Potatoes: Healthy or Unhealthy?
Potatoes are an incredibly versatile root vegetable consumed in a variety of dishes around the world.
While many people consider vegetables to be healthy, potatoes have managed to stir up some controversy.
Because of their starch content, many people believe they should limit their intake.
Also, potatoes are commonly associated with unhealthy fried and processed foods.
This article takes a deeper look at the potential health effects of potatoes.
Potatoes are a type of edible plant tuber eaten around the world.
Scientifically known as Solanum tuberosum, they belong to the nightshade family of plants ().
Originating in the South American Andes, potatoes are now cultivated in 160 countries worldwide, with 1,500–2,000 different varieties that range in color, size and nutrient content (, ).
Nevertheless, many varieties are similar in composition, consisting of a starchy flesh covered by a thin, nutrient-rich skin.
Potatoes can be boiled, steamed, fried, baked or roasted and used in a wide assortment of dishes.
Summary: Potatoes are an edible plant tuber cultivated around the world. There are many different varieties of potatoes that can be used in a range of dishes.
There are many types of potatoes that include an array of different nutrient sets.
One medium (6.1 ounces or 173 grams) Russet baked potato, including the flesh and skin, provides the following ():
- Calories: 168
- Fat: 0 grams
- Protein: 5 grams
- Carbs: 37 grams
- Fiber: 4 grams
- Sodium: 24 milligrams
- Vitamin C: 37% of the RDI
- Vitamin B6: 31% of the RDI
- Potassium: 27% of the RDI
- Manganese: 20% of the RDI
The nutrient profile of potatoes can vary depending on the type.
For example, red potatoes contain fewer calories, carbs and fiber than Russet potatoes, as well as slightly more vitamin K and niacin ().
The way you prepare your potatoes can also influence their nutrient content.
Given that many of their nutrients are concentrated in the outer skin, peeling the potato can remove a significant portion of the fiber and mineral content in each serving (, ).
Additionally, frying potatoes can increase their fat and calorie content, compared to other cooking methods like baking or boiling.
Furthermore, processed potato products are also less nutrient dense and contain more calories, fat and sodium than whole potatoes.
Summary: Potatoes contain a good amount of carbs and fiber, as well as vitamin C, vitamin B6, potassium and manganese. Their nutrient contents can vary depending on the type of potato and cooking method.
Antioxidants are substances that prevent the formation of harmful free radicals, which are reactive atoms that can accumulate in your body and contribute to chronic disease.
Studies show that antioxidants can prevent certain types of chronic disease, such as heart disease, diabetes and cancer (, , ).
Potatoes are a good source of antioxidants, including specific types, such as flavonoids, carotenoids and phenolic acids ().
One study compared the antioxidant activities of white and colored potatoes and found that colored potatoes were the most effective at neutralizing free radicals ().
Another test-tube study found that the antioxidants in potatoes may reduce the growth of certain types of cancer, including colon cancer and liver cancer ().
Keep in mind that most available research is limited to test-tube studies. More research is needed to determine how the antioxidants in potatoes may affect the development of chronic diseases in humans.
Summary: Potatoes contain antioxidants, which may reduce the risk of chronic disease. Although, further research is needed to study their potential effects in humans.
Resistant starch is a type of starch that is not digested in the small intestine.
Instead, it passes through to the large intestine, where it can feed the beneficial bacteria in your gut ().
Potatoes are a good source of resistant starch, and those that have been cooked and then chilled contain the highest amounts of it ().
Resistant starch has been associated with a number of health benefits, especially in terms of blood sugar control and insulin sensitivity.
In one study, 10 participants consumed 30 grams of resistant starch per day for a four-week period. They found that resistant starch increased insulin sensitivity by 33% ().
Another study had 10 participants supplement with 50 grams of raw potato starch. They experienced reduced blood sugar levels and increased satiety and fullness ().
While raw potatoes contain resistant starch as well, potatoes are typically cooked. This kills off bacteria and also degrades antinutrients, which can interfere with nutrient absorption ().
Furthermore, resistant starch may be associated with several other benefits, including reducing food intake, increasing nutrient absorption and improving digestive health (, , ).
Summary: Potatoes contain resistant starch, which may improve blood sugar control, digestive health, nutrient absorption and satiety.
Potatoes are recognized as one of the most filling foods available.
One study created a satiety index for common foods by giving 11–13 participants various foods and obtaining a satiety rating for each.
Boiled potatoes had the highest satiety rating and were considered seven times more satiating than croissants, which had the lowest score on the satiety index ().
Another study compared how the intake of rice, potatoes and pasta affected food intake and satiety in 11 participants. It found that potatoes were the most satiating and led to the greatest decrease in overall calorie intake ().
Potato skins also contain a good amount of fiber, which moves slowly through the body undigested, promoting fullness and decreasing hunger ().
Summary: Studies show that potatoes can increase satiety and decrease hunger, thanks to their fiber content and high density.
Some studies have found a positive association between eating certain types of potatoes and potato products and weight gain.
A 2009 study followed 42,696 participants over a five-year period. It found that eating potatoes was associated with an increase in waist circumference in women ().
Another study looked at the dietary patterns of over 120,000 participants.
It found that potatoes and processed potato chips were the two biggest contributors to weight gain, with each serving per day leading to an average weight gain of 1.3 pounds (0.58 kg) and 1.7 pounds (0.77 kg), respectively ().
However, it's important to take into account how often you eat them, how much you eat at once and how you prepare them.
In fact, other studies found no association between potato consumption and waist circumference or obesity (, ).
Certain processed potato products, such as French fries and chips, contain more calories and fat than potatoes that have been boiled, steamed or roasted. Excess calories, regardless of the food source, can lead to weight gain.
When eaten in moderation and as part of a balanced diet, it's unlikely that whole, unprocessed potatoes will lead to weight gain.
Summary: Some studies show that eating potatoes and processed potato products may lead to weight gain. However, when consumed in moderation, it's unlikely that potatoes themselves significantly contribute to weight gain.
Glycoalkaloids are a potentially toxic family of chemical compounds found in the nightshade family of plants.
Potatoes contain them, including two specific types called solanine and chaconine.
Green potatoes, in particular, are especially high in glycoalkaloids.
When potatoes are exposed to light, they produce a molecule called chlorophyll, causing them to turn green. Though the production of chlorophyll doesn't necessarily indicate spoilage, exposure to light can increase glycoalkaloid concentrations ().
When consumed in high amounts, these glycoalkaloids can be toxic and have adverse health effects.
One animal study showed that the glycoalkaloids found in potatoes could affect digestive health and may even aggravate inflammatory bowel disease ().
Other symptoms of glycoalkaloid toxicity include drowsiness, increased sensitivity, itchiness and digestive symptoms ().
However, when consumed in normal amounts, glycoalkaloids are unlikely to cause negative effects.
In fact, a 2005 study gave participants mashed potatoes containing a total glycoalkaloid concentration of 20 mg per 100 grams of potato, which is the recognized upper limit of safety, and found no adverse effects ().
About 60–70% of the total glycoalkaloid content of a potato is found in the peel.
Commercial peel-based products like wedges, slices and fried peels can contain 3.6–13.7 mg and 1.6–10.5 mg of solanine and chaconine per 100 grams, respectively (, ).
To minimize glycoalkaloid content, proper storage is key. Storing potatoes at lower temperatures and away from the light can prevent glycoalkaloid formation ().
Summary: Potatoes contain glycoalkaloids, which could be toxic if consumed in high amounts. Storing them at lower temperatures and away from the sunlight can keep glycoalkaloid content low.
When consumed in moderation, potatoes can be an excellent addition to your diet.
They contain good amounts of fiber and nutrients, plus they are very satiating and versatile.
However, the way you prepare them can make a big difference in terms of nutrition.
Many nutrients are contained in the peel of the potato, so consuming both the skin and flesh maximizes the amount of fiber, vitamins and minerals in each serving (, ).
Selecting a healthy cooking method is also important. Cooking them, rather than eating them raw, can kill off bacteria and break down antinutrients that interfere with the absorption of their nutrients ().
Baking, boiling and steaming potatoes are the best choices in terms of minimizing their fat and calorie contents, compared to frying.
Furthermore, opting for whole potatoes in place of processed potato products can decrease their fat, calorie and sodium contents.
What's more, choosing healthy toppings for your potatoes can improve their nutrient profile, making it a well-rounded and nutritious dish.
Summary: Keeping the peel on the potato, selecting nutritious toppings and choosing to boil, steam or bake your potatoes can make them healthier.
Potatoes are high in vitamins, minerals, antioxidants, fiber and resistant starch.
However, fried potatoes may also come with some potential negative effects, including weight gain, especially when consumed in large amounts.
Ultimately, portion size and cooking methods have a major influence on the health effects of potatoes.
When enjoyed in moderation and prepared in a healthy way, potatoes can be a nutritious addition to your diet.