People have been eating leafy greens since prehistoric times. But it wasn’t until the first Africans arrived in North America in the early 1600s that America got its first real tastes of dark green leafy vegetables, which they grew for themselves and their families.
Dark green leafy vegetables are great sources of nutrition. Salad greens, kale and spinach are rich in vitamins A, C, E and K, and broccoli, bok choy and mustard are also rich in many of the B-vitamins. These vegetables also contain an abundance of carotenoids-antioxidants that protect cells and play roles in blocking the early stages of cancer. They also contain high levels of fiber, iron, magnesium, potassium and calcium. Furthermore, greens have very little carbohydrates, sodium and cholesterol.
Raw leafy greens contain only about 100 calories per pound, and are packed with nutrients. Leafy greens contain substances that protect blood vessels, and are associated with reduced risk of diabetes. Greens are an excellent tool for weight loss, as they can be consumed in virtually unlimited quantities.
Leafy greens are also the most nutrient-dense of all foods, but, unfortunately are only consumed in minuscule amounts in a typical American diet. We should follow the example of our closest living relatives — chimpanzees and gorillas — who consume tens of pounds of green leaves every day.
The majority of calories in green vegetables, including leafy greens, come from protein. And this plant protein is packaged with beneficial phytochemicals. Green vegetables are also rich in folate (the natural form of folic acid), calcium, and contain small amounts of omega-3 fatty acids.
Leafy greens are also rich in antioxidant pigments called carotenoids, specifically lutein and zeaxanthin, which are the carotenoids known to promote healthy vision. Also, several leafy greens (such as kale) and other green vegetables (such as bok choy, broccoli, and brussel sprouts) belong to the cruciferous family of vegetables.
All vegetables contain protective micronutrients and phytochemicals, but cruciferous vegetables have a unique chemical composition — they contain glucosinolates, and when their cell walls are broken by blending, chopping or chewing, a chemical reaction converts glucosinolates to isothiocyanates (ITCs) — compounds with a variety of potent anti-cancer effects.
The Dietary Guidelines for Americans recommends increasing average intakes of fruits and vegetables, particularly those that provide more vitamins, minerals and fiber. Dark leafy green veggies fulfill this need. Many varieties of them are available in the American markets-the most popular are collards, turnip greens, chard, spinach and kale. Take the challenge and add a single serving of greens to your diet, and let us know how you feel.