Trying to remember what you ate before you felt bloated or uncomfortable? A food and symptom diary gives you one place to record meals, drinks and how you felt—without relying on memory.
You can use a notebook, a note on your phone or the template below. If filling in a table feels like another chore, you can also ask free ChatGPT to organise your everyday notes for you. A short message about lunch can become a diary entry you check and keep.
This guide gives you both options: a simple table and ready-to-copy prompts for an AI-assisted diary. The aim is to make recording easier and give you a clearer account of what happened.
What should you record?
Keep entries short enough that you will actually use the diary. Include:
- When you ate or drank: an approximate time is fine.
- What you had: include drinks, sauces, snacks and ingredients you know.
- Rough amount: use everyday descriptions such as a mug, bowl or two slices.
- How you felt and when: write your own description, including when it started and roughly how long it lasted.
- Other useful context: for example, an unusually rushed meal or a change to your normal routine. Record it as context, not an explanation.
Record times when you felt fine too. A diary containing only uncomfortable moments leaves out part of your day.
Copy this food and symptom diary template
| Date and time | Food and drink, including ingredients | Approximate amount | Symptoms, start time and duration—or “none noticed” | Other notes |
|---|---|---|---|---|
Copy the table into a document, or use the column headings as prompts in a notebook. If your GP or dietitian has supplied a diary, follow their format and instructions.
A worked example
This is an invented example of a diary entry, not evidence of a link between these foods and symptoms:
| Date and time | Food and drink | Approximate amount | Symptoms | Other notes |
|---|---|---|---|---|
| Monday, 12:30 | Sandwich with bread, cheese and tomato; water | One sandwich; one glass | Bloating noticed at 14:00; lasted about an hour | Ate while travelling; sauce ingredients unknown |
“Sauce ingredients unknown” is a useful note. You do not need to guess or reconstruct every ingredient for the record to be worth keeping.
How to use free ChatGPT for your food diary
You do not need a paid subscription to try this text-based workflow. Free ChatGPT also supports image and file uploads, with separate tool limits. OpenAI’s free-plan guide
1. Set up your diary with one prompt
Open ChatGPT, sign in to a free account and start a chat for your diary. Copy this prompt:
Help me keep a food and symptom diary. Turn the notes I give you into a table with these columns: date and time; food and drink, including known ingredients; approximate amount; symptoms with start time and duration; other notes. Use only details I provide. Mark missing information as “not recorded”—never treat a missing symptom note as “no symptoms”. Ask me to clarify anything ambiguous. Keep symptom timings separate from meal timings. Do not diagnose, identify trigger foods or recommend excluding foods. After each entry, show me the new or changed rows to check.
2. Add a quick note when it suits you
You can type naturally. For example, this invented entry gives enough detail to organise:
14 September 2026: at 12:30 I had one cheese and tomato sandwich and a glass of water. I don’t know the sauce ingredients. Bloating started at 14:00 and lasted about an hour. I ate while travelling. Please add this to my diary.
Use an actual date and time, rather than just “yesterday”. You can add symptoms later by saying which date and entry you want to update. If you felt fine, record that explicitly too.
Prefer talking? Free ChatGPT has limited voice access; available options and allowances can change. Speak your note, then check the written dates, foods and amounts before keeping it. OpenAI’s voice guide
If you upload a clear photo of a food label, try: “Copy the readable ingredients into my note and flag any text you cannot read.” Check the result against the packaging. A meal photo alone cannot reliably tell you hidden ingredients or exact portions, so add what you know yourself.
3. Check the entry and keep your own copy
Read each new row before accepting it. If something is wrong, give the correction explicitly: “Change the drink to water; I did not have coffee.” Ask to see the corrected row.
At the end of the day, ask:
Show all entries for 14 September 2026 in a table I can copy into my own document. Keep missing details marked “not recorded”. Do not add anything that was not in my notes.
Check it against your original messages and save it in your own document or spreadsheet. Treat that checked copy as your main diary. Do not rely on ChatGPT remembering every entry indefinitely; if you start a new chat, paste in the relevant record again. If you reach a tool limit, keep recording in your own notes.
4. Turn your checked diary into an appointment summary
Once you have several days of entries, paste in your checked table and try:
Summarise only the diary entries below for an appointment. State the dates covered, list the symptoms I recorded with their dates and times, and identify gaps in the record. Separate my observations from anything uncertain. Suggest three questions I could ask my GP or dietitian. Do not infer which food caused a symptom, diagnose a condition or recommend an exclusion diet.
Compare the summary with your diary and take both to the appointment. A useful summary helps you explain your experience; an AI-generated association does not establish a food intolerance or allergy.
A quick privacy check before you start
Share only details you are comfortable putting into an online service; leave out names, addresses and identifying documents. In ChatGPT, you can turn off “Improve the model for everyone” under Settings → Data Controls; chats can remain in your history without being used for model training. Temporary Chat does not save conversations in your history, so it is less convenient for an ongoing diary unless you keep a separate copy. OpenAI’s data controls guide
Make the diary easy to maintain
Write an entry soon after eating when practical. If a meal has several ingredients, a photo of the packaging or menu can help you fill in details later. Keep the original description rather than changing it to fit a theory about a particular food.
When you look back, note questions rather than conclusions: “Did this happen on other days?” or “What else was in that meal?” One entry cannot tell you whether an ingredient was responsible.
What should you do with the record?
If symptoms keep returning, speak to your GP and take your notes. The NHS includes keeping a food and symptom diary among possible steps when investigating food intolerance. Seek professional advice before significant or prolonged dietary restriction. NHS food intolerance guidance
Exploring hair sensitivity testing
If you are exploring at-home options, TMFS offers an At-home Hair Sensitivity Test to help you discover potential food and environmental sensitivities. It uses bioresonance to assess energetic frequencies from a hair sample and provides personalised results showing potential sensitivity patterns. It does not test for or diagnose food allergy or intolerance, or prove what caused your symptoms.
