On Nutrition

Ah, the humble potato. So misunderstood, so maligned, so scapegoated in this carb-phobic era. It’s an often repeated message that french fries and ketchup are two of the most commonly consumed “vegetables” in the collective American diet. And while, objectively, that’s far from ideal — although it’s the frying that truly knocks french fries out of contention for “health food” status — what about potatoes served up in other forms? Do they have a place in a nutritious diet? Does it matter what type of potato?

Potatoes, which originated in modern-day Peru and were domesticated approximately 8,000 years ago, are not some monolithic crop. Some 4,000 cultivated varieties are grown in 160 countries — so even the white, yellow, red, blue/purple and russet potatoes you’ll find in any well-stocked produce department or farmer’s market represent only a fraction of the possibilities.

Potatoes are rich in vitamin C — at various points in history, they may have prevented scurvy — and a better source of potassium than bananas. They also contain several B vitamins, some iron and other important nutrients. While they don’t contain much protein, we can easily absorb what protein they do have. If you eat the skin, you get a nice dose of fiber. Red and blue/purple potatoes contain anthocyanins, an antioxidant phytochemical also found in blueberries, strawberries, purple cabbage and other fruits and vegetables with red, blue and purple hues.

Before you point out that there are “healthier” foods that contain similar nutrients — and fewer carbohydrates — let’s look at the big picture.

First, there is not a thing wrong with including potatoes in a varied, balanced diet. Second, potatoes are an affordable staple crop in many countries, and have lower land and water needs than rice and wheat. According to the United Nations, potatoes play a big role in providing a sustainable food supply and lessening poverty and malnutrition in many parts of the world, so it’s a good idea to check our privilege when tempted to dismiss this nutritious, versatile food.

Also worth noting is that studies finding associations between higher potato intake and poor health outcomes don’t do a good job of teasing out the form in which those potatoes were eaten.


Another reason why potatoes get the side-eye from the health-conscious: they typically rank high on the glycemic index (GI), which means their carbohydrates are quickly broken down into sugar, which could quickly raise your blood-sugar levels. GI is highest in mashed potatoes, lowest in boiled or roasted potatoes, with baked potatoes somewhere in the middle. Similarly, waxy potatoes (such as red-skinned or fingerlings) have a lower GI than starch russet potatoes.

While the GI can be a useful tool for making carbohydrate choices that provide steadier energy, there are nuances to it that often get overlooked. For example, when you create balance in a meal or snack by pairing potatoes or other carb-rich foods with foods rich in protein and healthy fat — like roasted potatoes with salmon and broccoli — you digest the carbs more slowly and reduce any effects on blood sugar.

Now, I think the fear of carbs is overblown, but what’s interesting is that when potatoes are cooked then cooled, their starch becomes resistant to digestion — in other words, resistant starch. Resistant starch functions much like “fermentable fibers” in other plant foods, or good food for the beneficial bacteria that live in your gut (large intestine). When your gut microbes ferment resistant starch, they produce short-chain fatty acids (SCFAs) that appear to be important for human health in numerous ways. They may also increase feelings of satiety (pleasant fullness) after a meal.

If you’re trying to be gut-friendly by increasing fiber, research shows it’s often easier to increase resistant starch. Other good sources of resistant starch include pasta, pulses (beans and lentils), less-ripe bananas and rice and other grains.

Some tips for boosting resistant starch (and lowering GI) in potatoes:

  • Roast potato wedges, cool them and toss some into green salads. Or, cut them into smaller pieces and add them to scrambled eggs or a frittata — the starch remains “resistant” even if the cooled potatoes are reheated.
  • Boil and cool potatoes and toss them with vinaigrette, as with the delicious potato salad recipe below.

Herby Spring Potato Salad

Serves 6

This flavorful, aromatic potato salad can make the most of spring’s new potatoes, but it works equally well with fingerlings. Because this salad contains no eggs or mayonnaise, it’s also a more food-safe option for outdoor eating as we move into summer.


  • 1.5 pounds fingerling or new potatoes (preferably a mix of red, white and purple)
  • ¼ cup extra-virgin olive oil
  • 2 tablespoons fresh lemon juice
  • 1 tablespoon Dijon mustard
  • ½ teaspoon salt
  • ¼ teaspoon freshly ground pepper
  • 4 green onions
  • ¼ cup fresh dill, chopped
  • ¼ cup fresh flat-leaf parsley, chopped
  • Additional salt and pepper to taste

Place potatoes in a medium saucepan and cover with 1 inch of water. Bring to a boil, reduce to a simmer and cook for about 15 minutes, or until the tip of a sharp knife easily pierces a potato. Drain the potatoes in a colander and let them cool until they are almost room temperature.

Cut potatoes into halves or chunks (depending on the size of the potato) and add to a large bowl. Slice the green onions (the white and light-green parts) crosswise and add to the potatoes.

Whisk the vinaigrette ingredients until they start to emulsify and become creamy. Pour over the potatoes and gently toss to coat. Chop the herbs, sprinkle over the salad and gently toss again. Taste, adding additional salt and freshly ground pepper if needed. Serve.