Turnip greens

You'll want to include turnip greens as one of the cruciferous vegetables you eat on a regular basis if you want to receive the fantastic health benefits provided by the cruciferous vegetable family. At a minimum, include cruciferous vegetables as part of your diet 2-3 times per week, and make the serving size at least 1-1/2 cups. Even better from a health standpoint, enjoy turnip greens and other vegetables from the cruciferous vegetable group 4-5 times per week, and increase your serving size to 2 cups. We recommend Healthy Steaming turnip greens for maximum nutrition and flavor. Cut greens into 1/2-inch slices and let sit for at least 5 minutes to enhance it health-promoting benefits and steam for 5 minutes. Toss with our Mediterranean Dressing (see Healthiest Way to Cook Turnip Greens in the How to Enjoy section below).

This chart graphically details the %DV that a serving of Turnip greens 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 Turnip greens can be found in the Food Rating System Chart. A link that takes you to the In-Depth Nutritional Profile for Turnip greens, 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

Unlike some of their fellow cruciferous vegetables, turnip greens have not been the direct focus of most health-oriented research studies. However, turnip greens have sometimes been included in a longer list of cruciferous vegetables that have been lumped together and studied to determine potential types of health benefits. Based upon several dozen studies involving cruciferous vegetables as a group (and including turnip greens on the list of vegetables studied), cancer prevention appears to be a standout area for turnip greens when summarizing health benefits.

This connection between turnip greens and cancer prevention should not be surprising since turnip greens provide special nutrient support for three body systems that are closely connected with cancer development as well as cancer prevention. These three systems are (1) the body's detox system, (2) its antioxidant system, and (3) its inflammatory/anti-inflammatory system. Chronic imbalances in any of these three systems can increase risk of cancer, and when imbalances in all three systems occur simultaneously, the risk of cancer increases significantly. Among all types of cancer, prevention of the following cancer types is most closely associated with intake of turnip greens: bladder cancer, breast cancer, colon cancer, lung cancer, prostate cancer, and ovarian cancer.

Detox Support

The detox support provided by turnip greens includes antioxidant nutrients to boost Phase 1 detoxification activities and sulfur-containing nutrients to boost Phase 2 activities. Turnip greens also contain phytonutrients called glucosinolates that can help activate detoxification enzymes and regulate their activity. Two key glucosinolates that have been clearly identified in turnip greens in significant amounts are gluconasturtiian and glucotropaeolin.

If we fail to give our body's detox system adequate nutritional support, yet continue to expose ourselves to unwanted toxins through our lifestyle and our dietary choices, we can place our bodies at increased risk of toxin-related damage that can eventually increase our cells' risk of becoming cancerous. That's one of the reasons it's so important to bring turnip greens and other cruciferous vegetables into our diet on a regular basis.

Antioxidant Benefits

As an excellent source of vitamin C, vitamin E, beta-carotene, and manganese, turnip greens provide highest level support for four conventional antioxidant nutrients. But the antioxidant support provided by turnip greens extends far beyond these conventional nutrients and into the realm of phytonutrients. Hydroxycinnamic acid, quercetin, myricetin, isorhamnetin, and kaempferol are among the key antioxidant phytonutrients provided by turnip greens. This broad spectrum antioxidant support helps lower the risk of oxidative stress in our cells. Chronic oxidative stress—meaning chronic presence over overly reactive oxygen-containing molecules and cumulative damage to our cells by these molecules—is a risk factor for development of most cancer types. By providing us with a diverse array of antioxidant nutrients, turnip greens help lower our cancer risk by helping us avoid chronic and unwanted oxidative stress.

Anti-inflammatory Benefits

As an excellent source of vitamin K and a good source of omega-3 fatty acids (in the form of alpha-linolenic acid, or ALA), turnip greens provide us with two hallmark anti-inflammatory nutrients. Vitamin K acts as a direct regulator of our inflammatory response, and ALA is the building block for several of the body's most widely-used families of anti-inflammatory messaging molecules. While glucobrassicin (a glucosinolate found in many cruciferous vegetables, and the precursor for the anti-inflammatory molecule indole-3-carbinol) does not appear to be present in turnip greens in significant amounts, other glucosinolates present in turnip greens may provide important anti-inflammatory benefits and are the subject of current research.

Like chronic oxidative stress and chronic weakened detox ability, chronic unwanted inflammation can significantly increase our risk of cancers and other chronic diseases (especially cardiovascular diseases).

Cardiovascular Support

Researchers have looked at a variety of cardiovascular problems—including heart attack, ischemic heart disease, and atherosclerosis—and found preliminary evidence of an ability on the part of cruciferous vegetables to lower our risk of these health problems. Yet regardless of the specific cardiovascular problem, it is one particular type of cardiovascular benefit that has most interested researchers, and that benefit is the anti-inflammatory nature of turnip greens and their fellow cruciferous vegetables. Scientists have not always viewed cardiovascular problems as having a central inflammatory component, but the role of unwanted inflammation in creating problems for our blood vessels and circulation has become increasingly fundamental to an understanding of cardiovascular diseases. While glucoraphanin (a glucosinolate found in many cruciferous vegetables, and the precursor for sulforaphane, an isothiocyanate with important anti-inflammatory properties) does not appear to be present in turnip greens in significant amounts, other glucosinolates present in turnip greens may provide important anti-inflammatory benefits and are the subject of current research.

A second area you can count on turnip greens for cardiovascular support involves their cholesterol-lowering ability. Our liver uses cholesterol as a basic building block to product bile acids. Bile acids are specialized molecules that aid in the digestion and absorption of fat through a process called emulsification. These molecules are typically stored in fluid form in our gall bladder, and when we eat a fat-containing meal, they get released into the intestine where they help ready the fat for interaction with enzymes and eventual absorption up into the body. When we eat turnip greens, fiber-related nutrients in this cruciferous vegetable bind together with some of the bile acids in the intestine in such a way that they simply stay inside the intestine and pass out of our body in a bowel movement, rather than getting absorbed along with the fat they have emulsified. When this happens, our liver needs to replace the lost bile acids by drawing upon our existing supply of cholesterol, and as a result, our cholesterol level drops down. Turnip greens provide us with this cholesterol-lowering benefit whether they are raw or cooked. However, a recent study has shown that the cholesterol-lowering ability of raw turnip greens improves significantly when they are steamed. In fact, when the cholesterol-lowering ability of steamed turnip greens was compared with the cholesterol-lowering ability of the prescription drug cholestyramine (a medication that is taken for the purpose of lowering cholesterol), mustard greens bound 34% as many bile acids (based on a standard of comparison involving total dietary fiber).

It's impossible to talk about the cardiovascular benefits of turnip greens without also mentioning their exceptional folate content. Although this cruciferous vegetable scores a rating of "excellent" in our food rating system, we would like to point out just how "excellent" excellent is when you're talking about turnip greens. These greens provide 575 micrograms of folate in every hundred calories. That's an amount that is unsurpassed by the most commonly-eaten cruciferous vegetables! Folate is a critical B-vitamin for support of cardiovascular health, including its key role in prevention of homocysteine build-up (called hyperhomocysteinemia).

Digestive Support

The fiber content of turnip greens—over 5 grams in every cup—makes this cruciferous vegetable a natural choice for digestive system support. And although not yet confirmed in large-scale human research studies, we eventually expect to see some special digestive benefits coming from turnip greens in the area of glucosinolates, isothiocyanates, and stomach bacteria. While glucoraphanin (a glucosinolate found in many cruciferous vegetables, and the precursor for sulforaphane, an isothiocyanate with important properties involving regulation of a stomach bacteria called Helicobacter pylori) does not appear to be present in turnip greens in significant amounts, other glucosinolates present in turnip greens may provide similar health benefits with respect to prevention of Helicobacter pylori overgrowth in our stomach or too much clinging by this bacterium to our stomach wall.

Description

All cruciferous vegetables provide integrated nourishment across a wide variety of nutritional categories and provide broad support across a wide variety of body systems as well. For more on cruciferous vegetables see:

• Eating Healthy with Cruciferous Vegetables
• Feeling Great with Cruciferous Vegetables

Turnip greens are the leaves of the turnip plant, better known for its tasty root. Turnip, which scientifically known as Brassica rapa, belongs to the Cruciferae family, a cousin to other health-protective giants including kale, collards, cabbage, and broccoli.

Turnip leaves are smaller and more tender than their cousin, collards. Their slightly bitter flavor is delicious. Turnip greens are an important vegetable in traditional Southern American cooking.

History

Turnips are an ancient vegetable that is thought to have been cultivated almost 4,000 years ago in the Near East. Both the Greeks and Romans thought highly of the turnip and developed several new varieties. Its widespread popularity in Europe has continued, although since the advent of the potato, it is less widely cultivated than it once was.

Turnips were introduced into North America by the early European settlers and colonists. They grew well in the South and became a popular food in the local cuisine of this region. Turnip greens, which became an integral part of Southern African-American cuisine, are thought to have been adopted into this food culture because of the role they played during the days of slavery. Supposedly, the slave owners would reserve the turnip roots for themselves, leaving the leaves for the slaves. As Western African cuisine traditionally utilizes a wide variety of green leaves in its cooking, the African slaves adopted turnip greens as a substitute and incorporated them into their foodways.

How to Select and Store

Turnip greens are usually available with their roots attached. Look for greens that are unblemished, crisp, and deep green in color.

If you have purchased turnip greens with roots attached, remove them from the root. Store root and greens in separate plastic bags, removing as much of the air from the bags as possible. Place in refrigerator where the greens should keep fresh for about 4 days.

Tips for Preparing and Cooking

Tips for Preparing Turnip Greens

Rinse turnip greens under cold running water. Chop greens into 1/2-inch slices for quick and even cooking.

To get the most health benefits from turnip greens, we recommend letting them sit for a minimum of 5 minutes before cooking. Sprinkling with lemon juice before letting them sit may be able to help activate their myrosinase enzymes and increase formation of beneficial isothiocyanates in the greens.

The Healthiest Way of Cooking Turnip Greens

We recommend Healthy Steaming turnip greens for maximum nutrition and flavor. Fill the bottom of a steamer pot with 2 inches of water. While waiting for the water to come to a rapid boil, chop greens. Steam for 5 minutes and toss with our Mediterranean Dressing, which includes 1 TBS lemon juice, 1 medium clove garlic (pressed or chopped), 3 TBS extra virgin olive oil salt, and black pepper to taste . Top with your favorite optional ingredients.

How to Enjoy

A Few Quick Serving Ideas

• Serve healthy sautéed turnip greens seasoned with some soy sauce, lemon juice and cayenne pepper
• Make a simple meal with a little Southern inspiration. Serve cooked turnip greens with beans and rice.
• Healthy sauté turnip greens, sweet potatoes and tofu, and serve alongside your favorite grain.
• Use turnip greens in addition to spinach when making vegetarian lasagna.

Individual Concerns

Turnip Greens and Oxalates

Turnip greens are among a small number of foods that contain measurable amounts of oxalates, naturally occurring substances found in plants, animals, and human beings. When oxalates become too concentrated in body fluids, they can crystallize and cause health problems. For this reason, individuals with already existing and untreated kidney or gallbladder problems may want to avoid eating turnip greens. Laboratory studies have shown that oxalates may also interfere with absorption of calcium from the body. Yet, in every peer-reviewed research study we've seen, the ability of oxalates to lower calcium absorption is relatively small and definitely does not outweigh the ability of oxalate-containing foods to contribute calcium to the meal plan. If your digestive tract is healthy, and you do a good job of chewing and relaxing while you enjoy your meals, you will get significant benefits—including absorption of calcium—from calcium-rich foods plant foods that also contain oxalic acid. Ordinarily, a healthcare practitioner would not discourage a person focused on ensuring that they are meeting their calcium requirements from eating these nutrient-rich foods because of their oxalate content. For more on this subject, please see "Can you tell me what oxalates are and in which foods they can be found?"

Turnip Greens as a "Goitrogenic" Food

Turnip Greens are are sometimes referred to as a "goitrogenic" food. Yet, contrary to popular belief, according to the latest studies, foods themselves—turnip greens included—are not "goitrogenic" in the sense of causing goiter whenever they are consumed, or even when they are consumed in excess. In fact, most foods that are commonly called "goitrogenic"—such as the cruciferous vegetables (including turnip greens, broccoli, kale, and cauliflower) and soyfoods—do not interfere with thyroid function in healthy persons even when they are consumed on a daily basis. Nor is it scientifically correct to say that foods "contain goitrogens," at least not if you are thinking about goitrogens as a category of substances like proteins, carbohydrates, or vitamins. With respect to the health of our thyroid gland, all that can be contained in a food are nutrients that provide us with a variety of health benefits but which, under certain circumstances, can also interfere with thyroid function. The term "goitrogenic food" makes it sound as if something is wrong with the food, but that is simply not the case. What causes problems for certain individuals is not the food itself but the mismatched nature of certain substances within the food to their unique health circumstances. For more, see an An Up-to-Date Look at Goitrogenic Substances in Food.

Nutritional Profile

Turnip greens are an excellent source of vitamin K, vitamin A (in the form of beta-carotene), vitamin C, folate, copper, manganese, dietary fiber, calcium, vitamin E, and vitamin B6. They are a very good source of potassium, magnesium, pantothenic acid, vitamin B2, iron, and phosphorus. Additionally, they are a good source of vitamin B1, omega-3 fatty acids, niacin, and protein.

For an in-depth nutritional profile click here: Turnip Greens.

In-Depth Nutritional Profile

In addition to the nutrients highlighted in our ratings chart, an in-depth nutritional profile for Turnip greens 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.

In-Depth Nutritional Profile for Turnip greens

References

• Ambrosone CB, Tang L. Cruciferous vegetable intake and cancer prevention: role of nutrigenetics. Cancer Prev Res (Phila Pa). 2009 Apr;2(4):298-300. 2009.
• Angeloni C, Leoncini E, Malaguti M, et al. Modulation of phase II enzymes by sulforaphane: implications for its cardioprotective potential. J Agric Food Chem. 2009 Jun 24;57(12):5615-22. 2009.
• Antosiewicz J, Ziolkowski W, Kar S et al. Role of reactive oxygen intermediates in cellular responses to dietary cancer chemopreventive agents. Planta Med. 2008 Oct;74(13):1570-9. 2008.
• Banerjee S, Wang Z, Kong D, et al. 3,3'-Diindolylmethane enhances chemosensitivity of multiple chemotherapeutic agents in pancreatic cancer. 3,3'-Diindolylmethane enhances chemosensitivity of multiple chemotherapeutic agents in pancreatic cancer. 2009.
• Bhattacharya A, Tang L, Li Y, et al. Inhibition of bladder cancer development by allyl isothiocyanate. Carcinogenesis. 2010 Feb;31(2):281-6. 2010.
• Brat P, George S, Bellamy A, et al. Daily Polyphenol Intake in France from Fruit and Vegetables. J. Nutr. 136:2368-2373, September 2006. 2006.
• Bryant CS, Kumar S, Chamala S, et al. Sulforaphane induces cell cycle arrest by protecting RB-E2F-1 complex in epithelial ovarian cancer cells. Molecular Cancer 2010, 9:47. 2010.
• Carpenter CL, Yu MC, and London SJ. Dietary isothiocyanates, glutathione S-transferase M1 (GSTM1), and lung cancer risk in African Americans and Caucasians from Los Angeles County, California. Nutr Cancer. 2009;61(4):492-9. 2009.
• Clarke JD, Dashwood RH and Ho E. Multi-targeted prevention of cancer by sulforaphane. Cancer Lett. 2008 Oct 8;269(2):291-304. 2008.
• Cornelis MC, El-Sohemy A, Campos H. GSTT1 genotype modifies the association between cruciferous vegetable intake and the risk of myocardial infarction. Am J Clin Nutr. 2007 Sep;86(3):752-8. 2007.
• Fowke JH, Morrow JD, Motley S, et al. Brassica vegetable consumption reduces urinary F2-isoprostane levels independent of micronutrient intake. Carcinogenesis, October 1, 2006; 27(10): 2096 - 2102. 2006.
• Higdon JV, Delage B, Williams DE, et al. Cruciferous Vegetables and Human Cancer Risk: Epidemiologic Evidence and Mechanistic Basis. Pharmacol Res. 2007 March; 55(3): 224-236. 2007.
• Hu J, Straub J, Xiao D, et al. Phenethyl isothiocyanate, a cancer chemopreventive constituent of cruciferous vegetables, inhibits cap-dependent translation by regulating the level and phosphorylation of 4E-BP1. Cancer Res. 2007 Apr 15;67(8):3569-73. 2007.
• Hutzen B, Willis W, Jones S, et al. Dietary agent, benzyl isothiocyanate inhibits signal transducer and activator of transcription 3 phosphorylation and collaborates with sulforaphane in the growth suppression of PANC-1 cancer cells. Cancer Cell International 2009, 9:24. 2009.
• Jiang H, Shang X, Wu H, et al. Combination treatment with resveratrol and sulforaphane induces apoptosis in human U251 glioma cells. Neurochem Res. 2010 Jan;35(1):152-61. 2010.
• Kelemen LE, Cerhan JR, Lim U, et al. Vegetables, fruit, and antioxidant-related nutrients and risk of non-Hodgkin lymphoma: a National Cancer Institute-Surveillance, Epidemiology, and End Results population-based case-control study. Am J Clin Nutr. 2006 Jun;83(6):1401-10. 2006.
• Konsue N, Ioannides C. Modulation of carcinogen-metabolising cytochromes P450 in human liver by the chemopreventive phytochemical phenethyl isothiocyanate, a constituent of cruciferous vegetables. Toxicology. 2010 Feb 9;268(3):184-90. 2010.
• Kunimasa K, Kobayashi T, Kaji K et al. Antiangiogenic effects of indole-3-carbinol and 3,3'-diindolylmethane are associated with their differential regulation of ERK1/2 and Akt in tube-forming HUVEC. J Nutr. 2010 Jan;140(1):1-6. 2010.
• Lakhan SE, Kirchgessner A, Hofer M. Inflammatory mechanisms in ischemic stroke: therapeutic approaches. Journal of Translational Medicine 2009, 7:97. 2009.
• Larsson SC, Andersson SO, Johansson JE, et al. Fruit and vegetable consumption and risk of bladder cancer: a prospective cohort study. Cancer Epidemiol Biomarkers Prev. 2008 Sep;17(9):2519-22. 2008.
• Li F, Hullar MAJ, Schwarz Y, et al. Human Gut Bacterial Communities Are Altered by Addition of Cruciferous Vegetables to a Controlled Fruit- and Vegetable-Free Diet. Journal of Nutrition, Vol. 139, No. 9, 1685-1691, September 2009. 2009.
• Lin J, Kamat A, Gu J, et al. Dietary intake of vegetables and fruits and the modification effects of GSTM1 and NAT2 genotypes on bladder cancer risk. Cancer Epidemiol Biomarkers Prev. 2009 Jul;18(7):2090-7. 2009.
• Machijima Y, Ishikawa C, Sawada S, et al. Anti-adult T-cell leukemia/lymphoma effects of indole-3-carbinol. Retrovirology 2009, 6:7. 2009.
• Moore LE, Brennan P, Karami S, et al. Glutathione S-transferase polymorphisms, cruciferous vegetable intake and cancer risk in the Central and Eastern European Kidney Cancer Study. Carcinogenesis. 2007 Sep;28(9):1960-4. Epub 2007 Jul 7. 2007.
• Nettleton JA, Steffen LM, Mayer-Davis EJ, et al. Dietary patterns are associated with biochemical markers of inflammation and endothelial activation in the Multi-Ethnic Study of Atherosclerosis (MESA). Am J Clin Nutr. 2006 Jun;83(6):1369-79. 2006.
• Rungapamestry V, Duncan AJ, Fuller Z et al. Effect of cooking brassica vegetables on the subsequent hydrolysis and metabolic fate of glucosinolates. Proc Nutr Soc. 2007 Feb;66(1):69-81. 2007.
• Silberstein JL, Parsons JK. Evidence-based principles of bladder cancer and diet. Urology. 2010 Feb;75(2):340-6. 2010.
• Steinbrecher A, Linseisen J. Dietary Intake of Individual Glucosinolates in Participants of the EPIC-Heidelberg Cohort Study. Ann Nutr Metab 2009;54:87-96. 2009.
• Tang L, Zirpoli GR, Guru K, et al. Consumption of Raw Cruciferous Vegetables is Inversely Associated with Bladder Cancer Risk. 2007 Apr 15;67(8):3569-73. 2007.
• Tarozzi A, Morroni F, Merlicco A, et al. Sulforaphane as an inducer of glutathione prevents oxidative stress-induced cell death in a dopaminergic-like neuroblastoma cell line. J Neurochem. 2009 Dec;111(5):1161-71. 2009.
• Thompson CA, Habermann TM, Wang AH, et al. Antioxidant intake from fruits, vegetables and other sources and risk of non-Hodgkin's lymphoma: the Iowa Women's Health Study. Int J Cancer. 2010 Feb 15;126(4):992-1003. 2010.
• Zhang Y. Allyl isothiocyanate as a cancer chemopreventive phytochemical. Mol Nutr Food Res. 2010 Jan;54(1):127-35. 2010.

• Much grattidtude to George Mateljan,and the George Mateljan Foundation for www.whfoods.com