05/01/2025
Dietary fiber: Essential for a healthy diet
Add more fiber to your diet. Maybe you've heard that advice before. But do you know why dietary fiber is so good for your health?
Fiber is found mainly in plant foods such as fruits, vegetables, whole grains and members of the bean family called legumes. Fiber may be best known for its ability to prevent or relieve constipation. But foods with fiber can have other good effects as well. They can help you stay at a healthy weight and lower the risk of diabetes, heart disease and some types of cancer.
Choosing tasty foods that provide fiber isn't hard. Find out how much dietary fiber you need, which foods have it, and how to add them to meals and snacks.
What is dietary fiber?
Dietary fiber is a nutrient known as a carbohydrate. Fiber includes the parts of plant foods that the body can't digest or absorb. This makes it different from nutrients such as fats, proteins, and other carbohydrates including starches and sugars. The body breaks down these nutrients and absorbs them. Instead, fiber passes somewhat intact through the stomach, small intestine and colon and out of the body.
There are two main types of fiber:
Soluble fiber. This type of fiber dissolves in water. It forms a gel-like material in the stomach that slows down digestion. It can help lower cholesterol and blood sugar. Soluble fiber is found in oats, peas, beans, apples, bananas, avocados, citrus fruits, carrots, barley and psyllium.Insoluble fiber. This type of fiber doesn't dissolve in water. It supports the movement of material through the digestive system and adds bulk to stool. So it can be helpful for people who have constipation or don't regularly pass stool. Some good sources of insoluble fiber are whole-wheat flour, wheat bran, nuts, beans, and vegetables such as cauliflower, green beans, potatoes with skin and green leafy vegs like kale and spinach.
Most high-fiber plant foods contain both soluble and insoluble fiber. The amount of each type of fiber varies with the type of plant, such as whether it's a fruit, vegetable or whole grain. But you can get both types of fiber by eating a variety of fiber-rich foods.
How much fiber do you need?
The National Academy of Medicine gives the following daily fiber recommendations for adults:
25 grams for women 30 grams for men older than age 50.38 grams for men age 50 or younger.
Benefits of a high-fiber diet
A high-fiber diet may support good health in a number of ways.
High fiber and less chance of constipation
Dietary fiber increases the weight and size of stool and softens it. In general, bulky stool is easier to pass, and this lowers the chance of constipation. If you have loose, watery stools, fiber may help make them solid. That's because fiber absorbs water and adds bulk to stool.
Bowel health and fiber
A high-fiber diet may lower the risk of swollen veins in the a**s and lower re**um called hemorrhoids. Eating plenty of fiber also may help lower the risk of a condition called diverticulitis that involves small, inflamed pouches in the colon wall. A high-fiber diet is linked with a lower risk of colorectal cancer as well. Some fiber also serves as food for "good" bacteria in the gut. It's known as fermented fiber. It may play a role in lowering the risk of diseases of the colon.
High fiber and lower cholesterol levels
Soluble fiber found in beans, oats, flaxseed and oat bran may keep the body from absorbing some of the cholesterol in other foods. As a result, that may lower low-density lipoprotein, also called "bad," cholesterol levels in the blood. High-fiber foods may have other effects on heart health, such as lowering blood pressure and lessening swelling in the body called inflammation.
Blood sugar levels and fiber
In people with diabetes, fiber may slow the absorption of sugar and help improve blood sugar levels. That's especially true of soluble fiber. A healthy diet that includes both soluble and insoluble fiber also may lower the risk of type 2 diabetes.
Healthy weight and fiber
High-fiber foods tend to be more filling than low-fiber foods. So you're likely to eat less and stay satisfied longer. High-fiber foods also tend to take longer to eat and to be less energy dense than low-fiber foods. That means they have fewer calories for the same volume of food.
High-fiber diet and lifespan
Getting more fiber is linked with a lower risk of dying of any health condition, including heart disease.
Your best fiber choices
Nutritious foods that can help you get more daily fiber include:
Whole-grains such as barley, bulgur, brown rice, and whole-wheat bread or pasta.Fruits.Vegetables. Beets, green beans. Corn, carrots, this list is long! Whole Beans like red kidney or black beans, peas and other legumes.
Refined or processed foods usually are lower in fiber. The grain-refining process removes the outer coat, called bran, from the grain. That lowers the amount of fiber and other nutrients in the grain.
Examples of refined grains include white bread, pasta and cereals that aren't made with whole grains.
Tips for fitting in more fiber
Need ideas for adding more fiber to your meals and snacks? Try these suggestions:
Jump-start your day. For breakfast, choose a breakfast cereal with 5 grams or more of fiber a serving. add a few tablespoons of wheat bran , sliced bananas, berries or other fruit.Switch to whole grains. Each day, make sure that at least half of the grains you eat are whole grains. Try other whole grains, such as brown rice, wild rice, buckwheat, whole-wheat pasta and quinoa.Learn to like legumes. Beans and members of the bean family such as peas and lentils are excellent sources of fiber. Add kidney beans to canned soup or a green salad. Or make nachos with black beans, lots of fresh veggies, whole-wheat tortilla chips and salsa.Eat fruit and vegetables. They're rich in fiber as well as vitamins and minerals. Try to eat five or more servings daily. You can have fresh, frozen or canned fruits and vegetables. If you eat canned fruits, choose those that are canned in 100% fruit juice instead of syrup. If you eat canned vegetables, make sure they're low in sodium.Make snacks count. Whole fruits, raw vegetables, low-fat popcorn without salt and whole-grain crackers are all healthy choices. A handful of nuts or dried fruits that don't have added sugar also can be a healthy, high-fiber snack. Just be aware that crackers, nuts and dried fruits are high in calories. Nuts are high in fats and dried fruit super high carb so a little goes a Long Long way!
High-fiber foods are good for your health. But adding too much fiber too quickly can lead to gas, bloating and cramping. Add fiber to your diet slowly over a few weeks. This lets natural bacteria in your digestive system adjust to the change.
Also, drink plenty of water. Fiber works best when it absorbs water. This makes your stool soft, bulky and easier to pass.
