Turnips are a winter vegetable, in season from October to March.
Martin Poole/Digital Vision/Getty Images
According to the South Beach Diet creator Dr. Arthur Agatston, you'll lose weight and be healthier if your diet consists of primarily lean protein, low-fat dairy products, fresh vegetables, eggs, beans, monounsaturated fats and "good" carbohydrates. Agatston defines a "bad" carbohydrate as one that is starchy, or that has a high glycemic index. Although turnips are often associated with starchy vegetables like potatoes, they are allowed on the South Beach Diet.
Carbohydrate Content of Turnips
In the initial, two-week phase of the South Beach Diet, starchy vegetables like potatoes, sweet potatoes and corn are not allowed. These are vegetables that contain a large amount of glucose stored in the form of starch, so they have a higher amount of carbohydrates per serving than other vegetables. However, the American Diabetes Association defines turnips as a non-starchy vegetable that is appropriate for people trying to control their carbohydrate intake to eat regularly. On average, a starch-rich vegetable like beets contains approximately 15 grams of carbohydrates in every 1/2- to 1-cup serving, while a comparable serving of non-starchy vegetables like turnips contains only 5 grams of carbohydrate.
A food's glycemic index is an indication of its effect on your blood sugar levels. A food with a high glycemic index -- 70 or higher -- is one that can cause a sharp spike, then a rapid decrease in your blood sugar. By contrast, foods with a low glycemic index, defined as 55 or less, are digested more slowly and can help keep your blood sugar level stable. The South Beach Diet emphasizes foods with a low glycemic index, since they make you feel fuller longer and may help prevent diabetes. Cooked turnips have a glycemic index of 72, putting them in the same category as medium-high glycemic index foods like oats or brown rice.
Eating Turnips on the South Beach Diet
In his book, "The South Beach Diet Cookbook," Agatston says that turnips are one of the vegetables that can fulfill your 4 1/2-cup daily vegetable allotment during Phase 1 of the diet program. Because turnips are allowed during the diet's first phase, they're also fine to eat during the plan's other two phases. Before including a large amount of turnips in your daily meals, be aware that they belong to the same cruciferous family of vegetables as cabbage or broccoli and can cause gas or bloating.
"New York Times" food writer and cookbook author Mark Bittman advises that turnips are best roasted, steamed, simmered or stir-fried. During Phase 1 of the South Beach Diet, try stir-frying thin slices of peeled turnip with other allowed vegetables like onions, broccoli and mushrooms in a small amount of extra virgin olive oil or canola oil. In Phases 2 and 3, eat roasted or steamed turnips as a side dish alongside brown rice or whole-wheat pasta and lean, broiled meat. Although turnips are often boiled and mashed as a substitute for mashed potatoes, avoid preparing them in this manner when you're on the South Beach Diet. Mashed root vegetables have a higher glycemic index than whole or chopped vegetables.