Getting the most out of your greens


Jo Robinson, a health writer and food activist, has just published Eating on the Wild Side, a book loaded with new and interesting ideas. The fruits and vegetables we grow, buy and eat today have been made more palatable than their wild ancestors by centuries of plant breeding. This is not genetic modification, but rather the careful selection of varieties of each plant that are larger, sweeter, less bitter and easier to chew and digest. In the process, we have lost many of the important plant nutrients. Industrial farming has gone further, resulting in a loss of flavor. 

Robinson suggests many ways to find, store and cook foods to optimize their taste and nutritional value. Here are a few ideas from the book’s early chapters. 


The most intensely colored leaves have the most plant nutrients. Look for lettuce that is red, purple or reddish brown, rather than all green. The arrangement of leaves on the stem is also important, since there are fewer plant nutrients in tightly packed leaves—as in iceberg or romaine—than in loose-leaf varieties. Leaves need sunlight, and the more they are exposed to the sun, the more they make anti-oxidants to protect themselves against UV light. We absorb these compounds, which help defend against disease. 

Buy the freshest lettuces you can: packaged salad greens have been in transit longer than a heavy head of loose-leaf lettuce with crisp leaves. If you do buy packaged greens, look for a mixture of dark greens that include some spicy ones, such as arugula, mustard greens or radicchio, and look for the most distant “use by” date. 

When you get your salad greens home, Robinson suggests you tear off the leaves, rinse them, and soak them for 10 minutes in very cold water. This will lower their temperature and slow the aging process. Dry them with a towel or salad spinner. Then tear the leaves into smaller pieces, which she says will double their antioxidant value. The plant reacts as if it was being gnawed by a predator and produces a burst of nutrients to ward off the intruding insect. You should eat the leaves within a day or two after tearing them. 

If this seems like a lot of work, here is an easier approach. Put greens in a plastic bag, squeeze out the air, seal the bag, and use a needle or pin to prick the bag with 10 to 20 evenly spaced holes. Put the bag in the crisper section of your fridge. The tiny pinpricks will provide the most ideal level of humidity in the bag and enable the leaves to consume oxygen and give off carbon dioxide. The leaves will stay alive, and fresher, for longer. (And mark these bags so you can reuse them later.) Robinson likes this storage technique for many fruits and vegetables.


Arugula, a member of the cabbage family, is exceptionally high in plant nutrients and should be a regular ingredient in salads. Look for younger plants with shorter leaves if you find it too peppery. Use it as a spinach substitute in stir-fry dishes. Robinson warns that the healthful, anti-cancer properties of arugula can be lost if the leaves are boiled. 


This vegetable comes from the cardoon, a plant native to North Africa, and was cultivated during the Middles Ages as food and medicine. It is high in silymarin, a compound isolated from the milk thistle and used in alternative medicine for liver disease. An intravenous form of silymarin has been used Europe in the treatment of mushroom poisoning. 

Robinson says they have the highest antioxidant capacity of all fruits and vegetables. They are also a source of inulin, a fibrous substance that nourishes good gut bacteria. Buy the freshest artichokes you can find and use them right away. Steam them stem side down for 50 to 60 minutes for maximum nutrient retention. Artichoke hearts in glass jars are also a healthy choice.


People have been gathering wild asparagus, another vegetable high in anti-oxidants, since ancient times. The wild plant is somewhat bitter, but still popular in Italy today. Like artichokes, asparagus is high in inulin. Buy purple asparagus if you can find it, keep it cold and eat it the day you get it. Steam it for four to five minutes, and eat it with a dressing made of equal parts of orange juice, vinegar and olive oil.


Avocados, native to Central America, originated on tall trees as fruits half the size of an egg and have been cultivated for 8,000 years. They are an excellent source of antioxidants, Vitamin E, B vitamins, potassium and magnesium. Hass avocados are ripe when soft at the top with only a little give in the middle. Ripen them in a paper bag at room temperature; adding a banana to the bag will hasten ripening. If you don’t eat the whole avocado, keep the stone in and squirt with lemon juice, then cover to keep out the air. Robinson suggests another way to store half-eaten avocados: Chop half an onion and put the pieces in the bottom of a small container (preferably glass). Place the avocado half (with pit) skin-side down on the onion, cover with a lid and refrigerate. Even though the cut side of the avocado is not touching the onion, the gases will prevent browning.

A final note about tomatoes: Robinson recommends the smallest you can find, for both flavor and lycopene content. A new tomato, called a currant tomato, is close to the earliest tomatoes found in the Andes and is a real winner. 


Sadja Greenwood, a Bolinas resident, is a retired physician formerly active in Planned Parenthood and the University of California, San Francisco. Read more of her work at