Potatoes

Whether mashed, baked or roasted, people often consider potatoes as comfort food. It is an important food staple and the number one vegetable crop in the world. Potatoes are available year-round as they are harvested somewhere every month of the year. The potato belongs to the Solanaceae or nightshade family whose other members include tomatoes, eggplants, peppers, and tomatillos. They are the swollen portion of the underground stem which is called a tuber and is designed to provide food for the green leafy portion of the plant. If allowed to flower and fruit, the potato plant will bear an inedible fruit resembling a tomato.

This chart graphically details the %DV that a serving of Potatoes provides for each of the nutrients of which it is a good, very good, or excellent source according to our Food Rating System. Additional information about the amount of these nutrients provided by Potatoes can be found in the Food Rating System Chart. A link that takes you to the In-Depth Nutritional Profile for Potatoes, featuring information over 80 nutrients, can be found under the Food Rating System Chart.

• Health Benefits
• Description
• History
• How to Select and Store
• Tips for Preparing and Cooking
• How to Enjoy
• Individual Concerns
• Nutritional Profile
• References

Health Benefits

Potatoes are a very popular food source. Unfortunately, most people eat potatoes in the form of greasy French fries or potato chips, and even baked potatoes are typically loaded down with fats such as butter, sour cream, melted cheese and bacon bits. Such treatment can make even baked potatoes a potential contributor to a heart attack. But take away the extra fat and deep frying, and a baked potato is an exceptionally healthful low calorie, high fiber food that offers significant protection against cardiovascular disease and cancer.

Our food ranking system qualified potatoes as a very good source of vitamin B6 and a good source of potassium, copper, vitamin C, manganese, phosphorus, niacin, dietary fiber, and pantothenic acid.

Potatoes also contain a variety of phytonutrients that have antioxidant activity. Among these important health-promoting compounds are carotenoids, flavonoids, and caffeic acid, as well as unique tuber storage proteins, such as patatin, which exhibit activity against free radicals.

Blood-Pressure Lowering Potential

UK scientists at the Institute for Food Research have identified blood pressure-lowering compounds called kukoamines in potatoes. Previously only found in Lycium chinense, an exotic herbal plant whose bark is used to make an infusion in Chinese herbal medicine, kukoamines were found in potatoes using a new type of research called metabolomics.

Until now, when analyzing a plant’s composition, scientists had to know what they were seeking and could typically look for 30 or so known compounds. Now, metabolomic techniques enable researchers to find the unexpected by analyzing the 100s or even 1000s of small molecules produced by an organism.

“Potatoes have been cultivated for thousands of years, and we thought traditional crops were pretty well understood,” said IFR food scientist Dr Fred Mellon, “but this surprise finding shows that even the most familiar of foods might conceal a hoard of health-promoting chemicals.” Another good reason to center your diet around the World’s Healthiest Foods!

In addition to potatoes, researchers looked at tomatoes since they belong to the same plant family—Solanaceae—as Lycium chinense. Metabolomic assays also detected kukoamine compounds in tomatoes.

The IFR scientists found higher levels of kukoamines and related compounds than some of the other compounds in potatoes that have a long history of scientific investigation. However, because they were previously only noted in Lycium chinense, kukoamines have been little studied. Researchers are now determining their stability during cooking and dose response (how much of these compounds are needed to impact health).

Vitamin B6—Building Your Cells

If only for its high concentration of vitamin B6—1 medium potato contains over one-half of a milligram of this important nutrient—the potato earns high marks as a health-promoting food.

Vitamin B6 is involved in more than 100 enzymatic reactions. Enzymes are proteins that help chemical reactions take place, so vitamin B6 is active virtually everywhere in the body. Many of the building blocks of protein, amino acids, require B6 for their synthesis, as do the nucleic acids used in the creation of our DNA. Because amino and nucleic acids are such critical parts of new cell formation, vitamin B6 is essential for the formation of virtually all new cells in the body. Heme (the protein center of our red blood cells) and phospholipids (cell membrane components that enable messaging between cells) also depend on vitamin B6 for their creation.

Vitamin B6—Brain Cell and Nervous System Activity

Vitamin B6 plays numerous roles in our nervous system, many of which involve neurological (brain cell) activity. B6 is necessary for the creation of amines, a type of messaging molecule or neurotransmitter that the nervous system relies on to transmit messages from one nerve to the next. Some of the amine-derived neurotransmitters that require vitamin B6 for their production are serotonin, a lack of which is linked to depression; melatonin, the hormone needed for a good night’s sleep; epinephrine and norepinephrine, hormones that help us respond to stress; and GABA, which is needed for normal brain function.

Vitamin B6—Cardiovascular Protection

Vitamin B6 plays another critically important role in methylation, a chemical process in which methyl groups are transferred from one molecule to another. Many essential chemical events in the body are made possible by methylation, for example, genes can be switched on and turned off in this way. This is particularly important in cancer prevention since one of the genes that can be switched on and off is the tumor suppressor gene, p53. Another way that methylation helps prevent cancer is by attaching methyl groups to toxic substances to make them less toxic and encourage their elimination from the body.

Methylation is also important to cardiovascular health. Methylation changes a potentially dangerous molecule called homocysteine into other, benign substances. Since homocysteine can directly damage blood vessel walls greatly increasing the progression of atherosclerosis, high homocysteine levels are associated with a significantly increased risk for heart attack and stroke. Eating foods rich in vitamin B6 can help keep homocysteine levels low. In addition, diets high in vitamin B6-rich foods are associated with overall lower rates of heart disease, even when homocysteine levels are normal, most likely because of all the other beneficial activities of this energetic B vitamin.

A single baked potato will also provide you with over 3 grams of fiber, but remember the fiber in potatoes is mostly in their skin. If you want the cholesterol-lowering, colon cancer preventing, and bowel supportive effects of fiber, be sure to eat the potato’s flavorful skin as well as its creamy center.

Vitamin B6—Athletic Performance

Vitamin B6 is also necessary for the breakdown of glycogen, the form in which sugar is stored in our muscle cells and liver, so this vitamin is a key player in athletic performance and endurance.

Description

Whether it is mashed, baked or made into French fries, many people often think of the potato as a comfort food. This sentiment probably inspired the potato’s scientific name, Solanum tuberosum, since solanum is derived from a Latin word meaning “soothing”. The potato’s name also reflects that it belongs to the Solanaceae family whose other members include tomatoes, eggplants, peppers, and tomatillos.

There are about about 100 varieties of edible potatoes. They range in size, shape, color, starch content and flavor. They are often classified as either mature potatoes (the large potatoes that we are generally familiar with) and new potatoes (those that are harvested before maturity and are of a much smaller size). Some of the popular varieties of mature potatoes include the Russet Burbank, the White Rose and the Katahdin, while the Red LeSoda and Red Pontiac are two types of new potatoes. There are also delicate fingerling varieties available which, as their name suggests, are finger-shaped.

The skin of potatoes is generally brown, red or yellow, and may be smooth or rough, while the flesh is yellow or white. There are also other varieties available that feature purple-grey skin and a beautiful deep violet flesh.

As potatoes have a neutral starchy flavor, they serve as a good complement to many meals. Their texture varies slightly depending upon their preparation, but it can be generally described as rich and creamy.

History

Potatoes originated in the Andean mountain region of South America. Researchers estimate that potatoes have been cultivated by the Indians living in these areas for between 4,000 and 7,000 years. Unlike many other foods, potatoes were able to be grown at the high altitudes typical of this area and therefore became a staple food for these hardy people.

Potatoes were brought to Europe by Spanish explorers who “discovered” them in South America in the early 16th century. Since potatoes are good sources of vitamin C, they were subsequently used on Spanish ships to prevent scurvy. They were introduced into Europe via Spain, and while they were consumed by some people in Italy and Germany, they were not widely consumed throughout Europe, even though many governments actively promoted this nutritious foodstuff that was relatively inexpensive to produce. The reason for this is that since people knew that the potato is related to the nightshade family, many felt that it was poisonous like some other members of this family. In addition, many judged potatoes with suspicion since they were not mentioned in the Bible. In fact, potatoes initially had such a poor reputation in Europe that many people thought eating them would cause leprosy.

Some of the credit for the rise in potatoes’ popularity is given to two individuals who creatively engineered plans to create demand for the potato. In the 18th century, a French agronomist named Parmentier created a scheme whereby peasants could “steal” potatoes from the King’s “guarded” gardens. He also developed and popularized the mashed potato that became popular probably because he made this suspicious vegetable unrecognizable. Another person who was instrumental to the acceptance of potatoes was Count Rumford. A member of the British scientific group, the Royal Society, Rumford created a mush soup made of potatoes, barley, peas and vinegar, which the German peasants adopted as a satisfying and inexpensive dish.

It is thought that the potato was first brought to the United States in the early 18th century by Irish immigrants who settled in New England. People in this country were slow to adopt the “Irish potato” and large scale cultivation of potatoes did not occur in the U.S. until the 19th century.

There are not that many foods that can claim that a pivotal historical event centered around them. But the potato can. By the early 19th century, potatoes were being grown extensively throughout Northern Europe, and potatoes were almost solely relied upon as a foodstuff in Ireland owing to this vegetable’s inexpensive production and the poor economy of this country. Yet, in 1845 and 1846, a blight ruined most of the potato crop in Ireland and caused major devastation: this event is known as the Irish Potato Famine. Almost three-quarters of a million people died, and hundreds of thousands emigrated to other countries, including the United States, in search of sustenance.

Today, this once-infamous vegetable is one of the most popular throughout the world and the one that Americans consume more of pound for pound than any other. Currently, the main producers of potatoes include the Russian Federation, Poland, India, China and the United States.

How to Select and Store

While potatoes are often conveniently packaged in a plastic bag, it is usually better to buy them individually from a bulk display. Not only will this allow you to better inspect the potatoes for signs of decay or damage, but many times, the plastic bags are not perforated and cause a build up of moisture that can negatively affect the potatoes.

Potatoes should be firm, well shaped and relatively smooth, and should be free of decay that often manifests as wet or dry rot. In addition, they should not be sprouting or have green coloration since this indicates that they may contain the toxic alkaloid solanine that has been found to not only impart an undesirable taste, but can also cause a host of different health conditions such as circulatory and respiratory depression, headaches and diarrhea.

Sometimes stores will offer already cleaned potatoes. These should be avoided since when their protective coating is removed by washing, potatoes are more vulnerable to bacteria. In addition, already cleaned potatoes are also more expensive, and since you will have to wash them again before cooking, you will be paying an unnecessary additional cost.

Since new potatoes are harvested before they are fully mature, they are much more susceptible to damage. Be especially careful when purchasing these to buy ones that are free from discoloration and injury.

The ideal way to store potatoes is in a dark, dry place between 45F to 50F (between 7-10C) as higher temperatures, even room temperature, will cause the potatoes to sprout and dehydrate prematurely. While most people do not have root cellars that provide this type of environment, to maximize the potato’s quality and storage, you should aim to find a place as close as possible to these conditions. Storing them in a cool, dark closet or basement may be suitable alternatives. Potatoes should definitely not be exposed to sunlight as this can cause the development of the toxic alkaloid solanine to form.

Potatoes should not be stored in the refrigerator, as their starch content will turn to sugar giving them an undesirable taste. In addition, do not store potatoes near onions, as the gases that they each emit will cause the degradation of one another. Wherever you store them, they should be kept in a burlap or paper bag.

Mature potatoes stored properly can keep up to two months. Check on the potatoes frequently, removing any that have sprouted or shriveled as spoiled ones can quickly affect the quality of the others. New potatoes are much more perishable and will only keep for one week.

Cooked potatoes will keep fresh in the refrigerator for several days. Potatoes do not freeze well.

Tips for Preparing and Cooking

Tips for Preparing Potatoes

The potato skin is a concentrated source of dietary fiber, so to get the most nutritional value from this vegetable, don’t peel it and consume both the flesh and the skin. Just scrub the potato under cold running water right before cooking and then remove any deep eyes or bruises with a paring knife. If you must peel it, do so carefully with a vegetable peeler, only removing a thin layer of the skin and therefore retaining the nutrients that lie just below the skin.

Potatoes should be cleaned and cut right before cooking in order to avoid the discoloration that occurs with exposure to air. If you cannot cook them immediately after cutting, place them in a bowl of cold water to which you have added a little bit of lemon juice, as this will prevent their flesh from darkening and will also help to maintain their shape during cooking. As potatoes are also sensitive to certain metals that may cause them to discolor, avoid cooking them in iron or aluminum pots or using a carbon steel knife to cut them.

How to Enjoy

A Few Quick Serving Ideas

• Purée roasted garlic, cooked potatoes and olive oil together to make delicious garlic mashed potatoes. Season to taste.
• Potatoes are a featured ingredient in the classic dish, Salad Nicoise, that pairs new potatoes with chunks of tuna fish and steamed green beans dressed lightly with oil and vinegar.
• Toss steamed, diced potato with olive oil and fresh herbs of your choice.

For some of our favorite recipes, click Recipes.

Individual Concerns

Potatoes and Pesticide Residues

Virtually all municipal drinking water in the United States contains pesticide residues, and with the exception of organic foods, so do the majority of foods in the U.S. food supply. Even though pesticides are present in food at very small trace levels, their negative impact on health is well documented. The liver’s ability to process other toxins, the cells’ ability to produce energy, and the nerves’ ability to send messages can all be compromised by pesticide exposure. According to the Environmental Working Group’s 2014 report “Shopper’s Guide to Pesticides,” conventionally grown potatoes are among the top 12 fruits and vegetables on which pesticide residues have been most frequently found. Therefore, individuals wanting to avoid pesticide-associated health risks may want to avoid consumption of potatoes unless they are grown organically.

Potatoes Belong to the Nightshade Family

Potatoes are one of the vegetables in the nightshade (Solanaceae) family, which includes eggplant, tomatoes and bell peppers. Anecdotal case histories link improvement in arthritis symptoms with removal of these foods;however, no case-controlled scientific studies confirm these observations. For more on nightshades, please see our article “What are nightshades and in which foods are they found?”

Processed Potato Products and Acrylamides

Regularly cooked potatoes are not a concern when it comes to acrylamide, a potentially toxic and potentially cancer-causing substance. Yet, fried, processed foods made with potatoes—such as potato chips and french fries—are considered among the highest risk of foods when it comes to acrylamide exposure. This is yet another reason to avoid or minimize your intake of these foods. For more on acrylamides, see our detailed write-up on the subject.

Nutritional Profile

Potatoes are a very good source of vitamin B6 and a good source of potassium, copper, vitamin C, manganese, phosphorus, niacin, dietary fiber, and pantothenic acid.

For an in-depth nutritional profile click here: Potato.

In-Depth Nutritional Profile

In addition to the nutrients highlighted in our ratings chart, an in-depth nutritional profile for Potatoes is also available. This profile includes information on a full array of nutrients, including carbohydrates, sugar, soluble and insoluble fiber, sodium, vitamins, minerals, fatty acids, amino acids and more.

Introduction to Food Rating System Chart

In order to better help you identify foods that feature a high concentration of nutrients for the calories they contain, we created a Food Rating System. This system allows us to highlight the foods that are especially rich in particular nutrients. The following chart shows the nutrients for which this food is either an excellent, very good, or good source (below the chart you will find a table that explains these qualifications). If a nutrient is not listed in the chart, it does not necessarily mean that the food doesn’t contain it. It simply means that the nutrient is not provided in a sufficient amount or concentration to meet our rating criteria. (To view this food’s in-depth nutritional profile that includes values for dozens of nutrients – not just the ones rated as excellent, very good, or good – please use the link below the chart.) To read this chart accurately, you’ll need to glance up in the top left corner where you will find the name of the food and the serving size we used to calculate the food’s nutrient composition. This serving size will tell you how much of the food you need to eat to obtain the amount of nutrients found in the chart. Now, returning to the chart itself, you can look next to the nutrient name in order to find the nutrient amount it offers, the percent Daily Value (DV%) that this amount represents, the nutrient density that we calculated for this food and nutrient, and the rating we established in our rating system. For most of our nutrient ratings, we adopted the government standards for food labeling that are found in the U.S. Food and Drug Administration’s “Reference Values for Nutrition Labeling.” Read more background information and details of our rating system.

Potatoes, baked
1.00 medium
173.00 grams

Calories: 161
GI: high

NutrientAmountDRI/DV
(%)Nutrient
DensityWorld’s Healthiest
Foods Ratingvitamin B60.54 mg323.6very goodpotassium925.55 mg263.0goodcopper0.20 mg222.5goodvitamin C16.61 mg222.5goodmanganese0.38 mg192.1goodphosphorus121.10 mg171.9goodvitamin B32.44 mg151.7goodfiber3.81 g151.7goodpantothenic acid0.65 mg131.5goodWorld’s Healthiest
Foods RatingRuleexcellentDRI/DV>=75% OR
Density>=7.6 AND DRI/DV>=10%very goodDRI/DV>=50% OR
Density>=3.4 AND DRI/DV>=5%goodDRI/DV>=25% OR
Density>=1.5 AND DRI/DV>=2.5%

In-Depth Nutritional Profile for Potatoes

References

• Agricultural Research Service. “Phytochemical Profilers Investigate Potato Benefits,”. ,”Agricultural Research, September 2007. 2007.
• Breithaupt DE, Bamedi A. Carotenoids and carotenoid esters in potatoes (Solanum tuberosum L.): new insights into an ancient vegetable. J Agric Food Chem. 2002 Nov 20;50(24):7175-81. 2002.
• Ensminger AH, Ensminger, ME, Kondale JE, Robson JRK. Foods & Nutriton Encyclopedia. Pegus Press, Clovis, California. 1983.
• Ensminger AH, Esminger M. K. J. e. al. Food for Health: A Nutrition Encyclopedia. Clovis, California: Pegus Press; 1986. 1986. PMID:15210.
• Fortin, Francois, Editorial Director. The Visual Foods Encyclopedia. Macmillan, New York. 1996.
• Liu YW, Han CH, Lee MH et al. Patatin, the Tuber Storage Protein of Potato (Solanum tuberosum L.), Exhibits Antioxidant Activity in Vitro. J Agric Food Chem. 2003 Jul 16;51(15):4389-93. 2003.
• Parr A, Mellon F, Colquhoun I, Davies H. Dihydrocaffeoyl Polyamines (Kukoamine and Allies) in Potato (Solanum tuberosum) Tubers Detected during Metabolite Profiling. J Agric. Food Chem, 53 (13), 5461 -5466, 2005. 2005.
• Tudela JA, Cantos E, Espin JC et al. Induction of antioxidant flavonol biosynthesis in fresh-cut potatoes. Effect of domestic cooking. J Agric Food Chem. 2002 Oct 9;50(21):5925-31. 2002.
• Wood, Rebecca. The Whole Foods Encyclopedia. New York, NY: Prentice-Hall Press; 1988. 1988. PMID:15220.

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