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How Much Dietary Fiber Do You Need?

Most women should get at least 25 grams and most men 38 grams each day to gain all the health benefits of fiber, according to the Institute of Medicine’s Dietary Reference Intake. The problem is that most Americans get only about half that when not on a diet and even less when dieting, especially on low-carb diets. 

Tufts University researcher and professor of nutrition Susan Roberts, PhD, has shown that people who eat 35 to 45 grams of fiber a day are less hungry when losing weight and lose more weight than people who eat less fiber. (But beware of consuming fiber as a bulk laxative; it can sap your body of needed nutrients and vitamins.)

“There is no downside to eating a diet rich in fiber,” Slavin says. “And the potential health gains are significant.”

Does Type of Fiber Affect Weight Loss?

Fibers come in a variety of forms:

  • Fiber is either soluble or insoluble: Soluble dissolves in water, insoluble does not. Both of these types are fiber are found naturally in fruits, vegetables, whole grains, legumes, and nuts.
  • “Dietary” fiber refers to the fiber found naturally in the foods that we eat.
  • “Functional” fibers such as inulin are added to packaged foods to boost their fiber content. These fibers are isolated or extracted from a plant or animal source, or they are manufactured.

Although all fiber is healthy, research indicates that fiber from whole foods may aid weight loss the most – likely because those high-fiber foods are also low in calories. 

“As a registered dietitian, I always say ‘food first,’” Slavin tells WebMD.

“No one fiber is perfect, so eating a wide variety of fibers is the perfect solution to gain all the health benefits of fiber,” Slavin says. “Not only will you trim your waistline with a high-fiber diet rich in fruits, vegetables, whole grains, legumes, and nuts, but also reduce the risk for heart disease, diabetes, obesity, diverticulitis, and constipation."

Add Fiber Calories Wisely and Slowly

Slowly adding more fiber to your diet can avoid bloating and gas by giving your body time to adapt. It is also important to drink plenty of liquids while increasing fiber.

High-Fiber Super Foods

From fruits to nuts, see the best source of fiber in natural foods.
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Dietary Fiber Poll

What provides most of your fiber?

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