Carbohydrates, proteins and fats make up the three macronutrient groups. Carbohydrates can be found in fruit, vegetables, grains, beans and legumes, dairy products and sugar. The U.S. Department of Agriculture divides the carbohydrates group into simple carbohydrates -- such as sugar, white flour and white rice, which cause a rapid rise in blood glucose levels -- and complex carbohydrates, a subgroup that includes the whole, unrefined grains, most vegetables and some fruits, which are digested more slowly.
Low-Calorie Complex Carbohydrates
Vegetables, which contain a wide variety of vitamins and minerals, are the lowest calorie source of complex carbohydrates. Nutrient-dense vegetables such as kale, spinach, asparagus, broccoli and the rough surface mushrooms can be recognized as highly nutritious carbohydrates by their bright colors and strong flavors. Eating eight or more servings of these vegetables daily along with citrus fruits -- oranges, grapefruit, limes and lemons -- can reduce your risk of a heart attack or stroke. This is largely due to the presence of anti-inflammatory compounds, but these vegetables also contribute a great deal of fiber and create a sense of fullness for the average investment of less than 100 calories per cup, and weight management reduces the risk of cardiovascular disease.
Unprocessed wheat and other grains are harvested and ground without removing any of the three separate layers: bran, the fibrous outer layer that protects the contents of a grain kernel; the endosperm, which stores energy to nourish the germ; and the germ itself, which is the reproductive kernel. The germ contains unsaturated oils as well as vitamins and minerals. When grains are stored, these oils that can cause spoilage. For this reason as well as to make grains easier to work with in various culinary uses, people began to refine flour, rice and other grains in the late 19th century. These refining processes remove many nutrients from the grain and cause them to behave more like sugars.
Healthy whole grains include quinoa, buckwheat, wheat berries, rye, corn, brown rice, hulled barley, oats, millet and teff.
Fruits contain many vitamins and minerals and are also important sources of fiber and water. Like vegetables, the variety of fruits consumed is more important than the quantity of any single fruit. Berries are among the most anti-inflammatory of foods; citrus fruits supply a great deal of vitamin C, which promotes iron absorption and prevents anemia; and apples and pears contribute the fiber and water needed to promote healthy digestive function. Having a daily serving from each of these fruit types offers a wide variety of health benefits.
Fruit juice is not a complex carbohydrate in that the fiber present in whole fruits has largely been removed from the juice. In fact, an 8-ounce glass of orange juice and an 8-ounce glass of soda contain the same 10 teaspoons of sugar, according to an analysis published by Harvard researchers.
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This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.