Besides being good for you, potatoes were once a miracle crop. Imported to Europe from Central and South America around 1570, potatoes contributed needed calories and nutrients to the diet of the poor. Dependence on potatoes became so great that when the crop failed in Ireland in the 1840s, it led to widespread famine and massive emigration to the U.S. Today potatoes are almost universally grown--the world's most widely consumed and economically important vegetable.
The single biggest use: frozen French fries, especially at fast-food restaurants. Potatoes are indeed contributing to the obesity epidemic in the U.S., but that's primarily because they are fried or are covered in high-calorie ingredients like cheese, butter, cream, sour cream, or mayonnaise. Fast-food French fries are also a leading source of unhealthy trans fats - the stuff that clogs your arteries.
Potatoes have a bad reputation, in part, because they have a high glycemic index (GI) - a measure of how rapidly carbohydrates in foods cause blood sugar to rise. In theory, foods with a high GI are more likely to promote weight gain, but this remains unproven. Moreover, the GI looks at foods in isolation. For instance, if you eat a potato with some chicken, beef, or sour cream, its carbs are digested more slowly and blood sugar rises less.
How spuds stack up
A medium-size potato (6.5 ounces raw, about 5 ounces after baking), with its skin, has just 130 to 140 calories, virtually no fat, and 4 grams of fiber. It is one of the best sources of potassium, beating bananas handily. It's also a good source of vitamin C. But when loaded with toppings or dropped into a deep fryer, most of those health benefits begin to dwindle. Here are some nutritional comparisons:*
Baked potato, baked, 5 oz: 135 calories, 0 grams of fat
