Potatoes are the most commonly eaten vegetable in the United States with each person consuming an average of about 50 pounds a year, mostly in the form of French fries. Even though they are technically vegetables, potatoes are high in carbohydrates, and a new study suggests that eating four or more servings of potato a week can raise a person's risk of developing high blood pressure.

Researchers followed the diets of more than 187,000 men and women over 20 years using food questionnaires. Participants were drawn from three large studies, and none of them had been diagnosed with high blood pressure when the study began.

Potatoes can be part of a healthy diet. They are a good source of starch, which the body needs to form glucose for energy, and they provide healthy doses of vitamin C, potassium, magnesium and fiber (if the skin is eaten).

Those who ate four or more servings a week of boiled, baked, mashed or fried potatoes had a higher risk of developing high blood pressure than did those who ate less than one serving a month. It's no surprise that french fries were associated with a six percent higher risk for high blood pressure than the other forms of potatoes, but it was a surprise that potato chips did not seem to increase the risk of high blood pressure at all.

What’s so bad about potatoes? The problem may lie in the fact that people don’t tend to eat them plain or lightly seasoned. They are usually loaded — laden with butter, sour cream, cheese and bacon bits — or fried. French fries, unless homemade, are for the most part concoctions of salt and fat that are then fried.

Potatoes can be part of a healthy diet. They are a good source of starch, which the body needs to form glucose for energy, and they provide healthy doses of vitamin C, potassium, magnesium and fiber (if the skin is eaten). They contain no salt, fat or cholesterol, and a medium potato has only about 110 calories.

Those in the study who replaced one serving of potato — whether boiled, baked or mashed — with a non-starchy vegetable every day had a lower risk of developing high blood pressure. So it is possible to have your potato and eat it, too.

The study shows there is a positive association between eating potato and an increased risk for high blood pressure. It does not prove that potatoes are a cause of the disease, but they could be a contributing factor. The research report is published in the British Medical Journal.