Carbohydrates represent a category of foods that supply your main source of caloric energy in the form of glucose, or blood sugar. A stable blood sugar level keeps your body and mind energized throughout the day. A sugar level that is excessively high or low can result in fatigue and mental confusion, or it can signify an underlying medical complication such as diabetes. If you are healthy or coping with a metabolic disorder, your choice in carbs can help to control sugar levels.
Basic Carbohydrate Digestion
Carbohydrates are generally grouped as sugars, starches or fiber. The basic molecular structure of each carbohydrate contains a union of carbon, hydrogen and oxygen, plus one or many sugar molecule chains. Sugars typically have a single or double sugar molecule, whereas starches have more complex molecule chains. During digestion, sugar and starch carbohydrate foods break back down into a single sugar molecule, or glucose. Fiber is the indigestible portion of a carbohydrate-containing food, and it does not break down into a glucose molecule. However, fiber does play a significant role in controlling blood sugar.
Wheat Pasta, Brown Rice, Oats and Beans
Carbohydrate foods that are high in fiber help control sugar levels because the fibrous portion of the food does not raise blood glucose, notes the Joslin Diabetes Center. However, foods with fiber also contain the other forms of carbohydrate, sugar or starch, which you have to account for in stabilizing sugar levels. The more fibrous a food, the slower your body absorbs the digested glucose, and this aids in keeping sugar levels even instead of causing rapid spikes or crashes. Whole grains, including wheat bread or pasta, brown rice, oatmeal, bran cereal and bean varieties, are fiber-rich carbohydrates.
Sweet Potatoes, Broccoli, Mushrooms, Peaches and Pears
Fresh fruits and vegetables are plentiful sources of fiber, but they also have a higher sugar or starch content. Control sugar levels with produce by choosing fresh varieties, not canned or frozen. Keep the skin on your fruits and vegetables, which is the primary source of fiber, to slow glucose absorption. Sweet potatoes are considered a starch, but this vegetable digests slower than a side of french fries. Colorful produce like broccoli, carrots, eggplant, strawberries, apples, pears and peaches digest more slowly than a packaged junk food snack such as candy, pastry or pretzels.
Carbohydrates, Glycemic Index and Sugar Levels
The glycemic index, or GI, is a carbohydrate classification system that measures how quickly your body converts a carb-containing food into pure glucose. Foods are grouped and scored as high GI, or 70 and up; medium GI, or 56 to 69; and low GI, or 55 and under. The low GI foods are desirable because they represent slow carbs, which they take longer to absorb and do not cause a rapid spike in sugar levels. The GI can help in controlling sugar levels, but it does not tell you the amount of carbohydrate or fiber in the item. And it also doesn't account for the ripeness, preparation, processing and foods eaten with the item, which also impact sugar level stabilization.
Considerations
Choose the majority of your carbohydrates from fresh produce and whole grains instead of from packaged, processed foods that are low in fiber and might contain added sugars. Follow a basic healthy diet, which emphasizes lean forms of protein and healthy, low-fat carbohydrates. Limit your meal portions by eating smaller, frequent meals and snacks throughout the day to sustain your energy level from glucose. Consult your physician if you have a medical condition that warrants a specific diet.
References
- Cleveland Clinic: Carbohydrates and Blood Sugar Control for People with Diabetes
- MayoClinic.com; Diabetes Diet: Create Your Healthy-Eating Plan; September 2010
- Joslin Diabetes Center: How Does Fiber Affect Blood Glucose Levels?
- Harvard School of Public Health: Carbohydrates - Good Carbs Guide The Way
- Linus Pauling Institute, Oregon State University; Glycemic Index and Glycemic Load; Jane Higdon, Ph.D.; 2005
- Glycemic Index Foundation: What Is the Glycemic Index?
