Guide · Food and modes · 2 min read
Getting enough fiber
Fiber helps your digestion and helps prevent constipation. 1 Eating plenty of it is also linked to a lower risk of heart disease, stroke, type 2 diabetes and bowel cancer. 1
How much
UK guidelines say adults should aim for 30 g of fiber a day; most adults eat about 20 g. 1 It's best to get it from a variety of foods. 1
Go gradually
- In the first few days of a GLP-1 medicine, avoiding fatty or high-fiber foods can help with stomach side effects. 2
- After that, increase fiber from foods gradually, and drink enough fluids alongside it. 2
- If constipation continues despite changes to what you eat, fiber supplements may also help. 2
Where it comes from
- Breakfast: porridge oats or a plain wholewheat cereal. 1
- Bread, pasta and grains: wholemeal bread, wholewheat pasta, bulgur wheat or brown rice. 1
- Potatoes with their skins on, such as a baked potato. 1
- Pulses: add beans, lentils or chickpeas to stews, curries and salads. 1
- Vegetables with meals, as a side or in sauces and stews. 1
- Snacks: fresh fruit, vegetable sticks, oatcakes, or unsalted nuts and seeds. 1
Wholemeal spaghetti with a lentil and tomato sauce gives around 11 g of fiber. 1 On a food label, a high-fiber food has 6 g or more of fiber per 100 g. 1
If you use FODMAP mode
Many high FODMAP foods are also high in fiber, so getting enough can be harder on a low FODMAP diet. 3 Low FODMAP servings that add fiber: two thirds of a cup of firm tofu (6 g), a cup of cooked brown rice or quinoa (3 g), a medium orange (3 g), half an unpeeled potato (2 g) or a quarter cup of drained canned chickpeas (2 g). 3
In CalJab
Your fiber target and today's total are on Today. If you take a fiber supplement, add it in Health under Medicines; it's among the often added ones, and supplement reminders are in Reminders.
When to see a doctor
- Sudden changes in your bowel habits, blood in your poo, needing to go at night, or severe or ongoing diarrhea: talk to your doctor. 3
If you have a bowel condition, ask your doctor or dietitian how much fiber suits you.
Sources
- 1NHS: How to get more fibre into your diet. Last reviewed 2 March 2026. nhs.uk
- 2Mozaffarian D, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from ACLM, ASN, OMA and The Obesity Society. Obesity 2025;33(8):1475-1503. pmc.ncbi.nlm.nih.gov
- 3Monash University FODMAP: Getting enough fibre (J. Varney, 2021). monashfodmap.com
Written by the CalJab team, with sources. It does not replace your doctor's advice. Found a mistake? Write to support@caljab.app.