Most Americans aren't. The average adult only eats 15 grams of fiber per day.
Women need 25 grams of fiber per day, and men need 38 grams per day, according to the Institute of Medicine.
Closing the Fiber Gap
Eating more plant foods -- vegetables, beans, fruit, whole grains, and nuts -- is the best way and is one of the recommendations from the U.S. government's 2015 Dietary Guidelines.
These foods are all naturally rich in nutrients, including fiber, and provide all the health benefits that go along with a fiber-rich diet.
Top sources of fiber are: beans (all kinds), peas, chickpeas, black-eyed peas, artichokes, whole wheat flour, barley, bulgur, bran, raspberries, blackberries, and prunes.
Good sources of fiber include: lettuce, dark leafy greens, broccoli, okra, cauliflower, sweet potatoes, carrots, pumpkin, potatoes with the skin, corn, snap beans, asparagus, cabbage, whole wheat pasta, oats, popcorn, nuts, raisins, pears, strawberries, oranges, bananas, blueberries, mangoes, and apples.
Avoiding refined grains -- such as white flour, white bread, white pasta, and white rice -- and replacing them with whole grains is a great way to boost the amount of fiber in your diet. The Dietary Guidelines recommend at least half your grains be whole grains, but with all of the whole grain options available now, it's easy to do even better than that.
Whole foods are the preferred way to get fiber, because they also give you nutrients your body needs.
Soluble and Insoluble Fiber
All plant foods have fiber in different amounts.
Most fiber is soluble, meaning that it dissolves in water, or insoluble, meaning that it does not dissolve in water.
Soluble fiber is found in beans, peas, lentils, oatmeal, oat bran, nuts, seeds, psyllium, apples, pears, strawberries, and blueberries. Soluble fiber is linked to lowering LDL (bad) cholesterol, regulating blood sugar, and a lower risk of heart disease and type 2 diabetes.
Insoluble fiber is found in whole grains, barley, whole-grain couscous, brown rice, bulgur, wheat bran, nuts, seeds, carrots, cucumbers, zucchini, celery, green beans, dark leafy vegetables, raisins, nuts, grapes, and tomatoes. It helps keep you regular, prevents constipation, and lowers the chance of getting diverticular disease.
Foods high in fiber can also make you feel full longer and curb overeating. High-fiber foods are filling. They need more chewing, which may help you feel full faster.
Fiber is also linked to a lower risk of certain cancers such as colorectal cancer.
Meal Plan Packed With Fiber
This sample menu for a day gives you 37 grams of fiber:
- Breakfast: whole-grain bran flake cereal (5 grams of fiber), half a banana (1.5 grams of fiber), and skim milk.
- Snack: 24 almonds (3.3 grams of fiber) and a quarter cup of raisins (1.5 grams of fiber)
- Lunch: Turkey sandwich made with 2 slices of whole wheat bread, lettuce, and tomato (5 grams of fiber), and an orange (3.1 grams of fiber)
- Snack: Yogurt with half a cup of blueberries (2 grams of fiber)
- Dinner: Grilled fish with a salad of romaine lettuce and shredded carrots (2.6 grams of fiber), half a cup of spinach (2.1 grams of fiber), and half a cup of lentils (7.5 grams of fiber)
- Snack: 3 cups popped popcorn (3.5 grams of fiber)
7 Ways to Add More Fiber
- Start your day with a whole-grain cereal that has at least 5 grams of fiber. Look at the list of ingredients to be sure the whole grain (such as whole wheat, whole rye, or whole oats) is first on the list.
- Read labels and choose foods with at least a few grams of fiber per serving. A good source of fiber has 2.5-4.9 grams of fiber per serving. An excellent source has 5 grams or more per serving.
- Use whole-grain breads with at least 2-3 grams of fiber per slice for sandwiches.
- Choose whole fruit over juice. Whole fruit can have as much as twice the amount of fiber as a glass of juice.
- Toss beans into your soups, stews, egg dishes, salads, chili, and Mexican dishes. Substitute beans for all of the meat in at least one vegetarian meal per week.
- Experiment with international cuisines (such as Indian or Middle Eastern) that use whole grains and beans in main dishes.
- Snack on raw vegetables with bean dip or hummus.
It's best to boost fiber in your diet gradually and drink plenty of water, so your digestive system has time to adjust.
A good rule of thumb is to add about 5 grams of fiber per day, spread throughout the day, until you reach your goal.