The recommended daily intake of fiber is 25 grams per day for women and 38 grams per day for men. However, some experts estimate as much as 95 percent of the population don’t ingest this much fiber.
While it appears most people fall short of their recommended fiber intake, it’s actually possible to have too much fiber, especially if you increase your fiber intake very quickly. Too much fiber can cause:
- abdominal pain
- loose stools or diarrhea
- temporary weight gain
- intestinal blockage in people with Crohn’s disease
- reduced blood sugar levels, which is important to know if you have diabetes
Call your doctor right away if you’re experiencing nausea, vomiting, a high fever, or a complete inability to pass gas or stool.
If you ate too much fiber and are experiencing the symptoms of too much intake, try the following to help counteract the effects:
- Drink plenty of water.
- Stop using any fiber supplements.
- Avoid high-fiber foods.
- Eat a bland diet.
- Remove fiber-fortified foods from your diet.
- Look for foods that contain substances such as inulin and chicory root extract.
- Engage in light physical activities, like walking, as often as possible.
- Consider keeping an online diary of your food intake to help you see how much fiber you’re getting each day.
- Consider following a low FODMAP diet if you have irritable bowel syndrome (IBS). This temporary diet can improve symptoms by removing fermentable, fibrous foods from your diet.
Once you start feeling better, you should slowly re-introduce fiber-rich foods into your diet. Instead of eating fiber-rich foods in one meal, spread them out throughout the day. It’s best to get your fiber from a variety of foods, so don’t rely on any one food or source. Aim for a wide range of fruits, vegetables, whole grains, beans, and nuts.
The recommended minimum daily fiber intake depends on your gender and age.
Adult fiber intake
|Adults (50 years or younger)||Adults (over 50)|
|men||38 g||30 g|
|women||25 g||21 g|
Child and adolescent fiber intake
|Daily fiber intake|
|children 1 to 3 years||19 g|
|children 4 to 8 years||25 g|
|children 9 to 13 years||26 g (female), 31 g (male)|
|adolescents 14 to 18 years||26 g (female), 38 g (male)|
Taking in more fiber than your recommended daily intake can cause unwanted symptoms like those listed above.
There are two main types of fiber. Each type of fiber plays a different role in digestion:
- Insoluble fiber adds bulk to your stool and helps food pass more quickly through the stomach and intestines. It also helps balance the pH in your intestine, and may prevent diverticulitis, an inflammation of the intestine, as well as colon cancer.
- Soluble fiber attracts water and forms a gel-like substance with food as it’s digested. This in turn slows down digestion and helps you feel full faster, which is important in weight management. It may also help lower your risk of heart disease, regulate your blood sugar, and help reduce LDL cholesterol.
Fermentable fibers can be from both these categories, though more often soluble fibers are fermented. Fibers fermented by bacteria help increase the bacteria in the colon, which aids digestion. It also plays a major role in human health.
While too much fiber can have negative effects, a proper amount of fiber is important for your health. Fiber is essential for regular bowel movements, cholesterol and blood sugar management, healthy gut bacteria, and preventing chronic disease, among other functions.
In populations that eat a regular high-fiber diet of more than 50 grams of fiber per day, like rural South Africans, chronic diseases such as colon cancer are very low. This is a stark contrast to the much higher risk of colon cancer among African-Americans who eat a higher fat diet with only about 15 grams of fiber per day.
In general, it’s better to get fiber from the food you eat than from supplements. This is because high-fiber foods also have important vitamins and minerals your body needs to stay healthy.
- brussels sprouts
- flax and other seeds
- wheat bran
- vegetables like green beans and dark leafy greens
- root vegetables like carrots, beets, and radish
- fruit skins
- intact whole grains
- Jerusalem artichoke
- chicory root
Read further to learn about foods to avoid if you have IBS.
Fiber intake is a delicate balance. Though it may be better to have too much than too little, you’ll need to be cautious. Try not to make any drastic sudden changes to your fiber intake.
If you feel constipated and want to increase your fiber intake to help give you relief, add just a few grams of fiber to your diet each week from a variety of foods. Only take a fiber supplement if you don’t think you’re getting enough fiber from the foods you eat. Always be sure you’re also drinking enough water to avoid constipation or indigestion.
See a doctor if you think you’re eating too much fiber and limiting your intake hasn’t helped your symptoms. While at the doctor’s office, consider asking the following questions:
- How do I know how much fiber is in a particular food?
- Could my symptoms be caused by eating too much fiber?
- Should I take daily fiber supplements?
- How do I take a fiber supplement correctly?
- How quickly should I increase my fiber intake?
Seek medical attention as soon as possible if you’re experiencing nausea, vomiting, a high fever, or a complete inability to pass gas or stool for more than a few days.