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Spinach is a mild-flavored vegetable with succulent leaves that are deep green and either slightly wrinkled or flat. It is thought to have originated in Persia, and by the 15th century was cultivated in gardens in Europe. In China, it has long been a popular vegetable, grown on the edges of rice paddies and called “Chinese herbs”; in India, spinach is known as “China flower.”
Spinach can have either flat or slightly crinkled leaves. It is often available as baby spinach, which is especially useful for salads. Spinach can be purchased fresh, frozen, or canned. Fresh spinach is sold in bunches or already washed and sealed in plastic bags. A number of other greens that are similar to spinach are often sold in specialty stores. These include New Zealand spinach, which comes from a different plant family.
Spinach is available year-round, but is best in fall and spring, since it grows best in cool weather.
Spinach is usually very sandy and needs thorough washing. Trim the roots and then swish the leaves in a large bowl of water. Place the spinach in a colander, change the water in the bowl, and repeat. Do this several times until the water remains clear. If the spinach is being used in a salad or is being sautéed, pat the leaves dry with paper towel or dry them in a salad spinner.
Spinach can be consumed cooked or raw. Baby spinach leaves are especially good in salads with bleu cheese, walnuts, red onions, and a vinaigrette dressing.
Spinach cooks very quickly, and doesn’t need added water. Just place it in a pan, cover, and simmer for two to four minutes until it wilts; spinach is also excellent when steamed, or it can be sautéed in olive oil with garlic for three or four minutes.
Spinach is a good addition to stews and to soups that contain beans, pasta, or potatoes, or to any kind of curry dish. Spinach can also be creamed. Cook the spinach, then purée in a food processor, adding your choice of ricotta cheese, cream sauce, or soft tofu. Add herbs, salt, and pepper, and use as a stuffing for lasagna or pasta shells, or toss with pasta or rice. Creamed spinach can also be thinned with broth or milk to make soup.
Good seasonings for spinach include fresh lemon juice, vinegar, garlic, dill, parsley, basil, nutmeg, and mushrooms.
Spinach, 1 cup (50g) (raw)
Calories: 6.6
Protein: 0.86g
Carbohydrate: 1.0g
Total Fat: 0.105g
Fiber: 0.810g
*Excellent source of: Vitamin A (2,014 IU)
*Good source of: Vitamin C (8.4mg), and Folate (58mcg)
*Foods that are an “excellent source” of a particular nutrient provide 20% or more of the Recommended Daily Value. Foods that are a “good source” of a particular nutrient provide between 10 and 20% of the Recommended Daily Value.
Diets high in insoluble fiber (found in some vegetables) are associated with protection against heart disease in both men and women.
The strong association between increased intake of beta-carotene from food and a reduced risk of lung cancer does not necessarily mean that supplementation with natural beta-carotene supplements would reduce the risk of lung cancer. Dietary beta-carotene may be a marker for diets high in certain fruits and vegetables that contain other anticancer substances that may be responsible for the protective effects. Until more is known, some doctors advise smokers to avoid all forms of beta-carotene supplementation—even natural beta-carotene.
Foods high in vitamin K, such as vegetables, typically are associated with low cancer risk. Despite the fact that the anti-vitamin K drug warfarin might reduce the risk of cancer under certain circumstances, no evidence suggests that avoidance of vitamin K (from food or from supplements) would in any way help protect against cancer.
Some, but not all, studies have reported that eating more foods rich in beta-carotene or vitamin A was associated with a lower risk of cataracts. Synthetic beta-carotene supplementation has not been found to reduce the risk of cataract formation. It remains unclear whether natural beta-carotene from food or supplements would protect the eye or whether beta-carotene in food is merely a marker for other protective factors in fruits and vegetables high in beta-carotene.
People who eat a lot of spinach and kale, which are high in lutein and zeaxanthin, carotenoids similar to beta-carotene, have been reported to be at low risk for cataracts. Lutein, zeaxanthin, and beta-carotene offer the promise of protection because they are antioxidants. It’s quite possible, however, that lutein is more important than beta-carotene because lutein is found in the lens of the eye, while beta-carotene is not. In one preliminary study, lutein and zeaxanthin were the only carotenoids associated with protection from cataracts. People with the highest intake of lutein and zeaxanthin were half as likely to develop cataracts as those with the lowest intake.
A controlled trial showed that eating a diet high in fruits and vegetables containing folic acid, beta-carotene, and vitamin C effectively lowered homocysteine levels. Healthy people were assigned to either a diet containing a pound of fruits and vegetables per day, or to a diet containing 3 1/2 ounces (99g) of fruits and vegetables per day. After four weeks, those eating the higher amount of fruits and vegetables had an 11 percent lower homocysteine level compared to those eating the lower amount of fruits and vegetables.
People who eat plenty of fruits and vegetables high in beta-carotene appear to be at lower risk for macular degeneration than people who do not eat these foods. However, another study found no association between age-related macular degeneration and intake of antioxidants, either from the diet, from supplements, or from both combined. More research is needed to reconcile these differences. In the meantime, beta-carotene-rich vegetables continue to be part of a healthful diet.
Lutein and zeaxanthin are antioxidants in the carotenoid family. These carotenoids, found in high concentrations in spinach, collard greens, and kale, concentrate in the part of the retina where macular degeneration occurs. Once there, they protect the retina from damage caused by sunlight.
Harvard researchers reported that people eating the most lutein and zeaxanthin—an average of 5.8mg per day—had a 57 percent decreased risk of macular degeneration, compared with people eating the least. On the other hand, in another study, blood levels of lutein did not correlate with the risk of macular degeneration. Lutein and zeaxanthin can be taken as supplements; 6mg per day of lutein may be a useful amount.
As expected, spinach and kale eaters have a lower risk of macular degeneration, although blood levels of lutein have not correlated with risk of macular degeneration in one trial.
Health benefits and
concerns for vegetables
Many health benefits and concerns associated with this food are applicable to other
vegetables. Read about health benefits and concerns
for vegetables for a full description.
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The information presented in Foodnotes is for informational purposes only and was created by a team of U.S. registered dietitians and food experts. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements, making dietary changes, or before making any changes in prescribed medications. Information expires March 2005.