Other causes of stomach rumbles: 1  Incomplete digestion of food can lead to excess gas in the intestine. 2  Louder rumbles may occur when one is hungry. 3  Stomach rumbles can form further along the gastrointestinal system when air is swallowed while talking, eating, and drinking.
One cup of raw yams contains about 158 calories, whereas 1 cup of raw sweet potatoes contains about 114 calories. Therefore, yams contain about 44 more calories than sweet potatoes for an equal portion.
Russet, red and white potatoes share similar sugar and starch profiles. One medium potato has 2 grams of sugar and 23 to 30 grams of starch. Sweet potatoes have more sugar -- 7 grams -- but about the same amount of starch. When they're digested, both carbohydrates are broken down into the simple sugar glucose.