Is there a list of foods that are safe with IBS?

Not one that applies to everyone. People with IBS react differently, and amount and context often matter. A dietitian can help you test foods safely.

Why is a food fine one day and not the next?

Portion size, what else you ate, stress, sleep, hormones and your bowel pattern that day can all change how your gut responds.

Should I cut this food out?

Not based on this tool alone. Cutting foods without guidance can make your diet unnecessarily restrictive. Speak to a doctor or dietitian first.

Free Thesos tool · Piece: Food

How Does This Food Seem to Work for You?

Explore whether a food shows a repeatable pattern for you—or whether the evidence is still mixed.

~2 min Your personal tolerance clue for one food

Your answers are not saved to your Thesos account unless you choose to save them. Educational, not a diagnosis.

About this tool, FAQ and sources

Explore your own experience with a food without reducing it to a universal “safe” or “unsafe” label. This tool looks at how often you've eaten it, what happened, when, and what else was going on.

How it works

You name a food and answer seven questions about how often you've eaten it, what usually happens, which symptoms, when, whether amount matters, whether outcomes change by day and what else is different on bad days. The result places your experience in one of three evidence states: not enough observations, inconsistent personal signal, or a repeatable self-reported pattern worth tracking.

It can

Show how consistent your own experience with a food is
Highlight portion and context clues worth tracking
Help you prepare for a conversation with a dietitian

It cannot

Diagnose IBS or any other condition
Tell you a food is safe or unsafe
Identify an allergy or intolerance
Replace dietitian-guided food testing

Questions

Is there a list of foods that are safe with IBS?: Not one that applies to everyone. People with IBS react differently, and amount and context often matter. A dietitian can help you test foods safely.
Why is a food fine one day and not the next?: Portion size, what else you ate, stress, sleep, hormones and your bowel pattern that day can all change how your gut responds.
Should I cut this food out?: Not based on this tool alone. Cutting foods without guidance can make your diet unnecessarily restrictive. Speak to a doctor or dietitian first.

Method and sources

Original Thesos evidence rule (v1.0) based only on your own reported observations. It uses no FODMAP data, serving thresholds or traffic-light ratings from any third party.

Eating, Diet & Nutrition for IBS · NIDDK
Irritable bowel syndrome (IBS) · NHS (UK)
Irritable bowel syndrome in adults (CG61) · NICE (UK)

Evidence sources last reviewed: 15 October 2026Last updated: 15 October 2026

For education and self-management only. Not a diagnosis. In an emergency, call your local emergency number.