GLP-1 Fibre Intake Calculator
Calculate your daily fibre goal with food examples
This calculator estimates your daily fibre goal using established nutrition guidelines and shows high-fibre foods to help you reach your target — useful for supporting bowel regularity while on GLP-1 medications.
Fibre Intake Calculator
How to Use This Calculator
Enter your age and sex
We use guideline-based fibre targets that vary by age and sex.
Get your fibre goal + food examples
You'll see your daily fibre target and a list of high-fibre foods to help you reach it.
Frequently Asked Questions
Answers about fibre intake, GLP-1 constipation, and how to increase fibre safely.
What is the GLP-1 Fibre Intake Calculator?
It estimates a daily fibre goal using established nutrition guidelines and shows high-fibre foods to help you reach your target. The calculator uses age and sex to determine your target based on National Academy of Medicine recommendations.
Why does fibre matter when I'm on GLP-1 medication?
Constipation can happen on GLP-1 therapy, and expert consensus recommends increasing water and fibre intake and mobility to help. Adequate fibre supports bowel regularity and may help manage GI side effects.
How much fibre do I need per day?
Common guideline targets (National Academy of Medicine) are 25 g/day for women ≤50 and 38 g/day for men ≤50, with slightly lower targets after age 50 (21 g/day for women, 30 g/day for men).
Soluble vs insoluble fibre: what's the difference?
Soluble fibre dissolves in water and forms a gel, which can help stool consistency. Insoluble fibre adds bulk and helps move things through. Both can help with regularity, but tolerance varies — increase gradually regardless of type.
Should I increase fibre quickly to fix constipation?
Usually no — increasing too fast can cause wind, bloating, and cramping. Add fibre gradually (about 3 g every 3–4 days) and drink fluids to help fibre work properly. If constipation is severe, talk to your clinician.
Do fibre supplements count?
Yes, fibre supplements can help some people. GI guidelines support fibre supplementation for chronic constipation, and some evidence highlights psyllium as a helpful option. Talk to a clinician or pharmacist if you're unsure which supplement is right for you.
What foods are high in fibre?
Good sources of fibre include:
- Beans and legumes (lentils, chickpeas, black beans)
- Whole grains (oats, quinoa, whole wheat bread)
- Vegetables (broccoli, carrots, Brussels sprouts)
- Fruits (apples, pears, berries, oranges)
- Nuts and seeds (almonds, chia seeds, flaxseed)
Start with foods you tolerate well and increase portions gradually.
Data Sources
This calculator uses evidence-based recommendations from the following sources:
- Mayo Clinic — Dietary fiber: Essential for a healthy diet — age/sex fibre targets (25/21 women; 38/30 men)
- Academy of Nutrition and Dietetics — Position paper on dietary fibre — Adequate Intake concept: 14 g/1,000 kcal; 25 g women; 38 g men
- Mayo Clinic — High-fiber foods — guidance to increase fibre gradually and drink fluids
- GLP-1 GI Adverse Events Expert Consensus (2022) — Constipation guidance: increase water, fibre, and mobility; water reduction can contribute
- ACG/AGA Constipation Guideline — Supports fibre supplementation in chronic idiopathic constipation
- PMC Fiber Supplements Review — Notes psyllium can increase stool water and improve constipation symptoms
- USDA FoodData Central — Fibre content per serving for common foods
⚠️ Important Medical Disclaimer
This calculator is for informational purposes only and does not constitute medical advice. Always consult with your healthcare professional before making any changes to your medication dosing.
Dosage calculations should be verified by a healthcare professional. Glapp and its contributors assume no liability for medication dosing errors or adverse events.
Off-Label Use Notice: Split dosing features represent off-label use not approved by the FDA. Discuss with your prescriber before implementing.