Unlike many of their fellow cruciferous vegetables, mustard greens have not been the sole focus of many health-oriented research studies. However, mustard greens have sometimes been included in a longer list of cruciferous vegetables that have been studied as a group in relationship to their health benefits.
Antioxidant Benefits from Mustard Greens
Although you might not typically expect a very low-fat food like mustard greens—which contain only 2/3 gram of fat in one cooked cup—to be an excellent source of fat-soluble antioxidant vitamins, mustard greens are our 5th best source of vitamin A (in the form of carotenoids) and our 7th best source of vitamin E among all 100 of our WHFoods! (This reflects that a food is simply not required to contain a large amount of fat in order to provide ample amounts of fat-soluble vitamins.) And as our 16th best source of the antioxidant mineral manganese, as well as our 18th best source of the water-soluble antioxidant vitamin C, mustard greens are a truly excellent source of conventional antioxidant support.
This cruciferous vegetable also provides unusual amounts of numerous phenolic antioxidants. Caffeic acid and ferulic acid are two phenolic antioxidants provided in significant amounts by mustard greens as are numerous polyphenolic antioxidants. Included in this polyphenol category are the flavonoids isorhamnetin, quercetin, and kaempferol. In one study on consumption of antioxidant phenols by African-American adults living in the southeastern United States, mustard greens were singled out—along with collard greens, kale, and purslane—as the top sources of total dietary phenols.
Glucosinolate Benefits from Mustard Greens
Cruciferous vegetables are perhaps most famous as a group for their unusual sulfur content, and especially their sulfur-containing glucosinolates. Glucosinolates are unique substances that provide health benefits in and of themselves, although they are better studied as substances that can converted into closely-related molecules called isothiocyanates (ITCs). The potential for glucosinolates to get converted into ITCs is often referred to as "ITC yield," and glucosinolate-containing foods with a high ITC yield are generally regarded as being especially helpful in terms of their health benefits.
The potential health benefits from intake of ITCs are known to be wide ranging, and they include decreased risk of certain cardiovascular diseases; decreased risk of certain cancer types; and support of the digestive tract including the stomach and intestinal linings. Of special interest in research on ITCs and health is the ability of these substances to support detoxification activity in our cells. Detoxification of potentially hazardous substances is not only a key to our general health, but it is also important for lowering our risk of certain cancer types. By improving our detox capacity, we reduce our risk of problems when we are exposed to hazardous substances, including substances in our general environment as well as contaminant residues in our food. In general, strong yield of ITCs from glucosinolates in cruciferous vegetables is associated with improvement in detoxification.
It is this context that makes a recent study on cruciferous vegetables especially interesting. Included in this study were eight out of the nine cruciferous vegetables that we profile on our website: broccoli, Brussels sprouts, cabbage, cauliflower, collard greens, kale, mustard greens, and turnip greens. (The only missing WHF cruciferous vegetable in this study was bok choy.) The ITC yield from these eight vegetables was found to range widely, but in terms of total possible ITC yield and average ITC yield, mustard greens easily came out on top! This first place finish of mustard greens was impressive, since all of the eight cruciferous vegetables in the study were already known to be important sources of ITCs.
It's also worth noting that the best-studied glucosinolates in mustard greens to date are sinigrin, gluconasturtiian, and glucotropaeolin. The corresponding ITCs that are produced from these three glucosinolates are allyl-isothiocyanate (AITC), phenethyl isothiocyanate (PEITC), and benzyl-isothiocyanate (BITC), respectively.
Other Health Benefits from Mustard Greens
When a food achieves 20 total rankings of "excellent," "very good," or "good" in our WHF rating system, it is not surprising to see research on health benefits branching out into many different body systems. We would like to highlight several of those body systems in this section, beginning with the cardiovascular system. Chronic unwanted low-level inflammation and chronic unwanted oxidative stress are well-established as risk factors for several cardiovascular diseases, including atherosclerosis, in which the inflammation and oxidative stress leave the blood vessel walls too susceptible to damage. The strong antioxidant support provided by mustard greens is a natural candidate for helping lower risk of atherosclerosis, and studies on overall intake of cruciferous vegetables—including mustard greens—support this finding. The glucosinolates in mustard greens have also been shown to provide help in the regulation of blood lipid levels, including levels of total cholesterol, LDL cholesterol, and HDL cholesterol. Some of this regulation has been linked to the bile acid binding ability of fiber-related nutrients in mustard greens. Also worth noting in this context is the possibility that steamed mustard greens may provide more bile acid binding ability than raw mustard greens as observed in one recent study.
Digestive tract support also needs to be listed in this "other benefits" section on mustard greens. ITCs formed from the glucosinolates in mustard greens have been shown to support the health of cells that line both the stomach and the intestinal tract. In addition, the presence of glucosinolates from mustard greens and other cruciferous vegetables in the lower intestinal tract has been show to potentially shift the balance of bacterial populations in the lower digestive tract that may be helpful to overall gut health.
One final area of potential health benefits from mustard greens involves an area of study called "AGEs." "AGEs" is an acronym for Advanced Glycation End-Products. In the last five years along, several thousand new studies on AGEs have been published in research journals, and the potential role of AGEs in increasing the risk of chronic health problems now extends to virtually all body systems. Scientists now know that AGEs have their own unique communication/messaging system, which involves specialized cell receptors called RAGEs (Receptors for AGEs). Research has yet to uncover all of the connections between food, AGE formation, and health. But intake of cruciferous vegetables is high up on the list of dietary factors that might make excessive AGE formation less likely to occur. Recent studies on sinigrin—one of the glucosinolates provided by mustard greens—has shown the ability to interfere with AGE formation process, even though the exact mechanisms here are not yet clear. In this context, it is also interesting to note that mustard seeds have been receiving even more attention in this sinigrin-related research than the "greens" (i.e., leaves) of this cruciferous vegetable.
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
"Mustard greens" is a common name that is often used to describe a wide variety of different plants in the mustard family. You are no doubt already familiar with the mustard family of plants because the science name for this family is Brassicaceae— the brassica family. While Brassicaceae has become the most commonly used science name for this plant family, it was better known in earlier years as the Crucifereae family. As you can tell from this name, the Crucifereae family was the family of cruciferous plants. Put quite simply: the "mustard family" is the same family of plants as the brassica and cruciferous family. The multiple names for this family of plants is also why you may hear some greens and herbs being referred to as "mustards" even though they do not appear to be the same as the mustard greens that are commonly labeled that way in the produce section.
From a science perspective, three basic groups of plants are found within the mustard family: white/yellow mustards (mostly belonging to the genus/species Sinapsis alba, also sometimes called Brassica alba), brown/Indian mustards (mostly belonging to the Brassica juncea genus/species), and black mustards (belonging to the Brassica nigra genus/species). Purple/red mustards are also typically members of the Brassica juncea genus/species. Because purple and red mustard leaves are becoming more popular in many grocery stores, don't be surprised to find mustard "greens" that are actually vibrant purple or purple/red in color. Red Giant, Ruby Streaks, Purple Osaka, Garnet Giant, Japanese Red, and Scarlet Frills are varieties that you might find in your local supermarket.
Sometimes confusing in descriptions of mustard are descriptions of the condiment that is made from mustard seeds. For example, you might hear descriptions like "Indian mustard, "Chinese mustard," or "German mustard." While these descriptions might refer to the genus/species of plant, they might also simply refer the way in which the condiment was made.
History
While many histories of mustard greens place their origins in parts of Europe, there is no universal agreement about the origins of this plant family, which fairly quickly became widely dispersed worldwide. The Brassica juncea genus/species of this plant is usually divided into three or four subspecies, which all have deep historical roots in parts of India and China. Today, it is common to find mustard greens throughout Europe, Northern Africa, India, and Asia, as well as North America.
Data on the production of mustard greens can be confusing since commercial cultivation of mustard plants has typically been focused more on seeds than on leaves. Canada, Nepal, Myanmar, Russia, the Ukraine, China, the United States, France, the Czech Republic and Germany were the Top 10 producers of mustard seeds in 2015.
Because mustard greens are a cool season crop, their production in the United States has usually focused on the northwest and upper Midwest regions of the country. States with a strong traditional involvement in mustard production include North Dakota, Montana, Idaho, Washington, and Oregon. Compared with many other cruciferous vegetables, mustard greens do not enjoy a large number of planted acres. Some reports show the total planted acreage for this plant to be less than 25,000 per year. By comparison, total planted acreage for broccoli is typically over 125,000.
How to Select and Store
Purchase mustard greens that are unblemished and free from any yellowing or brown spots. They should look fresh and crisp and be a lively green color.
At WHFoods, we encourage the purchase of certified organically grown foods, and mustard greens are no exception. Repeated research studies on organic foods as a group show that your likelihood of exposure to contaminants such as pesticides and heavy metals can be greatly reduced through the purchased of certified organic foods, including mustard greens. In many cases, you may be able to find a local organic grower who sells mustard greens but has not applied for formal organic certification either through the U.S. Department of Agriculture (USDA) or through a state agency. (Examples of states offering state-certified organic foods include California, New York, Oregon, Vermont, and Washington.) However, if you are shopping in a large supermarket, your most reliable source of organically grown mustard greens is very likely to be mustard greens that display the USDA organic logo.
Place mustard greens in a plastic bag, removing as much of the air from the bag as possible. Store in the refrigerator where they should keep fresh for about three to four days.
Here is some background on why we recommend refrigerating mustard greens. Whenever food is stored, four basic factors affect its nutrient composition: exposure to air, exposure to light, exposure to heat, and length of time in storage. Vitamin C, vitamin B6, and carotenoids are good examples of nutrients highly susceptible to heat, and for this reason, their loss from food is very likely to be slowed down through refrigeration.
Tips for Preparing and Cooking
Tips for Preparing Mustard Greens
Rinse mustard greens under cold running water and cut into 1/2" slices for quick and even cooking.
The Nutrient-Rich Way of Cooking Mustard Greens
From all of the cooking methods we tried when cooking mustard greens, our favorite is Healthy Sauté. We think that it provides the greatest flavor.
Healthy SautéQuick Steaming—similar to Quick Boiling and Quick Steaming, our other recommended cooking methods—follows three basic cooking guidelines that are generally associated in food science research with improved nutrient retention. These three guidelines are: (1) minimal necessary heat exposure; (2) minimal necessary cooking duration; (3) minimal necessary food surface contact with cooking liquid.
Heat 5 tablespoons of broth (vegetable or chicken) or water in a stainless steel skillet. Once bubbles begin to form add mustard greens, cover, and Healthy Sauté for 5 minutes. Toss with our Mediterranean Dressing which includes 1 tablespoon of lemon juice, 1 medium clove garlic (pressed or chopped), 3 tablespoons of extra virgin olive oil, salt and black pepper to taste. Top with your favorite optional ingredients. One additional note on Tips for Preparing and Cooking: over the broad course of research on cruciferous vegetables, there has been some amount of debate about the role that certain preparation methods might or might not play in potential health benefits. For more information in this area, please see our article, "Can Preparation Methods Impact the Benefits of Cruciferous Vegetables?"
How to Enjoy
A Few Quick Serving Ideas
- Young mustard greens make great additions to salads.
- Serve healthy sautéed mustard greens with walnuts.
- Adding chopped mustard greens to a pasta salad gives it a little kick. One of our favorite combinations is chopped tomatoes, pine nuts, goat cheese, pasta, and mustard greens tossed with a little olive oil.
WHFoods Recipes That Feature Mustard Greens
If you'd like even more recipes and ways to prepare mustard greens the Nutrient-Rich Way, you may want to explore The World's Healthiest Foods book.
Individual Concerns
Mustard Greens and Goitrogens
You may sometimes hear mustard greens being described as a food that contains "goitrogens," or as a food that is "goitrogenic." For helpful information in this area—including our WHFoods Recommendations—please see our article What is meant by the term "goitrogen" and what is the connection between goitrogens, food, and health?.
Nutritional Profile
Mustard greens are an excellent source of many vitamins including vitamin K, vitamin A (in the form of beta-carotene), vitamin C and vitamin E. They are also an excellent source of the minerals copper, manganese and calcium. They are a very good source of dietary fiber, phosphorus, vitamin B6, protein, vitamin B2 and iron as well as a good source of potassium, vitamin B1, magnesium, niacin, pantothenic acid and folate.
In the phytonutrient category, mustard greens are a valuable source of glucosinolates, including sinigrin, gluconasturtiian, and glucotropaeolin. They also provide the phenolic acids caffeic and ferulic acid, as well as the flavonoids isorhamnetin, quercetin, and kaempferol.
