Fiber is the part of plant food that the body cannot fully digest or absorb. Instead, it helps food move through the digestive system. On average, most Americans consume only about 16 grams of fiber per day, which is about 10 grams less than the minimum recommended intake for most people.
Although uncommon, it is possible to get too much fiber, especially in people who eat a plant-based diet such as a vegetarian, vegan, or raw food diet. If you eat a lot more than usual in a day, you can also feel sick from eating too much fiber.
Read on to learn more about the signs, effects, and treatment of too much fiber. Plus, learn how fiber affects digestion and which foods are high in fiber.
signs of too much fiber
If you consume too much fiber or increase your fiber intake too quickly, you may notice some uncomfortable side effects, such as:
- feeling too full
- constipation or diarrhea
- stomach cramps
- upset stomach
- loss of appetite
- weight gain or loss
In rare cases, a bowel obstruction or blockage may occur.
Contact your healthcare provider or seek immediate medical attention if you experience the following symptoms:
- inability to pass gas or have a bowel movement
- nausea and vomiting
- extreme bloating
- severe abdominal pain
Effects of too much fiber on digestion
There are two main types of fiber, soluble and insoluble. In addition to similar effects on digestion, each type has slightly different effects, such as:
- Soluble fiber: This type of fiber can be mixed with water and “dissolved” in water, creating a gel-like texture. Soluble fiber combines with other compounds and nutrients. This type has been linked to lowering LDL cholesterol levels, regulating blood sugar, improving bowel movements, helping with weight management, and other health benefits.
- Insoluble fiber: This type of fiber does not “dissolve” in the water, but instead acts to increase stool bulk and increase stool size. Insoluble fiber may help reduce diabetes risk, improve bowel movements, reduce colon cancer risk, and other benefits.
The primary way fiber affects digestion is by slowing it down and increasing stool bulk. Think of it as a workout for your digestive system. Fiber can absorb water and prevent some from being absorbed by the gut. This increases the size of the stool and requires the muscles in the intestines to push the stool through.
fiber health benefits
The health benefits of fiber include:
- Improve colon (large intestine) health
- Reduce the risk of colon cancer
- Reduce the risk of cardiovascular disease
- Helps lose weight and maintain a healthy weight
- Relieve constipation and diarrhea
- Reduce the risk of diabetes and help control blood sugar levels
- Promotes healthy gut flora (microbes that normally inhabit the digestive system and aid in the digestion and absorption of nutrients)
Despite the many health benefits of fiber, you can still have too much of the good stuff.
Think of a quick increase in your fiber intake, such as lifting from a 5-pound dumbbell to a 50-pound dumbbell. If all your muscles are trained to 5 lbs, it will be difficult to lift 50 lbs because it builds up so fast.
Fiber as well. If you increase fiber drastically, your digestive system is not ready and you will end up with symptoms of excess fiber such as bloating, gas and constipation.
The amount of fiber that is right for you may not be the same for others. Some studies show that increasing fiber intake can help relieve constipation in people with irritable bowel syndrome (IBS). However, another study found that reducing fiber can help increase bowel movements.
If you have questions about the amount of fiber that is right for you, contact your healthcare provider or registered dietitian for advice.
Daily Fiber Recommendations
In general, an adequate intake of fiber is 14 grams per 1,000 calories consumed per day. However, the exact recommendations may vary based on age, gender, and your medical history.
Here are the Institute of Medicine recommendations for daily fiber intake:
- 0-3 years: 19 grams of fiber per day
- 4-8 years: 25 grams of fiber per day
- Ages 9-13: 26 grams of fiber per day
- 14-18 years: 26 grams of fiber per day
- 19-50 years: 25 grams of fiber per day
- 50+: 21 grams of fiber per day
- Ages 9-13: 31 grams of fiber per day
- 14-18 years: 38 grams of fiber per day
- Ages 19-50: 38 grams of fiber per day
- Over 50: 30 grams of fiber per day
Depending on your genetics and medical history, the amount of fiber that is right for you may be higher or lower than these amounts.
There is no maximum recommendation for excess fiber content. Still, some information suggests that consuming more than 70 grams of fiber per day increases the risk of side effects.
high fiber foods
While you can get fiber in nutritional supplements and foods, it’s usually best to try to meet your nutritional needs with whole foods (no or minimal processing at all).
Most high-fiber foods contain both soluble and insoluble fiber. Some may be slightly higher in one type than the other, though.
soluble fiber foods
Foods high in soluble fiber include:
- Oatmeal and Oatmeal
- Beans and legumes
- citrus fruit
- Brussels Sprouts
- seeds, such as flaxseed
insoluble fiber foods
Foods high in insoluble fiber include:
- wheat and bran
- Beans and legumes
- green beans
- dark leafy greens, such as spinach, kale, and more
- peels, such as apple peels
- whole grains
excess fiber release
If you eat too much fiber and experience uncomfortable side effects, consider these tips to help ease your discomfort:
- Drink water.
- Avoid high-fiber foods.
- Stop taking any fiber supplements.
- Limit fiber-fortified foods.
- Take a walk; light physical activity may help stimulate bowel activity.
- Consider a food diary.
Your symptoms may go away later in the day or a few days later, depending on how much fiber you eat. When symptoms of excess fiber go away, try to avoid a large increase in fiber.
Instead, try these tips to prevent symptoms of too much fiber:
- Slowly increase your fiber intake by 1 to 2 grams per day
- Foods rich in space fiber in all meals
- Strive for a steady amount of fiber every day
- Drink more water
- A balanced intake of soluble and insoluble fiber
- exercise every day
Fiber is an important part of your diet, but finding the right balance of fiber amounts that work best for you can be tricky. If you eat too much fiber, you may experience symptoms such as bloating, gas, constipation, abdominal discomfort, and pain.
For most people, the general fiber recommendation is about 25-30 grams of fiber per day. If you have too much fiber, you can help relieve symptoms by drinking plenty of water, avoiding fibrous foods, and walking.
Too little fiber in the diet is more common for most Americans than too much. Still, it’s possible to eat too much fiber if you eat a plant-based diet or suddenly eat more fiber.
Try to get fiber from whole foods. Consider only taking supplements if you are unable to get enough fiber through your diet, or if recommended by a healthcare professional.
Frequently Asked Questions
Is it dangerous to eat too much fiber?
Eating too much fiber can lead to symptoms such as bloating, gas, abdominal pain, and constipation. In rare cases, people may experience a bowel obstruction or blockage.
What does your poop look like if you eat too much fiber?
Insoluble fiber causes and may cause larger stools. Soluble fiber mixes with water to create a gel-like texture that makes it easier to pass.
How do you track your daily fiber intake?
You can track your daily fiber intake by recording your food in a written or virtual food diary. Many apps and websites track the fiber content of foods.
Should IBS patients eat more or less fiber?
The effects of fiber may vary in patients with irritable bowel syndrome (IBS). Research shows that some people will benefit from a high-fiber diet, while others may benefit from a low-fiber diet.
The best way to determine the optimal fiber intake for you is to slowly increase or decrease your fiber and track your symptoms.
Do fiber supplements contain too much fiber?
It is best not to overuse fiber supplements. Follow dosing instructions and monitor the fiber content of the foods you eat. Get about 25 to 30 grams of fiber per day from food and fiber supplements.