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Verywell / Alexandra Shytsman
Dark leafy green vegetables are all the rage among health-conscious eaters. But the fact is that few of us meet the minimum USDA recommendations for the intake of these nutritional powerhouses.
So what makes a vegetable a "powerhouse" vegetable? According to a report published by the Centers for Disease Control, a powerhouse vegetable is one that supplies on average, 10% or more of the daily value of 17 qualifying nutrients per 100 calories.
The top-rated green powerhouse vegetables are watercress, chard, beet greens, spinach, and chicory. But other vegetables are also strong contenders, including Chinese cabbage, collard greens, kale, and leaf lettuce. Understanding the health benefits of dark green vegetables may help inspire you to up your intake.
The amount of dark green vegetables that you should consume depends on your age, gender, and physical activity level. As a general rule, three cups of dark green vegetables per week can help to improve your diet. But you don't even need to eat that much to meet the guidelines.
Recommended Intake of Dark Green Vegetables | |
---|---|
Children | 1/2 cup to 1 1/2 cups per week |
Adult Women | 1 1/2 cups per week |
Adult Men | 1 1/2 to 2 cups per week |
Dark green vegetables deliver a bonanza of vitamins, minerals, and phytonutrients. Dark green leafy vegetables are among the most nutritious.
But almost any veggie that is dark green in color will add value to your diet. The family of dark green leafy vegetables delivers many nutrients, such as vitamin A, vitamin C, antioxidants, fiber, folate, vitamin K, magnesium, calcium, iron, and potassium.1
Unless you top your dark green vegetables with butter or cheese, they are likely to be the least caloric food on your plate. For example, a full cup of spinach provides only seven calories. A cup of kale provides about 33 calories and a cup of broccoli contains just over 30 calories.
If you are trying to reach or maintain a healthy weight, green leafy vegetables or dark green vegetables allow you to eat more and weigh less.
It's not just the low-calorie count that matters when you consider the benefits of green veggies—it's where those calories come from that's significant. These vegetables provide complex carbohydrates, fiber, protein, and very little (if any) fat.
A cup of spinach provides just over one gram of carbohydrate, mostly from fiber. You'll also get a gram of protein.
A cup of broccoli provides about six grams of carb, 2.4 grams of fiber, and over 2.5 grams of protein.
This macronutrient balance, particularly the fiber and protein, provides a sense of long-term satiety—satisfaction and fullness—that starchier vegetables and other foods may not provide.
Those following a low-carb eating program will find that dark green leafy vegetables are particularly beneficial. These greens contain very little carbohydrate and the carbs are packed in layers of fiber; thus, they are very slow to digest.
Dark green veggies are a rich source of minerals including iron, calcium, potassium, and magnesium. They also provide important vitamins, including vitamins K, C, E, and many of the B vitamins.
Many dark green vegetable varieties of phytonutrients including beta-carotene, lutein, and zeaxanthin, which protect our cells from damage and our eyes from age-related problems, among many other effects. Dark green leaves, like kale, even contain small amounts of omega-3 fats.
Vitamin K is a fat-soluble vitamin, and it is a key nutrient in many dark green vegetables.
According to government sources, one of the most common sources of vitamin K in the U.S. diet is spinach (along with broccoli and iceberg lettuce). Other green leafy sources of vitamin K are collards, kale, and turnip greens.2
Recent research has provided evidence that this vitamin may be even more important than we once thought and many people do not get enough of it.
Vitamin K:
Those who take blood thinners need to eat consistent amounts of vitamin K each day. They should also notify their health care providers before incorporating more greens into their diet.
Studies have shown that increasing your intake of green leafy vegetables may help prevent certain diseases. A study published in the journal Neurology found that a diet containing one serving of green leafy vegetables per day is associated with slower age-related cognitive decline.
A large meta-analysis showed that the consumption of green leafy vegetables including cruciferous vegetables significantly reduces the incidence of cardiovascular disease.
And one study even showed that increasing your intake of green leafy vegetables may improve the effectiveness of omega-3 supplements in certain populations, although researchers acknowledged that more research is needed to confirm the benefit.
There are countless varieties of both dark green and dark green leafy vegetables to choose from. To boost variety in your diet, try to experiment and consume different types and different preparation methods.
Consider these three ways to add leafy greens to your diet:
Consuming more dark green leafy vegetables is easy, inexpensive, and simple if you do a little bit of advance planning. Try adding them to to to three meals per week to begin, then add a few more as you find recipes and varieties that you enjoy.