8/18/2019 Asparagus Nutritional Profile

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Storing This Food

Store fresh asparagus in the refrigerator. To keep it as crisp as possible, wrap it in a damppaper towel and then put the whole package into a plastic bag. Keeping asparagus cool helpsit hold onto its vitamins. At 32°F, asparagus will retain all its folic acid for at least two weeks

and nearly 80 percent of its vitamin C for up to five days; at room temperature, it would loseup to 75 percent of its folic acid in three days and 50 percent of the vitamin C in 24 hours.

Preparing This Food

The white part of the fresh green asparagus stalk is woody and tasteless, so you can bendthe stalk and snap it right at the line where the green begins to turn white. If the skin is verythick, peel it, but save the parings for soup stock.

What Happens When You Cook This FoodChlorophyll, the pigment that makes green vegetables green, is sensitive to acids. Whenyou heat asparagus, its chlorophyll will react chemically with acids in the asparagus or inthe cooking water to form pheophytin, which is brown. As a result, cooked asparagus isolive-drab.

 You can prevent this chemical reaction by cooking the asparagus so quickly that thereis no time for the chlorophyll to react with acids, or by cooking it in lots of water (whichwill dilute the acids), or by leaving the lid off the pot so that the volatile acids can float offinto the air.

Cooking also changes the texture of asparagus: water escapes from its cells and theycollapse. Adding salt to the cooking liquid slows the loss of moisture.

How Other Kinds of Processing Affect This Food

Canning. The intense heat of canning makes asparagus soft, robs it of its bright greencolor, and reduces the vitamin A, B, and C content by at least half. (White asparagus,which is bleached to remove the green color, contains about 5 percent of the vitamin Ain fresh asparagus.) With its liquid, canned asparagus, green or white, contains about 90times the sodium in fresh asparagus (348 mg in 3.5 oz. canned against 4 mg in 3.5 oz. freshboiled asparagus).

Medical Uses and/or Benefits

 Lower risk of some birth defects. As many as two of every 1,000 babies born in the UnitedStates each year may have cleft palate or a neural tube (spinal cord) defect due to their moth-ers’ not having gotten adequate amounts of folate during pregnancy. The RDA for folate is

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400 mcg for healthy adult men and women, 600 mcg for pregnant women, and 500 mcg forwomen who are nursing. Taking folate supplements before becoming pregnant and throughthe first two months of pregnancy reduces the risk of cleft palate; taking folate through theentire pregnancy reduces the risk of neural tube defects.

 Lower risk of heart attack. In the spring of 1998, an analysis of data from the records for morethan 80,000 women enrolled in the long-running Nurses’ Health Study at Harvard School ofPublic Health/Brigham and Woman’s Hospital, in Boston, demonstrated that a diet providingmore than 400 mcg folate and 3 mg vitamin B6  daily, from either food or supplements, morethan twice the current RDA for each, may reduce a woman’s risk of heart attack by almost 50percent. Although men were not included in the analysis, the results are assumed to apply tothem as well.

However, data from a meta-analysis published in the  Journal of the American Medical Association in December 2006 called this theory into question. Researchers at Tulane Univer-sity examined the results of 12 controlled studies in which 16,958 patients with preexistingcardiovascular disease were given either folic acid supplements or placebos (“look-alike” pillswith no folic acid) for at least six months. The scientists, who found no reduction in the riskof further heart disease or overall death rates among those taking folic acid, concluded thatfurther studies will be required to verify whether taking folic acid supplements reduces therisk of cardiovascular disease.

Adverse Effects Associated with This Food

Odorous urine. After eating asparagus, we all excrete the sulfur compound methyl mercap-tan, a smelly waste product, in our urine.

Food/Drug Interactions Anticoagulants. Asparagus is high in vitamin K, a vitamin manufactured naturally by bac-teria in our intestines, an adequate supply of which enables blood to clot normally. Eatingfoods that contain this vitamin may interfere with the effectiveness of anticoagulants suchas heparin and warfarin (Coumadin, Dicumarol, Panwarfin) whose job is to thin blood anddissolve clots.

Asparagus