Energy value (calories per serving): Low
Saturated fat: Low Cholesterol: None Carbohydrates: High Fiber: Moderate Sodium: Moderate
Major vitamin contribution: Vitamin C
Major mineral contribution: Potassium
About the Nutrients in This Food
Beets are roots, high-carbohydrate foods that provide sugars, starch, and small amounts of dietary fiber, insoluble cellulose in the skin, and soluble pectins in the flesh. Beets are also a good source of the B vitamin folate.
One-half cup cooked fresh beets has one gram of dietar y fiber and 68 mcg folate (17 percent of the R DA).
The Most Nutritious Way to Serve This Food
Cooked, to dissolve the stiff cell walls and make the nutrients inside available.
Diets That May Restrict or Exclude This Food
Buying This Food
Look for: Smooth round globes with fresh, crisp green leaves on top.
Avoid: Beets with soft spots or blemishes that suggest decay underneath.
Storing This Food
Protect the nutrients in beets by storing the vegetables in a cool place, such as the vegetable crisper in your refrigerator. When stored, the beet root converts its starch into sugars; the longer it is stored, the sweeter it becomes.
Remove the green tops from beets before storing and store the beet greens like other leaf y vegetables, in plastic bags in the refrigerator to keep them from drying out and losing vitamins (also see gr eens).
Use both beets and beet greens within a week.
Preparing This Food
Scrub the globes with a vegetable brush under cold running water. You can cook them whole or slice them. Peel before (or after) cooking.
What Happens When You Cook This Food
Betacyamin and betaxanthin, the red betalain pigments in beets, are water-soluble. (That’s why borscht is a scarlet soup.) Betacyanins and betaxanthins turn more intensely red when you add acids; think of scarlet sweet-and-sour beets in lemon juice or vinegar with sugar. They turn slightly blue in a basic (alkaline) solution such as baking soda and water.
Like carrots, beets have such stiff cell walls that it is hard for the human digestive tract to extract the nutrients inside. Cooking will not soften the cellulose in the beet’s cell walls, but it will dissolve enough hemicellulose so that digestive juices are able to penetrate. Cook- ing also activates flavor molecules in beets, making them taste better.
How Other Kinds of Processing Affect This Food
Canning. Beets lose neither their color nor their texture in canning.
Medical Uses and/or Benefits
Lower risk of some birth defects. As many as two of every 1,000 babies born in the United States 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 R DA for folate is
400 mcg for healthy adult men and women, 600 mcg for pregnant women, and 500 mcg for women who are nursing. Taking folate supplements before becoming pregnant and continu- ing through the first two months of pregnancy reduces the risk of cleft palate; taking folate through the entire pregnancy reduces the risk of neural tube defects.
Possible lower risk of heart attack. In the spring of 1998, an analysis of data from the records of more than 80,000 women enrolled in the long-running Nurses’ Health Study at Harvard
School of Public Health/Brigham and Women’s Hospital, in Boston, demonstrated that a diet providing more than 400 mcg folate and 3 mg vitamin B6 daily, either from food or supple- ments, might reduce a woman’s risk of heart attack by almost 50 percent. Although men were not included in the study, the results were assumed to apply to them 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 preexisting cardiovascular diseases were given either folic acid supplements or placebos (“look-alike” pills with no folic acid) for at least six months. The scientists, who found no reduction in the risk of further heart disease or overall death rates among those taking folic acid, concluded that further studies will be required to verif y whether taking folic acid supplements reduces the risk of cardiovascular disease.
Adverse Effects Associated with This Food
Pigmented urine and feces. The ability to metabolize betacyanins and be taxanthins is a genetic trait. People with two recessive genes for this trait cannot break down these red pig- ments, which will be excreted, bright red, in urine. Eating beets can also turn feces red, but it will not cause a false-positive result in a test for occult blood in the stool.
Nitrosamine formation. Beets, celery, eggplant, lettuce, radishes, spinach, and collard and turnip greens contain nitrates that convert naturally into nitrites in your stomach—where some of the nitrites combine with amines to form nitrosamines, some of which are known carcinogens. This natural chemical reaction presents no known problems for a healthy adult. However, when these vegetables are cooked and left standing for a while at room tempera- ture, microorganisms that convert nitrates to nitrites begin to multiply, and the amount of nitrites in the food rises. The resulting higher-nitrite foods may be dangerous for infants (see spinach).