Potatoes have been a dietary mainstay in the United States, Europe and Central and South America for centuries. They were such an important source of calories and nutrients in Ireland that when the potato crop failed in the 1840s, there was a famine that led to a massive wave of immigration to the United States.

Why are potatoes good for you? Potatoes are higher in potassium than bananas and are a good source of the B vitamins, vitamin C, iron, magnesium and fiber. They are fat free, cholesterol free and very low in sodium. They are an excellent complex carbohydrate source and also provide protein. One medium potato counts as two vegetable servings in the food pyramid.

How does cooking affect nutrients in potatoes? The water soluble nutrients (B vitamins, vitamin C and potassium) are reduced because they leach into cooking water. Baking or boiling potatoes with the skins on helps to preserve these nutrients.

What does commercial processing do to potatoes? Dried, frozen and fast food potatoes lose water soluble nutrients and usually have added fat and sodium. Cooking fresh potatoes is your best choice, but if you use processed potatoes, check the food label to find the brand with the lowest fat and sodium.

Should you eat potato skins? Yes, because the skin is even higher in nutrients than the flesh. Do not eat skin that looks green. The green color is chlorophyll, which is not bad for you. But the formation of chlorophyll indicates that the potato has been exposed to sunlight which also causes formation of a toxic and bitter substance, called solanine. To prevent solanine formation, store potatoes in a cool, dark place.

Are potatoes fattening? A medium potato has about 140 calories and is one of the most filling foods you can eat. The problem comes from frying potatoes, which doubles the calories or loading them with high fat toppings, such as butter or margarine, sour cream, shredded cheese and bacon bits.

Is the effect of potatoes on blood sugar a concern? White potatoes do raise blood sugar more rapidly than many other carbohydrates. However, when combined with other foods in a meal, which is usually the way potatoes are eaten, the effect on blood sugar is greatly reduced. Reheating cooked potatoes or eating cooked potatoes cold, as in potato salad, also reduces the effect on blood sugar.

Visit the Auburn Farmers

Market Thursday, July 26, to taste an easy, delicious and nutritious potato salad, and visit www.cce.cornell.edu/cayuga for more nutrition information and easy recipes.

Christine Gutelius, MA, RD, CDN, is a nutrition resource educator at

Cornell Cooperative Extension of Cayuga County.

Provencal Potato Salad

Makes 6 servings

1 1/2 pounds small new potatoes, unpeeled

1 cup grape or cherry tomatoes, cut in halves

1/2 pound (about 2 cups) fresh green beans, cut in 1-inch pieces

1/4 cup chopped red onion

2 tablespoons oil

1 to 2 tablespoons vinegar

1 to 2 tablespoons Dijon-style mustard

1 teaspoon dried thyme or 1 tablespoon fresh thyme

1/4 teaspoon black pepper

3 tablespoons chopped fresh parsley

(or 1 tablespoon dried parsley)

Wash potatoes and cover with water in large pan. Heat water to boiling, reduce heat, cover and simmer potatoes 20 minutes or until cooked through. Add beans and simmer 1 1/2 minutes, covered. Drain and rinse with cold water. Cut potatoes into bite-size pieces. Place potatoes and beans in a large bowl. Add tomatoes and onion. Combine oil, vinegar, mustard, thyme and

pepper in small bowl. Stir with whisk. Pour

over potato mixture and toss gently to coat. Stir in parsley just before serving. Serve immediately or refrigerate and serve cold.