Why You Need Leafy Green Vegetables

Anyone who’s ever read a book about nutrition has come across the term “leafy green vegetables.” You might even be tired of hearing the term so much, but there’s many good reasons for why it comes up in almost every conversation about nutrition and health. Here’s a quick rundown of what a leafy green vegetable is, why it matters, and how to add more to your menu. 

Why We Need Leafy Greens

Leafy greens are an essential part of a healthy diet, not only because they’re packed with vitamins, minerals, and fiber but also because they contain many phytochemicals vital to good health. The nutrients and other chemical substances found in plants reduce the risk of health conditions, including obesity, heart disease, high blood pressure, and the vision and cognitive problems associated with aging. A diet rich in plants may also decrease the risk of certain cancers. If you still need another reason to dig into some of these vegetables, consider that they have a very high Antidepressant Food Score, a nutrient profiling system created to inform dietary recommendations concerning mental health.

Nutrients in Leafy Greens

According to the Centers for Disease Control and Prevention (CDC), powerhouse fruits and vegetables are most strongly associated with reduced chronic disease risk. These foods provide, on average, 10% or more of 17 qualifying nutrients (potassium, fiber, protein, calcium, iron, thiamin, riboflavin, niacin, folate, zinc, and vitamins A, B6, B12, C, D, E, and K). Powerhouse fruits and vegetables include green leafy vegetables, yellow/orange vegetables and fruits, citrus fruits, and cruciferous vegetables. Leafy green vegetables that are designated as powerhouses include (in order of nutrient density scores from highest to lowest): watercress, Chinese cabbage, chard, beet greens, spinach, chicory, leaf lettuce, romaine lettuce, collard greens, turnip greens, mustard greens, endive, kale, dandelion greens, arugula, and cabbage. 

Folate (vitamin B9)Synthesis and repair of DNA

Formation of red and white blood cells in bone marrow
IronRed blood cell function

Activity of myoglobin (oxygen reservoir within muscle)

Blood and respiratory transport of oxygen and carbon dioxide

Cellular respiration and energy production

Immune function

Cognitive performance
MagnesiumCofactor for more than 300 enzymes involved in the metabolism of food, synthesis of fatty acids and proteins, and other essential metabolic functions

Associated with higher bone density

Learning and memory

Neuromuscular transmission and activity (working with calcium) 
ManganeseFormation of connective and skeletal tissues

Growth and reproduction

Proper metabolism of amino acids, proteins, and lipids

Catalyzes detoxification of free radicals

May protect against some types of cancer
PotassiumMaintenance of normal water balance and acid-base balance

Regulation of neuromuscular activity

Promotes cellular growth

Muscle formation
Vitamin ANormal cell differentiation

Growth and development

Immune functions


Vitamin CAntioxidant – protecting the body against oxidative stress

Deficiency leads to immune issues

Proper lung function, especially in asthma

Synthesis of collagen and carnitine

Improves iron absorption
Vitamin EAntioxidant – protecting the body against oxidative stress
Vitamin KBone health

Blood clotting

Prevention of heart disease

Regulation of inflammation

What other beneficial compounds are in leafy green vegetables?

  • Kaempferol – may slow cognitive decline and decrease cancer risk
  • Lutein – protects the eyes from oxidation and may reduce the risk of certain cancers (colon, breast, lung, and skin)
  • Nitrates – lower blood pressure;  prevent heart disease, stroke, and pulmonary hypertension, and potentially alleviate gastric ulcers
  • Organosulfuric compounds – may fight cancer cell growth and help treat arthritic joints
  • Prebiotics – improves gastrointestinal health and immune function 

I’m sick of the same old salads. How else can I add these leafy green vegetables to my meals? 

According to the Dietary Guidelines for Americans 2020-2025, children and adults on a 2,000 calorie diet should consume 1 ½ cups of dark green leafy vegetables each week. Only 20% of people over the age of one meet the dietary goal for dark green vegetables. Some good advice stands the test of time – eat your vegetables!


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