Fiber and the Glycemic Index
Following a low-glycemic diet is about managing your blood sugar so you avoid large insulin spikes throughout the day. Fiber is a natural part of this process. Along with its other weight-loss benefits, fiber helps control the rise of blood sugar in your body after a meal.
This effect is found specifically in soluble fiber, which dissolves and becomes gummy. Soluble fiber is also great at reducing cholesterol levels. Insoluble fiber, which people often consider roughage, is also beneficial. It works as an appetite suppressant, slows the rate that blood accepts the blood glucose that's formed from digested sugars and starches, prevents constipation, and decreases your risk for bowel diseases.
In some cases, diabetics have been able to come off of medication because a high-fiber diet was enough to control their blood sugar. Additionally, The New England Journal of Medicine noted that diabetics who ate about 50 grams of fiber had much improved blood sugar control. Pretty impressive for a food you don't even digest, huh?
Clearly fiber is an important part of your overall weight-loss plan. You should try to consume 20 to 35 grams of fiber per day, including at least one to two servings of soluble fiber. This means eating about five servings of fruits and vegetables, three servings of whole grains, and one serving of legumes each day.
Following are some specific foods that are high in both soluble and insoluble fiber (be sure to add ’em to your shopping list):
Soluble-fiber foods: Beans, peas, oats, barley, flaxseeds, and many fruits and vegetables (such as apples, oranges, and carrots).
Insoluble-fiber foods: Whole-wheat bread or pasta, corn bran, and many vegetables (such as green beans, cauliflower, and potatoes). The tough, chewy texture of these foods comes from the fiber itself.
The fiber content of vegetables and fruits varies considerably. For example, applesauce doesn't give you as much fiber as an apple with the skin on. Similarly, a large bowl of salad using only Romaine lettuce has around 1 gram of fiber compared to almost 4 grams of fiber for 1 cup of boiled collard greens.
This simple fact is why aiming for a variety of fruits, vegetables, beans, and grains is the way to go.