Turnips have a dowdy reputation on the dinner table, but when it comes to their nutritional benefit, they're superstars. Turnips are rich in vitamin C, dietary fiber, potassium and antioxidant compounds known as glucosinolates. These nutrients support the function of every one of your major organ systems and may help prevent disease. Take turnips from ho-hum to hip by roasting them with potatoes, carrots, onions and your favorite herb or serving them pureed as a side dish for chicken or steak. Just be aware that turnips belong to the same plant family as cabbages, broccoli and cauliflower, all vegetables that can cause gas in some people. According to cookbook author Mark Bittman, you can handle the problem by introducing turnips into your diet slowly, over a period of weeks.
A cup of cubed, cooked turnips provides 68 percent of the daily vitamin C requirement for a woman and 56 percent of the daily requirement for a man. Vitamin C helps keep your bones, teeth and immune system healthy. As an antioxidant, it can prevent DNA and cellular tissue damage by inhibiting free radical activity. A diet rich in vitamin C may help prevent heart disease, cancer, hypertension and osteoarthritis. The amount of vitamin C in turnips decreases the longer the vegetable is exposed to light, heat, air or water. Keep turnips in a cool, dark location and try to use them within three to four days of purchase. Choose baking, steaming or stir-frying over boiling to minimize water contact.
Each cup of cooked turnips provides 3.1 grams of dietary fiber, or 12 percent of your daily required intake of fiber. There are two types of fiber found in food -- soluble and insoluble -- and turnips contain both types, though they are an especially good source of insoluble fiber. Insoluble fiber does not break down during digestion. It can help regulate bowel movements and may lessen your risk of digestive problems like colon cancer. A high intake of soluble fiber may help prevent high blood cholesterol and diabetes. Fiber-rich diets are also linked to a lower risk of obesity, stroke, heart disease and hypertension.
Adult men and women need about 4,700 milligrams of potassium each day, and eating a cup of cooked turnips fulfills 8 percent of this requirement. Potassium is both a mineral and an electrolyte. It keeps bones healthy and activates enzymes responsible for energy metabolism. Along with sodium, it is crucial for muscle contraction and electrical impulse transmission among neurons. If your diet regularly includes potassium-rich foods like turnips, you may be less likely to suffer from kidney stones, osteoporosis, high blood pressure or stroke. Your body needs more potassium to function properly if you consume a lot of high-sodium foods. Choose low-sodium options and talk to your doctor about keeping your sodium levels within a healthy range.
Like all cruciferous vegetables, turnips contain a high concentration of glucosinolate compounds. Glucosinolates are naturally occurring plant chemicals that are broken down into two other types of compounds during digestion, indoles and isothiocyanates. The National Cancer Institute reports that, in the laboratory, indoles and isothiocyanates can slow the growth of cancerous cells and may trigger tumor cell death. There aren't many studies linking indoles and isothiocyanates directly to a decreased risk of cancer in humans, but several studies, including one published in 2001 in "The Journal of the American Medical Association," found that people who ate plenty of cruciferous vegetables like turnips had a lower risk of cancer, including breast cancer.
- Fruits & Veggies More Matters: Turnip - Nutrition, Selection, Storage
- USDA National Nutrient Database for Standard Reference: Nutrient Data for 11565, Turnips, Cooked, Boiled, Drained, Without Salt
- United States Department of Agriculture Household Commodity Fact Sheet: Turnips, Fresh
- Quite Health Technologies: Turnips, Boiled, Drained, w/o Salt
- Food.com: Kitchen Dictionary - Turnip
- Linus Pauling Institute: Cruciferous Vegetables
- National Cancer Institute: Cruciferous Vegetables and Cancer Prevention
- How to Cook Everything: Simple Recipes for Great Food; Mark Bittman
- University of Maryland Medical Center: Vitamin C (Ascorbic Acid)
- ABC News: Preserving Vitamin Content in Foods
Michelle Kerns writes for a variety of print and online publications and specializes in literature and science topics. She has served as a book columnist since 2008 and is a member of the National Book Critics Circle. Kerns studied English literature and neurology at UC Davis.