What is dietary fiber?

Dietary fiber is the indigestible carbohydrate portion of plant foods. It includes soluble and insoluble forms that support digestion and metabolic health.

What are the main benefits of dietary fiber?

Fiber supports regular bowel movements, helps lower LDL cholesterol, and can improve blood sugar control. High-fiber foods may also increase fullness and support weight management.

What foods are high in dietary fiber?

Common sources include fruits, vegetables, legumes, whole grains, nuts, and seeds. Choosing minimally processed plant foods typically increases fiber intake.

How much dietary fiber do adults need per day?

General guidance is about 25–38 g per day for adults. Needs can vary by age, sex, and overall diet pattern.

Can increasing fiber cause side effects?

A rapid increase can cause gas, bloating, or changes in bowel habits. Increasing intake gradually and drinking enough fluids can help improve tolerance.

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Populaire keuzes

Eicosapentaenoic acid (EPA)Vitamin D3 Docosahexaenoic acid (DHA)Zinc (Bisglycinate)

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Vitamin B

Vitamin B1 (Thiamine)

Vitamin B2 (Riboflavin)

Vitamin B3 (Niacin)

Vitamin B5 (Pantothenic Acid)

Vitamin B6 (Pyridoxine)

Vitamin B7 (Biotin)

Vitamin B9 (Folic Acid)

Vitamin B12 (Methylcobalamin)

Vitamin B12 (Cobalamin)

Vitamin A & Carotenoids

Vitamin C

Vitamin D

Vitamin E

Vitamin K

Vitaminoids

Trimethylglycine (Betaine)

NMN (Nicotinamide Mononucleotide)

Pyrroloquinoline Quinone (PQQ)

D-Chiro-Inositol

Coenzym Q10 (Ubiquinone)

Betaine HCL

Nicotinamide Riboside

Vitamin B8 (Myo-Inositol)

Choline

Citicoline (CDP-Choline)

Coenzyme Q10 (Ubiquinol)

Calcium

Calcium Alpha-Ketoglutarate

Magnesium

Magnesium Bisglycinate

Magnesium L-Threonate

Trace Minerals

Copper (Bisglycinate)

Chromium Picolinate

Manganese (Bisglycinate)

Zinc

Pentadecanoic Acid (C15:0)

Phosphatidylserine

R-Alpha Lipoic Acid

Black Cumin Oil

Extra Virgin Olive Oil

Ceratiq wheat oil extract

Phospholipids

Algae Oil

Fish Oil

Conjugated Linoleic Acid

Gamma-Aminobutyric Acid

Alpha-Linolenic Acid

Gamma-Linolenic Acid

Omega-3

Docosapentaenoic acid (DPA)

Eicosapentaenoic acid (EPA)

Docosahexaenoic acid (DHA)

AminoMar

Acetyl-L-Carnitine

PABA (para-aminobenzoic acid)

Essential Amino Acids

Conditionally Essential Amino Acids

L-Theanine

Non-Essential Amino Acids

Beta-Alanine

L-Cysteine Hydrochloride

Amino Acid Derivative

Taurine

Creatine (Hydrochloride)

L-Arginine Alpha-Ketoglutarate

Creatine (Monohydrate)

Akkermansia muciniphila

Lactobacillus Reuteri

Probiotics

Bifidobacterium longum BB536

Prebiotics

Stinging Nettle Extract

Pomegranate Polyphenols

Red Beet Extract

Pine Extract (Pycnogenol)

Oligomeric Proanthocyanidins (OPC)

Ashwagandha Root Extract

Methylsulfonylmethane (MSM)

Citrus Sinensis Extract

Horsetail Stem Extract

Flax Seed Extract

Sulforaphane Glucosinolate

Garlic Extract

Black Pepper

Apricot Kernel Extract

Lovage

Spiny Rest Harrow Root Extract

Juniper Berry Extract

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White Kidney Bean Extract

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Hydroxytyrosol/tyrosol

Olive extract

Sesame seed lignan extract

Broccoli Sprout Extract

Cranberry Extract

Flavon Glycosides

Gentian Root Extract

Griffonia simplicifolia Extract

Ajuga Turkestanica Extract

Amaranthus Leaf Extract

Banaba Extract

Boswellia Extract

Capsaicin

Cayenne Pepper Extract

Celery Extract

Ceylon Cinnamon Extract

Chamomile Extract

Charantin

Chinese Goldthread Root Extract

Citrus Aurantium Extract

Cocoa Extract

Cyanotis Arachnoidea Extract

Fadogia Agrestis Extract

Garcinia Cambogia Extract

Goldenrod Extract

Green Tea Extract

Guarana Extract

Horse Chestnut Extract

Grapefruit Seed Extract

Grape Vine Leaf Extract

Green Tea Polyphenols

Epigallocatechin Gallate (EGCG)

Adaptogens

Cordyceps sinensis extract

Ginsenoside

Lion's Mane (Hericium erinaceus)

Ginseng Extract

Cat's Claw (Uncaria tomentosa)

Arjuna (Terminalia arjuna)

Tribulus Terrestris Extract

Rhodiola rosea

Panax Ginseng Extract

Mushrooms

Reishi Extract

Astragalus Polysaccharides

Hyaluronic Acid

Glucosamine Sulfate

Chondroitin Sulfate

Glucosamine Sulphate 2KCL

Dietary Fiber

Strong study situation·10/10

A higher score indicates better study conditions, but not necessarily effectiveness.

Dietary fiber is an essential plant-based nutrient that supports digestive, cardiovascular, and metabolic health.

Digestion & Gut Health Cardiovascular Support Essential Nutrient Glucose Metabolism Cholesterol Management Weight Management

dose range

25–38 g

Split between meals with ample fluids.

Consumption

Increase intake gradually; consume with plenty of water. Favor whole food sources over supplements when possible.

Not fat-soluble.

Best time

Best taken with meals throughout the day.

Description

Dietary fiber encompasses indigestible carbohydrates from plants, including soluble and insoluble forms, found in foods like fruits, vegetables, grains, and legumes. Fiber is vital for healthy digestion, cholesterol reduction, and blood sugar regulation.

benefits

Main effects with level of evidence

Strong

Note on evidence

Benefits of dietary fiber—particularly from whole foods—are strongly supported by epidemiological and clinical research.

Supports digestive regularity and prevents constipation

Strong

Fiber increases stool bulk and water content, promoting regular bowel movements and reducing constipation risk, especially when intake is adequate and gradual.

Particularly relevant for: general public · older adults · pregnant women

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 2 · Systematic Review: Dietary Fiber and Constipation 6 · Examine.com – Dietary Fiber 7 · Harvard T.H. Chan School of Public Health – Fiber

Helps lower cholesterol and reduce cardiovascular risk

Strong

Soluble fiber binds cholesterol in the gut, aiding in its excretion and contributing to lower LDL cholesterol and reduced risk of heart disease.

Particularly relevant for: general public · heart disease risk groups

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 5 · EFSA Panel on Dietetic Products – Scientific Opinion on Dietary Reference Values for Carbohydrates and Fiber 6 · Examine.com – Dietary Fiber 7 · Harvard T.H. Chan School of Public Health – Fiber

Improves blood sugar control

Moderate

Soluble fiber slows glucose absorption, resulting in improved blood sugar regulation and reduced type 2 diabetes risk.

Particularly relevant for: individuals with prediabetes or diabetes

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 3 · Meta-analysis: Dietary Fiber Intake and Risk of Type 2 Diabetes 6 · Examine.com – Dietary Fiber 7 · Harvard T.H. Chan School of Public Health – Fiber

Aids weight management

Moderate

High-fiber foods promote satiety and may reduce overall calorie intake, supporting weight control efforts.

Particularly relevant for: general public · individuals with overweight

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 6 · Examine.com – Dietary Fiber 7 · Harvard T.H. Chan School of Public Health – Fiber

Safety & Information

Important safety information & known risks

For educational purposes only • not medical advice

Dietary fiber is safe for most individuals, but rapid increases or excessive use may cause GI symptoms. Certain populations should exercise caution.

warning notices

Common side effects of rapid increases: bloating, gas, abdominal pain.
High-dose supplements are contraindicated in bowel obstruction or severe gut motility disorders.
Excess fiber may interfere with absorption of medications or minerals.
Avoid high-dose fiber supplements in cases of known bowel obstruction or severe gastrointestinal motility disorders.
Increase fiber intake gradually to reduce risk of bloating and gas.
Monitor for reduced absorption of certain medications when taken concurrently with fiber supplements.

Known interactions with medications

May alter absorption of diabetes or seizure medications—monitor and adjust as needed.

Contraindications / special precautions

Complete or suspected bowel obstruction
Severe gastrointestinal motility disorders

interactions

Important interactions between active ingredient ↔ supplement / medication / food

High fiber intake can affect the absorption of certain minerals and medications; some forms interact with diabetes or seizure medications.

High-dose fiber may reduce absorption of minerals like calcium, iron, zinc, and magnesium.

nutrient · Minerals

MonitorModerate

Why

Certain fiber types bind minerals in the gut, limiting absorption; impact is minor with balanced diet but notable with excessive supplemental fiber.

recommendation

Monitor mineral intake if using high-dose fiber supplements, especially in populations at risk for deficiencies.

Fiber supplements may alter absorption of oral diabetes medications.

drug · Diabetes medications

AdjustLimited

Why

Some fibers slow carbohydrate and thus medication absorption, affecting glycemic control.

recommendation

Monitor blood sugar closely and adjust medication as needed with clinician guidance.

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 3 · Meta-analysis: Dietary Fiber Intake and Risk of Type 2 Diabetes 6 · Examine.com – Dietary Fiber

Fiber may affect absorption of certain antiepileptic drugs.

drug · Seizure medications

SeparateLimitedSeparate by 1–2h

Why

Fiber can bind drugs in the digestive tract and reduce their bioavailability.

recommendation

Take medications 1–2 hours before or after fiber supplements; consult prescriber for advice.

6 · Examine.com – Dietary Fiber

mechanisms of action

Brief explanations of how it works

Increases stool bulk and water content

Insoluble fiber passes through the GI tract largely intact, adding bulk to stool and accelerating gut transit.

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 2 · Systematic Review: Dietary Fiber and Constipation 7 · Harvard T.H. Chan School of Public Health – Fiber

Binds cholesterol and bile acids

Soluble fiber forms gels in the gut that trap cholesterol and bile acids, enhancing their excretion.

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 5 · EFSA Panel on Dietetic Products – Scientific Opinion on Dietary Reference Values for Carbohydrates and Fiber

Slows glucose absorption

Gel-forming fibers slow the digestion and absorption of carbohydrates, which improves blood sugar control.

1 · NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet 3 · Meta-analysis: Dietary Fiber Intake and Risk of Type 2 Diabetes

Sources & References

Primary literature and reviews on which these statements are based

7 sources

NIH Office of Dietary Supplements – Dietary Fiber Fact Sheet

Systematic Review: Dietary Fiber and Constipation

American Journal of Clinical Nutrition review on fiber and constipation.

Meta-analysis: Dietary Fiber Intake and Risk of Type 2 Diabetes

Diabetes Care meta-analysis on fiber and diabetes risk.

WebMD: Health Benefits of Fiber

EFSA Panel on Dietetic Products – Scientific Opinion on Dietary Reference Values for Carbohydrates and Fiber

European guideline on fiber intake and health.

Examine.com – Dietary Fiber

Evidence summary and user-focused recommendations.

Harvard T.H. Chan School of Public Health – Fiber

Public health resource summarizing fiber benefits and food sources.

Laatst bijgewerkt: 7 februari 2026

This information is for educational purposes only and does not replace medical advice.