Yams, often confused with sweet potatoes, are a tuber native to Africa and Asia. They vary in size, and are generally cylindrical in shape. Yam flesh ranges in color from tan to pink or purple. Yams tend to be dry and starchy, providing a healthy energy source with important nutritional benefits.
Yams contain relatively little protein. Your body uses protein to build muscle, repair tissue and synthesize biological molecules such as enzymes and hormones. Protein also functions as a fuel source for your body if you don’t consume enough carbohydrates. Registered Dietitian Nancy Clark recommends a daily protein intake of 0.8 grams per pound of body weight. Although yams do not contribute significantly to your daily protein requirements, 1 cup offers over 2 grams of protein.
Almost all the carbohydrates in yams--nearly 40 grams in a 1-cup serving--are healthy complex carbs. These carbs fuel your body, allowing you to conserve your protein for uses other than energy production. Yams are also rich in fiber, a type of carbohydrate your body does not digest. While not a fuel source for your body, fiber helps maintain a healthy digestive tract and correlates with a decreased risk of obesity, heart disease and some forms of cancer, states the University of Illinois McKinley Health Center.
Yams are extremely low in fat, contributing less than 0.25 grams per 1-cup serving. While dietary fat is essential for maintaining healthy cell membranes, cushioning your organs and allowing your body to absorb fat-soluble vitamins, excess dietary fat may lead to cardiovascular disease. The low-fat content of yams may help you reduce your overall dietary fat consumption to a healthy level.
Yams are an excellent source of vitamins C and B6, with 1 cup providing approximately 20 percent of your daily requirement of each of these nutrients. Vitamin C assists in tissue repair and wound healing, and its antioxidant properties help offset the cell-damaging effects of free radicals in your body. Protein metabolism requires vitamin B6, and B6 also functions in the synthesis of red blood cells. Thiamin, another B vitamin, helps you convert carbohydrates to energy, and 1 cup of yams supplies 10 percent of your daily need for this vitamin.
Manganese, copper and potassium are abundant in yams, with a 1-cup serving providing roughly 20 percent of each of these essential minerals. The purpose of dietary manganese is not completely understood, says the Texas Heart Institute, although it is essential for good health and may help detoxify your body. Copper helps your body produce proteins such as hemoglobin, elastin and collagen. Potassium is involved in vital processes including energy production, muscles contraction and nerve impulses.
- University of Illinois McKinley Health Center: Macronutrients: The Importance of Carbohydrate, Protein, and Fat
- “Nancy Clark’s Sports Nutrition Guidebook”; Nancy Clark; 2008
- U.S. Department of Agriculture Nutrient Data Laboratory: Search
- MedlinePlus: Vitamins
- Texas Heart Institute: Trace Elements: What They Do and Where to Get Them