Aside from supplying conventional nutrients, all leafy greens (especially the deeply colored ones) are rich in phytonutrients, plant-manufactured compounds that deliver special health benefits.
Leafy Greens Are Power Food
All greens are low in calories. And a serving of just about any of the deeply colored ones contains your daily supply of vitamins K and A, most of your daily vitamin C, and a hefty helping of fiber, B vitamins and essential minerals.
As a class of food, leafy greens contain more nitrate than other foods. Recent research shows that dietary nitrate helps lower blood pressure, enhance cardiovascular health, and enhance athletic performance, among other benefits.
But eat greens every day to maintain these benefits; research suggests that the beneficial effects fall off rapidly if you don’t.
Kinds of Leafy Greens
I often make a game of how many different home-grown vegetables I can tuck into a soup or salad. A variety of leafy greens invariably tops my list: kales, collards, mustards, lettuces, turnips, spinach, arugula, chard, beet greens, chicories, escaroles, and cabbages.
All these leafy greens grow in my gardens and greenhouse. During the growing season, I pick wild greens: dandelions, chickweed, purslane, wild violets, nettles (cooked only!), lamb’s quarters, pigweeds, and more. I also count the leafy green herbs I grow and use in abundance, especially basil, sage, and oregano. They add depth, flavor, and beneficial phytocompounds to any dish.
Variety For Your Salad
My leafies differ from one another in many ways:
- Color: Though many do come in one or another shade of “green,” other leafy crops range in color from deep purple and fuchsia to deep red and mahogany. Some sport red, orange, or yellow veins.
- Shape (morphology): round, oval, rhomboid, heart-shaped, ferny, pointy at both ends, etc.
- Topography: Curly, deeply frilled, puckered, or dimpled, to smooth and flat.
- Texture: Soft and tender, buttery, crisp, chewy, juicy.
- Flavor: sweet, bitter, spicy, pungent, and tongue-stinging hot.
Three Families of Greens
What we commonly call “greens”--the leafy tops of cultivated plants—fall mainly into three big plant families.
- Brassicaceae (formerly known as the Cruciferae because of their cross-shaped flowers): These include the kales and collards, arugula, turnip greens, leaf broccoli, cabbages, and mustards (which include the dozens of greens that seed catalogues typically call “Asian”--mizuna and any variety ending in “choi/choy/soi”).
- Amaranthaceae: The leafy amaranths include spinach, Swiss chard, and beets. These plants contain special red or yellow/orange pigments called betalains that don’t occur in other plant families.
- Asteraceae (formerly Compositae): The aster family includes lettuce, many different kinds of endive and chicory (think frisee, Belgian endive, escarole), and dandelions.
Each of these plant families has its own concentration of certain classes of phytonutrients that affect its color and flavor—good reason to serve yourself a wide and changing variety of leafy greens.
Bitter Greens Are Better
Phytocompounds called phenols, flavonoids, isoflavones, terpenes, and glucosinolates give many greens a bitter taste. Plants produce these bitter-tasting chemicals to ward off animals that try to eat them. Some of these bitter elements are toxic in large doses so, like other animals, we’re hardwired to avoid bitter-tasting foods.
Accordingly, plant scientists have selectively bred the bitter elements out of our cultivated vegetables to make them more acceptable to consumers. But recent and ongoing research has shown that bitter phytocompounds can deliver a broad variety of health effects that help to ward off the chronic diseases associated with aging.
The good news: You can teach your palate to welcome, even enjoy, the strong, bitter flavors of greens such as endive, escarole, arugula, chopped kale, and others.
After all, think of how many of us have come to love strong black coffee, tea, and dark chocolate—all of which are rich in bitter-tasting phytonutrients that research suggests may be partly responsible for the health benefits claimed by them.