Sweet Potatoes and Garnet Yams Carb Information

Sweet Potato Carbs, Glycemic Index, Nutritional Information

Bowl of sweet potato salad
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Sweet potatoes are a yellow or orange-fleshed root vegetable, most popular at Thanksgiving. In the United States, yams (such as garnet yams) are a type of sweet potato. The root vegetable which is botanically a yam is quite different, but it is rare to find true yams in North America, as far as I know. Although sweet potatoes are very nutritious, they are also high in carbohydrates (although there seems to be a fair amount of individual variation on how sweet potatoes impact blood glucose).

Less starchy sources of many of the nutrients in sweet potatoes are carrots and pumpkin.

The easiest way to prepare sweet potatoes is to roast them whole in the oven (like you would a baked potato) until they are soft.  At 375 degrees F., this takes about 45 minutes, more if they are quite large.  The skin can be eaten along with the flesh of the sweet potato.

Carbohydrate and Fiber Counts for Sweet Potatoes

  • 1 medium sweet potato (5" long, 2" in diameter; about 4 oz - ¼ lb): 22 grams of effective (net) carbohydrate plus 4 grams of fiber and 112 calories
  • ½ cup cooked mashed sweet potato: 18 grams of effective (net) carbohydrate plus 3 grams of fiber and 90 calories
  • ½ cup canned unsweetened sweet potatoes, mashed: 28 grams of effective (net) carbohydrate plus 2 grams of fiber and 126 calories

Glycemic Index for Sweet Potatoes

The averages in studies of sweet potatoes ranged between 44 and 78, with an average of 61.

  Steaming chunks of sweet potato, rather than roasting, may lower the glycemic effect.  There is some research to indicate that in some people (and possibly with some varieties), sweet potato has properties that may lower the impact of its carbs on blood glucose.  This is an area where people vary, so checking your own blood glucose response seems prudent.

More Information about the Glycemic Index

Glycemic Load of Sweet Potatoes

  • 1 medium sweet potato (5" long, 2" in diameter; about 4 oz - ¼ lb): 10
  • ½ cup cooked mashed sweet potato:9
  • ½ cup canned unsweetened sweet potatoes, mashed: 12

More Information About the Glycemic Load

Health Benefits of Sweet Potatoes

Sweet Potatoes are an excellent source of vitamin A (the plant form), vitamin C, manganese, and all the carotenes, especially beta-carotene. It is also a very good source of vitamin B6 and potassium, and a good source of copper and fiber. They are also an excellent source of antioxidants which may help protect our cells from damage.  The phytonutrients in sweet potatoes also have been found to have anti -inflammatory properties.

Reduced-Carb Recipe with Sweet Potato

More Information About Sweet Potatoes at Calorie Count.

Compare the Carb Counts of Root Vegetables

More Carb Profiles:

    Leroux, MarcusFoster-Powell, Kaye, Holt, Susanna and Brand-Miller, Janette. "International table of glycemic index and glycemic load values: 2002." American Journal of Clinical Nutrition. Vol. 76, No. 1, 5-56, (2002).

    United States Department of Agriculture. "Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods - 2007. November 2007

    USDA National Nutrient Database for Standard Reference, Release 28.

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