arugula health benefits
STORY AT-A-GLANCE
Green leafy vegetables have been identified as a viable “new treatment” for fatty liver disease due to the inorganic nitrate they contain
Advanced age may contribute to the development of fatty liver disease, but more often, unhealthy eating habits, obesity and other hallmarks of metabolic syndrome are frequently responsible
In one study, mice divided into three groups and fed different diets, one including the equivalent of the “Western” mode of eating and another with the leafy green compound added, resulted in dramatically different outcomes to their health
Arugula contains cleansing properties that may counteract toxic heavy metals, pesticides and herbicides in your body, particularly in your liver, and helps prevent liver disease
Naturally present in high amounts in arugula, choline is an essential nutrient that’s especially important during fetal development, as well as for metabolism function, DNA synthesis and cleansing your liver
Fatty liver is the most common liver disease in the world, affecting as many as 40 percent of the U.S. population, according to the National Institutes of Health,1 and continues to rise dramatically. However, a recent clinical study indicates that a compound in green leafy vegetables may help prevent this condition.
Nonalcoholic fatty liver disease, or NAFLD, often progresses to other serious diseases, such as nonalcoholic steatohepatitis, or NASH, characterized by inflammation2 fibrosis — which causes lung scarring and stiffness3 — and cirrhosis, an advanced and irreversible stage of liver fibrosis.4
Liver steatosis is the medical term for fatty liver disease and the result of fat building up in your liver, but the bulk of the medical community is straightforward when they advise that reducing the amount of fat in your liver can be accomplished in three simple ways:
Losing weight
Making healthy food choices
Getting more physical exercise
Green Leafy Vegetables May Help Prevent Fatty Liver Disease
Researchers at the Karolinska Institutet in Sweden published a study in the Proceedings of the National Academy of Sciences (PNAS) that identifies green leafy vegetables as a viable "new treatment" for fatty liver disease due to inorganic nitrate, a compound that occurs naturally in green leafy vegetables. According to their report:
"Inorganic nitrate, present in green leafy vegetables, is converted in vivo to nitric oxide (NO) in a process involving symbiotic host bacteria. NO then induces key metabolic regulatory pathways to ultimately reduce oxidative stress and improve cardiometabolic functions."5
Advanced age and unhealthy eating habits contribute to obesity and Type 2 diabetes, (which is projected to affect 640 million people worldwide by 20406), which in turn contribute to the development of fatty liver disease, the study notes. However, simple dietary interventions, like eating more leafy greens, may help.
The featured study showed that the nitrite treatment reduced the degree of both metabolically induced and drug-induced fatty liver disease, but it should be noted that the research was done on mice, which nonetheless responded positively. The scientists concluded that clinical trials with humans would be useful in determining whether dietary nitrate would be helpful in the treatment and prevention of fatty liver disease.
Inorganic Nitrate: 'Key for Liver Health'
Leafy green vegetable consumption is associated with some of the most valuable aspects of health, which could be described as the absence of disease. But what foods are linked to some of the identifiers of poor health and disease?
According to Mattias Carlström, associate professor at Karolinska Institutet's Department of Physiology and Pharmacology and one of the study's senior researchers and authors, it's a Western diet rife with lots of unhealthy fats and lots of sugar, which unfortunately sums up the approach to food by too many Americans.
That said, the study entailed researchers dividing mice into three groups and feeding each group a different diet. The control group received a normal diet; the high-fat diet group was given the equivalent of the Western diet; and the third group was fed the same, only with nitrate supplementation added.
None of the scientists was surprised when the mice eating the Western diet gained both weight and fat mass and tested positive for raised blood sugar levels. Simultaneously and also not surprisingly, the markers of the nitrate-supplemented diet group were significantly lower.
"When we supplemented with dietary nitrate to mice fed with a high-fat and sugar Western diet, we noticed a significantly lower proportion of fat in the liver,"7 Carlström told Medical News Today, which reports:
"The researchers also found that the rodents that received the nitrate had lower blood pressure and better insulin sensitivity than those on a high-fat diet without nitrate. Previous research, the investigators explain, has shown that dietary nitrate boosts cell metabolism."8
Oxidative Stress Compromises Nitric Oxide Signaling and Impacts Heart Function
It's noteworthy that incorporating a higher amount of fruits and vegetables into the diets of the mice was confirmed to have a positive effect on cardiovascular function, according to the study authors. As for what compounds render leafy greens specifically beneficial, Carlström explains that most in the medical community still weren't sure, at least until the featured study. He asserts:
"We think that these diseases are connected by similar mechanisms where oxidative stress causes compromised nitric oxide signaling, which has a detrimental impact on cardiometabolic functions …
No one has yet focused on nitrate, which we think is the key. We now want to conduct clinical studies to investigate the therapeutic value of nitrate supplementation to reduce the risk of liver steatosis. The results could lead to the development of new pharmacological and nutritional approaches."9
While the researchers say more investigation is needed to determine which compounds led to positive turnarounds in the health of study subjects given leafy greens, they confirm that nitrate is "key" for both optimized liver and metabolic health. Further, there's nothing that says people can't conduct their own research by eating more leafy greens until "science" definitively makes the connection.
That said, the vegetables with the highest concentrations of inorganic nitrate include "celery, spinach, lettuce, and rocket," aka arugula, according to a 2016 study published in Molecular Nutrition & Food Research.10 For those wanting to experience the protective effects observed in the study, Carlström's recommendation is that it doesn't take huge amounts — only about 200 grams (or 7 ounces) of these vegetables per day.
Unfortunately, people don't always choose vegetables as a mainstay of their diets. In fact, most of the adult population in the U.S. fails to meet the daily recommendations for vegetable intake. The Healthy People 201011 initiative, designed to increase vegetable consumption and other healthy habits among people in the U.S., revealed that only 27.2 percent ate three or more servings of veggies per day.
Arugula, One of the Best Foods for Your Liver
This attractive leafy green is one of the most popular salad ingredients for one reason: its peppery, zesty flavor. As one of the foods scientists have identified as being excellent for your liver, it's not only readily available in stores and inexpensive for what it does for you nutritionally, but arugula is also easy to grow.
Arugula contains cleansing properties to counteract the poisoning effects of heavy metals in the system, particularly in your liver, and as a cruciferous vegetable, may also help to prevent cancer.12Additionally, according to the Linus Pauling Institute, it contains 8.2 milligrams of chlorophyll in one cup, which aids in wound healing, and more importantly, helps prevent liver disease.13
One study shows that the compounds in cruciferous vegetables like arugula may have a protective effect against lung, breast, colorectal, lung and other cancers.14 Another study shows that arugula contains quercetin, a dietary flavonoid that can increase your endurance for improved athletic performance.15
Liver Damage, Cirrhosis and Nonalcoholic Liver Disease
Research has revealed that the sharp increase in deaths attributed to cirrhosis is driven by excess alcohol consumption, including binge drinking, by young adults between the ages of 20 and 30, with the greatest increase of the disease between 2001 and 2013.16
As disturbing as the facts are, statistics also indicate that in every county throughout the U.S., death from alcohol-related liver disease nearly tripled between 1999 and 2016.17 The greatest increase was among those between the ages of 25 and 34, where alcoholic cirrhosis has become rampant.
NPR describes the experience of Elliot Tapper, a physician used to treating many different patients, but one patient's chronic symptoms included skin that was markedly jaundiced. He couldn't eat and he had difficulty breathing, but most surprising was that he was only in his mid-30s, which is much younger than most individuals diagnosed with liver disease.
"The patient was suffering from chronic liver disease. After years of alcohol use, his liver had stopped filtering his blood. Bilirubin, a yellowish waste compound, was building up in his body and changing his skin color."18
But excess drinking isn't the only cause of cirrhosis. It can also be caused by NAFLD (which by name identifies it as "nonalcoholic" liver disease), as well as obesity and hepatitis. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) describes cirrhosis as "a viral infection that causes liver inflammation and damage."19 Any of these can also contribute to liver failure and liver cancer, and men are five times more likely to develop NAFLD than women.20
In other words, individual lifestyle choices — including what you eat, your weight and your alcohol and/or tobacco use — will generally have a great impact on whether you will develop fatty liver disease. You may be encouraged to hear that alcohol-related cirrhosis of the liver can be reversed if it's caught early enough. Needless to say, your chances of reversing liver damage are far better if you quit drinking.
Low levels of chemical exposures can also wreak havoc on your liver function. Studies reveal that even small amounts of chemicals from food, medications, personal care products and in the environment can cause liver damage,21 and the damage is done through several mechanisms, even to the point of causing cancer.22
Choline to Help Prevent Fatty Liver Disease and Why Some Nitrates Are Harmful
Naturally present in some foods, choline has only been known in recent years as an essential nutrient. Choline is necessary to produce acetylcholine, an important neurotransmitter for memory, mood, muscle control, and other brain and nervous system functions, the National Institute of Health (NIH) reports.23
Further, choline is important for metabolism function, and is especially important during fetal development, as well as for DNA synthesis and cleansing your liver. Organic, pastured egg yolks are one of the best food sources of choline, but arugula is also an excellent source.
It's important to know which compounds are good for you and in what amounts. For example, the nitrates noted in leafy greens as being good for your liver are also good for your heart.24 However, the nitrates found in cured and processed meats, such as bacon, bologna and hotdogs, are known to be carcinogenic, and damage can be done by eating just 1.8 ounces of such foods per day.25
The difference involves nitric oxide, or NO, a soluble gas that functions as an important biological signaling molecule that supports normal endothelial function and protects your mitochondria. Gunter Kuhnle, professor of food and nutritional sciences at the University of Reading, U.K., asserts:
"When you eat nitrates, they are converted to nitrites by bacteria in your mouth. Once the nitrites reach the stomach's acid, they can turn into either nitric oxide [NO] or N-nitroso compounds.
N-nitroso compounds like nitrosamines are carcinogenic. What makes processed meats so ideal for forming N-nitroso compounds is that they have a combination of nitrite and proteins from the meat. And the meat's heme seems to help convert them into N-nitroso compounds."26
That liver disease can be averted with a simple dietary approach is excellent news for people who believe the condition is unavoidable because of its genetic predisposition. In fact, The Atlantic27published an article in 2011, "How Health and Lifestyle Choices Can Change Your Genetic Make-Up," with the summary, "Making healthy decisions may not be foolproof, but it could mean the difference between having a significant health issue and avoiding one."28