In the fitness world sweet potatoes are a staple, but are you eating a sweet potato or a yam? Is there a difference between them? The yam and sweet potato are not related and are 2 different types of vegetables.
Sweet Potato vs Yam
Yams are a monocot – meaning a plant having one embryonic seed leaf. It is part of the yam family closely related to lilies and grasses. Yams are native to Asia and Africa with over 600 varieties.
The yam has a rough scaly peel. The texture of the meat of the yam is dry and scratchy. The skin/peel varies in colors from light pink to dark brown with the color of the meat of the yam being white, yellow, and pink in older yams.
Yam is a good source of energy; ½ cup provides 118 calories. It is mainly composed of complex carbohydrates and soluble dietary fiber. Together, they raise blood sugar levels slower than simple sugars and are a low glycemic index healthy food.
Fiber helps reduce constipation. Fiber also decreases bad (LDL) cholesterol levels by the fiber binding with cholesterol in the intestines, which than lowers the risk of colon cancer by preventing toxic compounds in the food from adhering to the colon mucosa.
The yam is an excellent source of the B-complex group of vitamins. It provides adequate daily requirements of pyridoxine (vitamin B6), thiamin (vitamin B1), riboflavin, folic acid, pantothenic acid and niacin. These vitamins facilitate various metabolic functions in the body.
The Sweet Potato:
There are approximately 10 varieties of commercially grown Sweet Potatoes in the US, even though there are over 6500 varieties worldwide. Worldwide, Sweet Potato consumption is vast. All over the globe people use the potato, leaves, and roots.
The Sweet Potato is ranked among the top 5 most important food crops and is grown in over 100 countries. China produces and consumes about 90% of the world’s production of the sweet potato.
Sweet potatoes are a dicot – meaning a plant with two embryonic seed leaves. Sweet potatoes are part of the morning glory family. The origins of the sweet potato are in Peru and Ecuador. They were originally called “batatas.” The colors of sweet potatoes range from white, yellow, red, purple, and brown. The intensity of the sweet potato’s yellow or orange flesh color is directly correlated to its beta-carotene content.
Our bodies can typically produce vitamin A from the beta-carotene in orange-fleshed sweet potato. This is why this nutrient is often referred to as “Provitamin A.” Purple-fleshed sweet potatoes, on the other hand, are a fantastic source of anthocyanins (especially peonidins and cyanidins) and have outstanding antioxidant activity.
In one study, the antioxidant activity in the purple sweet potato was 3.2 times higher than that of a blueberry! An equally amazing fact about sweet potatoes is the antioxidant capacity of all their parts.
Recent research is showing that different genes are at work in the flesh versus skin of the sweet potato, producing different concentrations of anthocyanin antioxidants. Even the leaves of the sweet potato plant have been shown to provide important antioxidant benefits and can be included in soups and many other dishes.
Sweet potatoes can be grouped into two different categories depending upon the texture they have when cooked: some are firm, dry, and mealy, while others are soft and moist.
In both types, the taste is starchy and sweet with different varieties having different unique tastes. It has been thought that starchy root vegetables as a food group could not possibly be helpful in controlling blood sugar.
Many people surmise that food starches can be converted by our digestive tract into simple sugars. If foods are concentrated in starch, there can often be a risk of too much simple sugar released in our digestive tract, which results in the bloodstream to uptake more sugar. (The result in this situation would be a sudden increase of blood sugar levels.)
What’s compelling about the sweet potato is their ability to actually improve blood sugar regulation—even in persons with type 2 diabetes. As sweet potatoes contain an appreciable amount of dietary fiber (just over 3 grams per medium sweet potato) (and if the preparation is boiled or steamed) the Sweet Potato will have a very feasible glycemic index (GI) rating of approximately 50.
It may not be either of these factors that explain their unusual blood sugar regulating benefits.
Blood levels of adiponectin in persons with type 2 diabetes have been shown to significantly increase with the use of the extracts from Sweet Potatoes. Adiponectin is a protein hormone produced by our fat cells, and it serves as an important modifier of insulin metabolism.
Persons with poorly-regulated insulin metabolism and insulin insensitivity tend to have lower levels of adiponectin. Persons with healthier insulin metabolism tend to have higher levels of adiponectin.
The sweet potato is low in calories, high in fiber, fat free, cholesterol free, low in sodium, and among the highest in producing vitamin E, beta carotene and potassium. Choose sweet potatoes that are firm and do not have any cracks, bruises or soft spots.
Avoid those that are displayed in the refrigerated section of the produce department, since cold temperature negatively alters their taste.
Sweet potatoes should be stored in a cool, dark and well-ventilated place, where they will keep fresh for up to ten days. Ideally, they should be kept out of the refrigerator in a cool, dry, dark place.
Yet since most people don’t have root cellars, it is suggested to keep your sweet potatoes loose (not in a plastic bag, but if desired, a brown paper bag with multiple air holes punched in it will work) and store them in a cool, dark, and well-ventilated cupboard away from sources of excess heat (like the stove).
Nutritional Values for a Sweet Potato,
baked 1.00 medium baked /1 cup
Protein: 4.02 g
Carbohydrates: 41.42 g
Fat – total: 0.30 g
Dietary Fiber: 6.60 g
Total Sugars: 12.96 g
Calories from Fat: 2.70
Cholesterol: 0.00 mg
Vitamin B1: 0.21 mg
Vitamin B2: 0.21 mg
Vitamin B3: 2.97 mg
Vitamin B3 (Niacin Equivalents): 4.31 mg
Vitamin B6: 0.57 mg
Vitamin B12: 0.00 mcg
Biotin: 8.60 mcg
Choline: 26.20 mg
Folate: 12.00 mcg
Folate (DFE): 12.00 mcg
Folate (food): 12.00 mcg
Pantothenic Acid: 1.77 mg
Vitamin C: 39.20 mg
Vitamin A International Units (IU): 38436.00 IU
Vitamin A mcg Retinol Activity Equivalents (RAE): 1921.80 mcg (RAE)
Vitamin A mcg Retinol Equivalents (RE): 3843.60 mcg (RE)
Retinol mcg Retinol Equivalents (RE): 0.00 mcg (RE)
Carotenoid mcg Retinol Equivalents (RE): 3843.60 mcg (RE)
Alpha-Carotene: 86.00 mcg
Beta-Carotene: 23018.00 mcg
Beta-Carotene Equivalents: 23061.00 mcg
Vitamin E mg Alpha-Tocopherol Equivalents (ATE): 1.42 mg (ATE)
Vitamin E International Units (IU): 2.12 IU
Vitamin E mg: 1.42 mg
Vitamin K: 4.60 mcg
Minerals Boron: 215.78 mcg
Calcium: 76.00 mg
Chloride: 170.00 mg
Chromium — mcg —
Copper: 0.32 mg
Fluoride — mg —
Iodine: 6.00 mcg
Iron: 1.38 mg
Magnesium: 54.00 mg
Manganese: 0.99 mg
Molybdenum — mcg —
Phosphorus: 108.00 mg
otassium: 950.00 mg
Selenium: 0.40 mcg
Sodium: 72.00 mg
Zinc: 0.64 mg