Your body needs large amounts of dietary fiber to function properly, which qualifies it as a macronutrient. Fat, protein, carbohydrates and water also fit in this category. Of all of these, fat is the most energy-dense at nine calories per gram. Protein and carbohydrates each provide four calories per gram. Water and fiber have no calories; although fiber is a type of carbohydrate, your body can't break it down for use as energy.
Fiber, also referred to as roughage, includes a range of undigestible substances that aid with digestion. Fiber may be soluble or insoluble. Soluble varieties bind with water to form a thick liquid in your digestive system, slowing digestion for lasting satiety. Insoluble fibers do not bind with water, but add bulk to your stool. If you don't get enough fiber, you may become constipated. Over time, a low-fiber diet may lead to diverticulosis, or the development of pouches in the small intestine that trap food and may become infected. A high-fiber diet, on the other hand, can prevent diverticulosis and also reduce diabetes risk by lowering blood glucose levels.
Fiber in Food
For soluble fiber, turn to oat bran, seeds, nuts, legumes and some produce. Find insoluble fiber in wheat bran, whole grains, fruit and vegetables. Foods with especially high fiber content include boiled kidney beans at 16 grams per cup, dates at 14 grams per cup, boiled lima beans at 10 grams per cup and Asian pears at 10 grams per fruit. Other rich sources include whole-wheat spaghetti, broccoli, spinach, cereal, peaches and apples.
Fiber pills, drinks and powders don't make up for a poor diet. They may help digestion, but supplements lack the array of vitamins, minerals and phytonutrients -- or plant nutrients -- that you get with fiber-rich foods. Plus, supplements may interfere with the absorption of various drugs, including aspirin and blood thinners such as warfarin. Fiber supplements may also lower blood sugar levels, affecting any insulin medications. These supplements are usually not dangerous, but speak to your doctor before taking them.
Women should aim for 22 to 28 grams of total dietary fiber per day. Men need 28 to 34 grams. On a 2,000-calorie diet, you need about 225 to 325 grams of carbohydrates per day, or 45 to 65 percent of total calories. As for protein, eat 50 to 175 grams a day, or between 10 and 35 percent of total calories. You need 44 to 78 grams of fat per day, making up 20 to 35 percent of total calories. However, saturated fats should make up less than 10 percent of calorie intake, while trans fats should comprise less than 1 percent. Women need about 9 cups of water or non-alcoholic fluids per day, while men need roughly 13 cups. You need more water if you live in a hot climate or engage in strenuous exercise.
Articles For Your Diet
- National Agriculture Library: Macronutrients
- University of Illinois Extension: What Are Macronutrients?
- MedlinePlus: Fiber
- U.S. Department of Agriculture: USDA National Nutrient Database for Standard Reference, Release 16
- MayoClinic.com: Fiber Supplements: Safe to Take Every Day?
- MayoClinic.com: Healthy Diet: End the Guesswork with These Nutrition Guidelines
- University of Maryland Medical Center: Fiber
- EatRight.org: How Much Water Do I Need Each Day?
- Oatmeal with blackberries. Bowlful of cereal. image by Monika 3 Steps Ahead from Fotolia.com