Tasty Tuesday by Anna Grindeland, RD, CD: What's the big deal about FIBER?
FIBER comes from the supporting structures of a plant such as the leaves, stems, and seeds. Some fibers play other protective roles in plants, for example, retaining water to keep plants from drying out. DIETARY FIBERS (the ones you eat) are an ESSENTIAL NUTRIENT, meaning that we must get them from the food we eat. They are often divided into two functional categories: SOLUBLE and INSOLUBLE, although most fruits, vegetables, and grains contain combinations of many different kinds of fiber.
SOLUBLE FIBERS are plants fibers that dissolve in water to form gels, slowing digestion to make you feel fuller for longer. PECTIN, one of the many soluble fibers, is used in making jams but is also naturally found in many fruits including apples, grapes, and plums. Pectin binds to lipids and bile acids to increase their excretion, thereby lowering serum cholesterol. BETA GLUCANS, like those found in oats, shiitake mushrooms, and dates are also known to decrease serum cholesterol.
INSOLUBLE FIBERS do not dissolve in water but instead, increase the water-holding capacity of feces, decreasing gut transit time—This means that make you have "to go," which is part of why eating insoluble fibers is known to decrease the risk of colon and other cancers. Insoluble fibers such as cellulose, lignin, and hemicellulose are found in the outer layer of whole grains (the bran), the strings of celery, and the hulls of seeds (think sunflower and flax seeds).
Women should aim for 25 grams of fiber per day, while men should target 38 grams (OR 21 and 30 grams daily, respectively, for those over the age of 51).
Seem like a lot? Here are some great sources of Fiber to add to your plate today:
- 1 large pear with skin (7 grams)
- 1 cup fresh raspberries (8 grams)
- 1/2 medium avocado (5 grams)
- 1 ounce almonds (3.5 grams)
- 1/2 cup cooked black beans (7.5 grams)
- 3 cups air-popped popcorn (3.6 grams)
- 1 cup cooked pearled barley (6 grams)
A word from the Academy of Nutrition and Dietetics on Fiber Supplements:
"Before you reach for the fiber supplements, consider this: fiber is found naturally in nutritious, whole foods. Studies have found the same benefits, such as a feeling of fullness may not result from fiber supplements or from fiber-enriched foods. If you're missing out on your daily amount of fiber, you may be trailing in other essential nutrients as well. Your fiber intake is a good gauge for overall diet quality. Try to reach your fiber goal with whole foods so you get all the other benefits they provide."
Source: The Academy of Nutrition and Dietetics (www.eatright.org)