Are potatoes healthy?

(CNN)Yes, a plain baked potato is a healthy food, especially when it is consumed with its fiber-rich skin.

Advertisement

But because its nutrient profile and composition is different from other vegetables (it has more starch than leafy greens, for example), it shouldn't be the only vegetable in your diet.

Though potatoes may be thought of as a fattening food, a medium, unsalted plain baked potato with skin has only 160 calories and is naturally fat- and cholesterol-free. Each potato also packs about 4 grams of fiber and 4 grams of protein, which keeps us feeling full.

In fact, research suggests that potatoes are preferable to pasta in terms of their ability to reduce appetite after being consumed.

Potatoes offer many nutrients and minerals, but can become unhealthy if fried or loaded with butter, sour cream and cheese.

Potatoes also offer vitamin B6, vitamin C and iron, and are an excellent source of potassium. A medium potato provides about 20% of the recommended daily value for potassium, an important mineral that may help blunt sodium's effects on blood pressure.

One small study found that eating six to eight small antioxidant-rich purple potatoes twice daily does not cause weight gain and can help lower blood pressure and risk of heart disease and stroke among overweight individuals with hypertension.

Generally speaking, the type and amounts of nutrients among different potato varieties such as Russet, white and red potatoes may differ slightly, though not significantly. An exception is the sweet potato, which is a top food source of beta-carotene, an antioxidant that gets converted to vitamin A in our bodies and is important for healthy skin and eyes.

Potato pause

The problem with potatoes occurs when they are fried in a lot of oil, in the case of French fries or hash browns, which significantly boosts calories, fat and sodium.

Dressing potatoes with high-calorie ingredients can have similar effects. A plain potato can quickly morph into a fattening side dish when mashed with a lot of butter, topped with a heavy dollop of sour cream or mixed with mayonnaise to make potato salad.

While not as creamy, even a delicious dish like roasted potatoes tossed with olive oil, rosemary and Parmesan cheese will contribute more calories than its plain baked cousin -- though it can certainly be enjoyed as a small portion.

It is true that potatoes have been classified as having a high glycemic index (GI), which means they have a greater impact on blood sugar compared with foods with lower GIs, such as beans or non-starchy vegetables. However, the glycemic index doesn't tell the whole story about a food's nutritional value.

Additionally, one recent study found that there is substantial variability in individual responses to GI value determinations, and because of this, its usefulness in terms of guiding food choices is limited.

One study found that consumption of potatoes and French fries was associated with a modestly increased risk of type 2 diabetes in a large cohort of women.

However, the positive association between potato consumption and the risk of type 2 diabetes was seen primarily in obese and sedentary women, who are more likely to have underlying insulin resistance, which may intensify the adverse metabolic effects of higher glycemic carbohydrates, according to the study authors.

Another study found that women who ate four or more servings of baked, boiled or mashed potatoes per week had an increased risk of high blood pressure compared with those who consumed less than one serving per month. (French fries were associated with increased risk, too, among women and men.)

But equally surprising, the same study found that consuming an equivalent amount of potato chips was associated with lowered risk among men.

Bottom line? Potatoes offer important nutrients and can be a part of a healthy diet, as long as you are careful with preparation and portions.

Also, don't limit your veggies to white vegetables like potatoes. You'll miss out on nutrients in other colorful veggies that are important to health.