When purchasing asparagus, look for freshly cut, bright-green spears, as
these are the most tender and flavorful.
Related to the lily family, asparagus has a slender green stalk with a distinctive but
elusive flavor and a mildly astringent undertone. Long revered in European cuisine, it’s
finding its way more frequently into American cooking.
Varieties
Green asparagus is the most commonly seen type. White asparagus,
which is grown underground to prevent chlorophyll from developing and turning it green, has
thicker, smoother spears. It’s harder to find, but worth the effort. A less frequently
seen variety is purple asparagus, called viola, which actually turns green during cooking.
Buying and storing tips
Asparagus can be found in the produce section of most health food
stores, specialty markets, and supermarkets. When buying asparagus, choose firm, bright green
(or pale ivory) stalks with tight tips. Wider spears are from older plants, and slender spears
from younger ones; both are tender and flavorful. Store asparagus tightly wrapped in a plastic
bag for up to three days in the refrigerator. It may also be stored standing upright, with the
stems immersed in about an inch of water and the tops covered with plastic.
Availability
The peak season for fresh asparagus lasts from February through June;
hothouse asparagus is available year-round in some regions. Asparagus is also available canned
and frozen.
Preparation, uses, and tips
Because it’s grown in sandy soil, asparagus should be washed
thoroughly to remove any dirt or grit. Snap any tough ends off and immerse the stalks in
boiling salted water. Reduce heat, simmer, and remove after about five minutes, while still
bright green. Toss with olive oil and
serve hot. Asparagus is also good in stir-fry dishes.
Nutritional Highlights
Asparagus, 3 medium spears of asparagus
(raw)
Calories: 11
Protein: 1.1g
Carbohydrate: 2.2g
Total Fat: 0.09g
Fiber: 1.0g
*Good source of: Vitamin C (6.3mg), and Folate (61mcg)
*Foods that are an “excellent source” of a particular
nutrient provide 20% or more of the Recommended Daily Value, based upon United States
Department of Agriculture (USDA) guidelines. Foods that are a “good source” of a
particular nutrient provide between 10 and 20% of the USDA Recommended Daily Value.
Nutritional information and daily nutritional guidelines may vary in different countries.
Please consult the appropriate organization in your country for specific nutritional values
and the recommended daily guidelines.
Health benefits and concerns
Asthma
Vitamin C, present in fruits and
vegetables, is a powerful antioxidant and
anti-inflammatory. This anti-inflammatory activity may influence the development of asthma
symptoms. A large preliminary study has shown that young children with asthma experience
significantly less wheezing if they eat a diet high in fruits rich in vitamin C.
Atherosclerosis
Diets high in insoluble fiber (found
in some vegetables) are associated with protection against heart disease in both men and
women.
Bruising
Many Americans eat insufficient amounts of foods containing vitamin
C; the disease caused by vitamin C deficiency, scurvy, causes easy bruising. While very few
people actually have scurvy, even minor deficiencies of vitamin C can increase the incidence
of bruising. People who experience easy bruising may want to try eating more fruits and
vegetables—common dietary sources of vitamin C.
Cancer
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.
Capillary fragility
Eating plenty of flavonoid- and
vitamin C-rich fruits and vegetables helps to support the structure of capillaries.
Cataracts
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.
High homocysteine
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.
Macular degeneration
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.
Multiple sclerosis (MS)
In one survey, researchers gathered information from nearly 400
individuals (half with MS) over three years. They found that consumption of vegetable protein,
fruit juice, and foods rich in vitamin C, thiamine, riboflavin, calcium, and potassium correlated with a decreased MS risk.
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.
Copyright © 2002 Healthnotes, Inc. All rights
reserved. www.healthnotes.com
Learn more about Healthnotes, the company.
Learn more about the authors of
Foodnotes.
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 December 2003.
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