caribbean and South America by 2,500 BC. Sweet potatoes were also grown in the Cook Islands by 1,000 AD, possibly by Polynesians who had traveled to South America and back, and they spread across Polynesia to Hawaii and New Zealand from there.

Christopher Columbus probably found sweet potatoes on various islands of the West Indies on some of his earlier voyages, although they are definitely mentioned in the records of his fourth voyage.

In the islands off the coast of Yucatan and Honduras, sweet potatoes were called axi and batatas or betatas by the natives. In 1514, Peter Martyr named nine varieties that grew in Honduras. Sweet potatoes were taken to Spain about 1500 and several kinds were cultivated there by the middle of the 16th century, including red, purple, and white varieties. Belgians tried unsuccessfully to cultivate sweet potatoes in 1576. John Gerarde  claimed that in 1597 he grew the plant in England (probably without much success) and that it was known in India, Barbary, and other hot regions. Early Spanish explorers likely took sweet potatoes to the Philippines and East Indies, from which they were soon carried to India, China, and Malaya by Portuguese voyagers.

Sweet potatoes were cultivated in Virginia by 1648, and were likely taken into New England in 1764. They were grown by Native Americans in the South in the 18th century, and perhaps much earlier.

Sweet potatoes were likely introduced to Kyushu, the most southwesterly island of Japan, from China some time around 1700, by way of the Ryukyu Islands. In southern Kyushu today, sweet potatoes are commonly called kara-imo, meaning Chinese potatoes; but in most of the other parts of Japan it is called satsuma-imo (Japanese potato), although the relatively recent introduction of sweet potatoes into Japan is evidence that they did not originate in China or any other Asian country.

Sweet potatoes have become far more important in subtropical and tropical areas than has the white potato because the former thrive in a hot, moist climate, while the latter requires a cool climate. Sweet potatoes have therefore never become popular in Europe and are still rarely used even in the warmer Mediterranean areas. They are important in the warm Pacific islands, the East Indies, India, China, and are now the third most important food crop in Japan. In the past 25 years, plant breeders in Australia and in the warmer parts of the Soviet Union have become interested in the food-producing possibilities of sweet potatoes and have sought to develop their culture on a large scale.

Many Americans in the southern states prefer sweet potatoes to white potatoes; in the North the reverse is true. Generally speaking, the northern American consumers prefer the so-called “dry-fleshed” type of sweet potato, such as Big Stem Jersey and Little Stem Jersey, while the southerners prefer the “moist-fleshed” type, such as the Beauregard and Carolina Ruby varieties. Ironincally, the “dry-fleshed” sweet potatoes have more water in them than the “moist-fleshed” ones do. The soft, rich, “moist” varieties are erroneously called “yams” in the United States, although the yam an entirely different plant, belonging to the genus Dioscorea. True yams are rare in the United States.

The flesh of most sweet potato varieties is white or nearly so, although consumers in the United States prefer yellow or orange-fleshed varieties because of their valuable carotenoid content. Some kinds have purple flesh, but they are not grown in the U.S. Skin colors range from nearly white through shades of buff to brown or through pink to copper, even magenta and purple.

Sweet potatoes are now cultivated throughout tropical and warm temperate regions wherever there is sufficient water to support their growth.

Sweet potatoes can:

1. Help you control your appetite. Sweet potatoes are high in chromium, which enhances the actions of insulin, and is necessary for maintaining normal metabolism and storage of fats, proteins, and carbohydrates. They contain almost twice as much fiber as white potatoes, so their calories are burned more slowly and efficiently than a low-fiber food, which means they help you feel fuller, longer. One sweet potato has 4 grams or about 15% of your daily value of fiber. High-fiber, carbohydrate-rich foods have the ability to slow down the absorption of sugar in your blood and therefore, keep energy levels stable throughout the day, and keep your hunger satiated for longer. Sweet potatoes are also a great source of manganese, a mineral that is a pivotal component in the metabolism of carbohydrates, which helps support healthy blood sugar levels. This can help stabilize the appetite for hours as opposed to the temporary satisfaction that comes with most other carbohydrates. Manganese is also a cofactor in enzymes that play an important role in generating energy as well as efficiently using antioxidants.
2. Promote heart health. Sweet potatoes contain a large amount of vitamin B6. This vitamin is crucial in breaking down a substance called homocysteine, which contributes to hardening of the arteries and blood vessels. Vitamin B6 helps keep blood vessel walls flexible and healthy, which allows blood to flow freely. Sweet potatoes are also full of potassium, which can help lower your blood pressure by getting rid of extra sodium from your body and regulating fluid balance.
3. Fight cancer. Beta-carotene is the carotenoid and antioxidant that gives sweet potatoes their rich, reddish-orange color. Your body converts it to vitamin A, which helps get rid of cancer-promoting free radicals. People who consume at least four daily servings of beta-carotene rich fruits and vegetables have a lower risk of developing cancer or heart disease. Beta-carotenes also protect your skin from exposure to ultraviolet light, and support the health of your skin, eyes, and immune system. One medium sweet potato provides your body with all the vitamin A you need and then some. Sweet potatoes are also rich in vitamin C and vitamin E, which are also potent antioxidant vitamins that play an important role in disease prevention and longevity. They also contain oxalic acid, which is believed to be successful in fighting several kinds of tumor cells.
4. Prevent sugar cravings. Sweet potatoes are high in chromium, which enhances the actions of insulin. They have a relatively low glycemic index rating (50), which can also help prevent blood sugar spikes after you eat. Regulated blood sugar levels can help eliminate those sugar cravings you get when your levels dip. Just make sure you are steaming or boiling them, because roasting and frying them can destroy some of these properties.
5. Improve how you look and feel. The combination of beta-carotene, vitamin E, and vitamin C in sweet potatoes contributes to a healthy, glowing complexion and great hair. Sweet potatoes also help treat arthritis, anemia, and premenstrual symptoms. The vitamin B6 in sweet potatoes works as a mood enhancer and is used to treat people with mood disorders. SAMe, also known as SAM (s-adenosyl-methionine) is a substance synthesized in your body and required for cellular growth and repair. It is also involved in the biosynthesis of several hormones and neurotransmitters that affect mood, such as dopamine and serotonin. A complicated chemical cycle called the SAM cycle requires vitamin B6 in order to keep your body supplied with adequate amounts of SAM. Sweet potatoes also provide potassium, vitamin C, and fiber. Potassium is a natural way to lower blood pressure and help fuel your brain. Vitamin C helps in the production of endorphins. The fiber in complex carbohydrates is important for maintaining a healthy gut, which is crucial for the proper absorption of other nutrients. High-fiber, carbohydrate-rich foods have the ability to lessen mood swings. Diets low in fiber have been linked to depression and increased risk of suicide. When you’re feeling down, complex carbohydrates can help improve your mood in a healthy way.

Nutrients in 100 Grams Raw Sweet Potato

Nutrient	Amount	Daily Value
vitamin A	14187 IU	284%
chromium	27.69 µg	138%
manganese	0.258 mg	13%
fiber	3 g	12%
potassium	337 mg	10%
vitamin B6	0.209 mg	10%
pantothenic acid	0.8 mg	8%
copper	0.151 mg	8%
carbohydrates	20.12 g	7%
magnesium	25 mg	6%
phosphorus	47 mg	5%
thiamine	0.078 mg	5%
Calories	86	4%
vitamin C	2.4 mg	4%
riboflavin	0.061 mg	4%
calcium	30 mg	3%
folate	11 µg	3%
protein	1.6 g	3%
iron	0.61 mg	3%
niacin	0.557 mg	3%
sodium	55 mg	2%
vitamin K	1.8 µg	2%
zinc	0.30 mg	2%
vitamin E	0.26 mg	1%
selenium	0.6 µg	1%
biotin	1.45 µg	0.48%
fat	0.05 g	0.08%
cholesterol	0 mg	0%
carotene-ß	8509 µg	—
carotene-α	7 µg	—

When selecting sweet potatoes, it is important that they are firm to the touch and show no signs of decay. For even cooking, choose sweet potatoes that are uniform in shape.

Avoid storing sweet potatoes in the refrigerator, which will produce a hard center and unpleasant taste. Instead, store sweet potatoes in a cool, dry, well ventilated container, like a basket, for up to two weeks.

You can grate raw sweet potatoes into slaws and salads. They are delicious cooked whole. The skins of baked sweet potatoes become puffy and crisp, and the insides become sweet and soft. While baking is the most traditional way to cook sweet potatoes, there are many other ways to prepare them. When cooking whole sweet potatoes, pierce their skin several times with a fork and bake at 400 degrees for 40-50 minutes or until tender. Sauté sliced or diced sweet potatoes for about 10 minutes. Boil by adding 1-inch thick slices to a skillet with 2 inches of boiling water; cook for about 12 minutes. Steam 1-inch slices over simmering water. Microwave whole sweet potatoes for 5 to 8 minutes, rotating halfway through. Micro-bake whole sweet potatoes by microwaving for 4 minutes, then baking at 450 degrees for 5 to 10 minutes. Grill or broil 1-inch thick slices for 10 minutes or cut a sweet potato in half lengthwise and grill 20 to 25 minutes.

Try this decadent Praline Sweet Potato Casserole for Thanksgiving.

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This blog uses the latest nutritional data available from the USDA (United States Department of Agriculture), and the FDA (United States Food and Drug Administration), as well as nutritional data provided by food growers and manufacturers about their products. We believe the information on this website to be accurate. However, we are not responsible for typographical or other errors. Nutrition information for recipes is calculated by Living Cookbook based on the ingredients in each recipe based on statistical averages. Nutrition may vary based on methods of preparation, origin and freshness of ingredients, and other factors.

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