Are potatoes a dietary villain or a nutritional hero?
Debunking common myths and exploring the surprising health benefits of this versatile vegetable.
Culinary Medicine
by Lori A Smolin, PhD and
Potatoes are the most commonly consumed vegetable in the United States.[1] They provide many essential nutrients, are a versatile cooking staple, and have a mild flavor that works well in combination with a variety of foods. But we don’t typically think of them as healthy. They have been accused of contributing to weight gain, raising blood sugar, and increasing the risk of high blood pressure and heart disease.[2] Should we pass on the potatoes or embrace them as part of a healthy diet?
Significant and Sustainable Spuds
Some believe the potato may be the most important crop in human history. Potatoes originated in what is now Peru over 7000 years ago. In the 16th century, Spanish explorers brought them to Europe, where they helped end famine and feed the rapidly growing population. [3] Today, more than a billion people eat potatoes worldwide. [4] Potatoes are inexpensive, versatile and store well; when kept in a cool, dark, well-ventilated place they can remain fresh for months. We mash, bake, boil, and fry fresh potatoes and use them in pancakes, dumplings, soups and salads. We process them to make potato chips and a variety of frozen products such as Tater tots and French fries. Potatoes are environmentally friendly. They have low carbon and water footprints and requires less land for production than many fruits, grains, and other vegetables.[5] Their sustainability, nutritional properties and culinary versatility are reasons they were selected as the first vegetable to be grown in space, both in the real world and in Andy Weir’s 2011 novel The Martian.
Nutritional Benefits
When we think of potatoes, we typically think of their high carbohydrate content, but potatoes are more than just starch. They are high in fiber, free of cholesterol and fat, and moderate in calories with about 150 Calories in a medium potato. Although potatoes are mostly carbohydrate, they are also a source of high-quality protein; a medium potato has about 5 grams of protein – more than in half of a cup of milk or beans.[6] They provide vitamins and minerals, including vitamin C, niacin, vitamin B6, potassium, phosphorus, zinc, and iron. Potatoes also contain a variety of health-promoting phytochemicals.[7] Colored potatoes are generally higher than white potatoes in antioxidant phytochemicals; yellow-fleshed potatoes are high in carotenoids and purple and red ones are good sources of anthocyanins.
The fiber in potatoes is in both the skin and the flesh. The type of fiber in the flesh is called resistant starch, which is starch that is not digested by human enzymes in the small intestine. Resistant starch delays digestion, increasing satiety and delaying the rise in blood glucose after consumption. When resistant starch reaches the large intestine, it is broken down and consumed by bacteria, promoting a healthy microbiome. The amount of resistant starch in a potato is affected by the cooking method; boiling and then cooling potatoes increases the amount of resistant starch.
Potatoes and Chronic Disease
Potatoes have a bad reputation. We think of them as fattening and excess weight increases our risk for diabetes and heart disease. Some epidemiological studies have associated potato intake with an increased risk of obesity, type 2 diabetes, and heart disease. But a more thorough examination shows that when portions and preparation are considered, it is not the potatoes themselves that promote chronic disease. [8]
A review of the literature finds little evidence to suggest a relationship between the intake of potatoes and excess body weight.[2] Studies that compared satiety after consuming potatoes, pasta, rice, and bread, found potatoes to be the most filling; other studies found them even more satiating than many protein and fat-rich foods.[8] Choosing potatoes over rice or pasta may actually reduce the amount you eat and consequently the number of calories you consume in a meal.
French fries, however, are another story; A high intake of French fries may be associated with weight gain. [2] This is likely due to the calories that are added by frying. It is not the potato that is the culprit, but the calories added from the oil used to make French fries. French fry consumption has been associated with an increased risk of diabetes and hypertension. [8-11) There is little evidence to connect overall potato consumption to the risk of heart disease or diabetes. However, the added calories in fried potato and potato chips, and the butter, bacon and sour cream topping baked potatoes can contribute to weight gain.[2]
Potential Potato Woes
So, there is little evidence that potatoes are bad for your waistline, your blood sugar, or your heart but there are some potential potato hazards. Potatoes are a member of the nightshade family; nightshades contain solanine, a neurotoxin that could cause nausea and headaches in sufficiently high doses. Green coloration on the surface of a potato is an indicator of the solanine level; the green is actually chlorophyll but there is a corresponding increase in solanine. Solanine synthesis is promoted by light so levels can be reduced by storing potatoes in a cool dark place. Peeling potatoes removes most of the solanine because the chemical is found in the skin. For most people the risk of solanine toxicity from potatoes is low. Commercial varieties have been bred to have low levels; a 200-pound person would need to eat 20 pounds of potatoes in a day to experience toxic effects.[12]
Another potato hazard is acrylamide. Acrylamide forms from natural sugars and the amino acid asparagine in food during high-temperature cooking. High levels cause cancer in animals but the risk to humans is not completely understood. In general, cooking for longer periods at higher temperatures causes more acrylamide. Frying produces more acrylamide than boiling or baking. [13] An alternative to frying that limits acrylamide is to roast potatoes in small pieces.
The Bottom Line
The potato is a versatile, economical, nutritious vegetable that does not deserve its bad reputation. Potatoes have nourished populations for millennia and will continue to do so. How potatoes are prepared and what you add to it determines whether this ancient vegetable is a nutritional boost or dietary risk.
Great, Healthy Potato Recipes from FibonacciMD:
References
[1] USDA Potatoes and tomatoes are the most commonly consumed vegetables. USDA.gov. Published 2017. Accessed September 22, 2024. https://www.ers.usda.gov/data-products/chart-gallery/gallery/chart-detail/?chartId=58340#
[2] Borch D, Juul-Hindsgaul N, Veller M, Astrup A, Jaskolowski J, Raben A. Potatoes and risk of obesity, type 2 diabetes, and cardiovascular disease in apparently healthy adults: a systematic review of clinical intervention and observational studies. Am J Clin Nutr. 2016 Aug;104(2):489-98. doi:10.3945/ajcn.116.132332.
[3] Smithsonian Magazine How the Potato Changed the World. Smithsonian Magazine. Published November 2011. Accessed September 22, 2024. https://www.smithsonianmag.com/history/how-the-potato-changed-the-world-108470605
[4] International Potato Center. Potato Facts and Figures. International Potato Center. https://cipotato.org/potato/potato-facts-and-figures/
[5] Gustavsen G.W. Sustainability and Potato Consumption. Potato Res. 64, 571–586 (2021). https://doi.org/10.1007/s11540-021-09493-1
[6] Hussain M, Qayum A, Xiuxiu Z, Liu L, Hussain K, Yue P, Yue S, Y F Koko M, Hussain A, Li X. Potato protein: An emerging source of high quality and allergy free protein, and its possible future based products. Food Res Int. 2021 Oct;148:110583. doi: 10.1016/j.foodres.2021.110583.
[7] Raigond P, Jayanty SS, Parmar V, Dutt S, Changan SS, Luthra SK, Singh B. Health-Promoting compounds in Potatoes: Tuber exhibiting great potential for human health. Food Chem. 2023 Oct 30;424:136368. doi: 10.1016/j.foodchem.2023.136368
[8] Robertson TM, Alzaabi AZ, Robertson MD, Fielding BA. Starchy Carbohydrates in a Healthy Diet: The Role of the Humble Potato. Nutrients. 2018 Nov 14;10(11):1764. doi: 10.3390/nu10111764.
[9] Borgi L, Rimm EB, Willett WC, Forman JP. Potato intake and incidence of hypertension: results from three prospective US cohort studies. BMJ. 2016;353:i2351. Published 2016 May 17. doi:10.1136/bmj.i2351
[10] Schwingshackl L, Schwedhelm C, Hoffmann G, Boeing H. Potatoes and risk of chronic disease: a systematic review and dose-response meta-analysis. Eur J Nutr. 2019 Sep;58(6):2243-2251. doi: 10.1007/s00394-018-1774-2.
[11] Hu EA, Martínez-González MA, Salas-Salvadó J et al; PREDIMED Study and SUN Project Investigators. Potato Consumption Does Not Increase Blood Pressure or Incident Hypertension in 2 Cohorts of Spanish Adults. J Nutr. 2017 Dec;147(12):2272-2281. doi:10.3945/jn.117.252254
[12] University of Nebraska. Institute of Agriculture and Natural Resources. Cropwatch. Green Potatoes: The Problem. Published September 17, 2015. https://cropwatch.unl.edu/potato/greening
[13]U.S. Food and Drug Administration. Human Foods Program. Acrylamide and Diet, Food Storage, and Food Preparation. U.S. Food and Drug Administration. Published 2024. https://www.fda.gov/food/process-contaminants-food/acrylamide-and-diet-food-storage-and-food-preparation#:~:text=Comparing%20frying%2C%20roasting%2C%20and%20baking
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