The best format for a food and symptom diary is the one you can fill in close to the time, on most days, and read back later. No study has shown that paper, a notes app, a spreadsheet or a dedicated tracker gives people better answers about their own digestion. What research does show is that when and how reliably entries are made matters more than the medium.
This article compares the four options as ways of keeping a record. It is not a product recommendation, and a diary of any kind shows sequence rather than cause.
What the guidance says about format
Neither the NHS nor the British Dietetic Association names a preferred format. The NHS page on diet, lifestyle and medicines for IBS (last reviewed March 2025) suggests keeping a diary of what you eat and any symptoms, and the BDA’s IBS and diet fact sheet (January 2022, marked as under review) advises keeping a food and symptom diary while making changes. Neither specifies paper or digital.
So the choice is yours, and it is a practical one: which option will you actually keep up?
What research suggests about paper and electronic diaries
Most of the formal evidence comes from clinical research, not from people keeping a personal food diary, so it needs careful reading.
Timing of entries. In a study of 80 people with chronic pain, published in 2003 in Controlled Clinical Trials, participants were asked to make three entries a day at set times for 21 days. Those given a paper diary fitted with a sensor handed in cards that matched 90% of the assigned times, but electronic records showed that only 11% of entries had actually been made at the right time. On 32% of study days the paper binder was never opened, yet reported compliance on those days exceeded 90%. The group using an electronic diary with compliance-enhancing features, including time-stamped entries, had an actual compliance rate of 94%.
That is one study, in people with chronic pain, with fixed times and a research protocol. It does not show that anyone using a notebook is being unreliable. It does show that filling in a paper record later, from memory, can look the same on the page as an entry made at the time. If you do catch up on entries afterwards, mark them as added later, so a reader of the diary (including you) knows how much weight to give them.
Memory of symptoms. A study of 273 people with Rome III-diagnosed irritable bowel syndrome (mean age 39, 89% women) had them rate symptoms at the end of each day for a week using an electronic diary, then recall the week on day eight. Some details were recalled reasonably well at group level, such as worst pain, urgency and stool frequency. Others, such as typical pain, were vulnerable to recall bias, and some individuals struggled even with the details most people recalled well. The authors concluded that retrospective reports can distort the picture. This supports recording symptoms near the time they happen, in whichever format makes that easiest.
Does the medium change what people report? A systematic review and meta-analysis of 72 equivalence studies (Muehlhausen and colleagues, 2015) found that health questionnaires completed on paper and on electronic devices gave closely agreeing results overall (pooled correlation 0.88), although the individual correlations varied widely. That review concerns questionnaires, not food diaries, and it measures agreement of answers, not whether people keep going. It gives no reason to think a number you write on paper means something different from the same number tapped into a screen.
Taken together, these studies suggest that the format is less important than recording near the time, being honest about gaps, and using the same scale each day. None of them tested food-and-symptom diaries kept for personal use.
Comparing the four options
These are practical trade-offs, not research findings.
Paper notebook or printed sheet
- Needs no battery, signal or account, and allows free-text notes and sketches.
- Easy to hand to a clinician as it is, but harder to sort or count across weeks.
- Easy to leave at home when you eat out or travel, which can create gaps. See how missing check-ins change what a diary can show.
Notes app
- Always on your phone, quick to open, and can take free text and sometimes photos.
- Entries are only as consistent as the wording you choose each time, so write the same headings daily (for example time, food or drink, symptom).
- Comparing days means scrolling and re-reading rather than filtering.
Spreadsheet
- Fixed columns make it easier to keep the same fields every time and to sort or filter later.
- Typing into cells on a phone can be fiddly, so it often suits a quick end-of-day catch-up better than a meal-by-meal record.
- The free diary template opens in a spreadsheet and can also be printed.
Dedicated tracker app
- May offer reminders, time-stamped entries, fixed symptom fields and an export, but features differ by app, so check what a particular app does.
- Health data in an app is sensitive. Before relying on one, read what it collects and whether you can export and delete your records. An app’s privacy policy should say.
- A feature list does not make a pattern real. Be cautious of any app that presents a single food as a confirmed cause of symptoms.
Choosing for your situation
Think about the moments you are most likely to forget, then choose the format that is easiest at that moment.
- If you are most likely to forget at meals, pick whatever you can open in seconds. A one-line note on your phone beats a perfect spreadsheet you update on Sunday.
- If you mainly want something to show a professional, a tidy list or export is helpful, but only if the entries are accurate. Summarising a diary for a GP appointment can be done from any of these formats.
- If photos are easier than typing, a photograph can prompt memory, but it cannot show portion, ingredients or symptoms precisely. See whether meal photographs make a diary easier.
- If you want to try one format for a week, that is reasonable. Keep the same fields so any switch does not change what you are comparing, and note the day you changed.
- If you are unsure what to include, start from what to record in a food and symptom diary and keep the fields few.
You can also mix formats, such as quick phone notes during the day and a tidy copy in a spreadsheet later. If you do, mark which entries were made at the time and which were added afterwards.
Where GutBloom fits
GutBloom is an Android app that treats meals and symptom check-ins as equal parts of one daily record, with AI-assisted meal capture that you confirm or correct, and patterns shown with their uncertainty rather than as verdicts. Its approach to health data is set out in the privacy policy. If that approach to recording suits you, you can get GutBloom on Google Play.
When to speak to a professional
A diary helps you describe symptoms more clearly; it does not diagnose anything. The BDA advises seeing a doctor for unintentional and unexplained weight loss, rectal bleeding, or a family history of bowel or ovarian cancer, and symptoms that persist or worsen deserve medical attention however well they are recorded. Do not remove foods on the strength of a diary alone; if you are considering restriction, discuss it with a doctor or dietitian. This article has not been professionally reviewed.
Sources
- NHS — Irritable bowel syndrome (IBS): diet, lifestyle and medicines (reviewed March 2025)
- British Dietetic Association — Irritable bowel syndrome and diet food fact sheet (January 2022)
- Stone, Shiffman, Schwartz, Broderick and Hufford — Patient compliance with paper and electronic diaries, Controlled Clinical Trials (2003)
- Lackner and colleagues — The accuracy of patient-reported measures for GI symptoms: a comparison of real time and retrospective reports, Neurogastroenterology and Motility (2014)
- Muehlhausen and colleagues — Equivalence of electronic and paper administration of patient-reported outcome measures: a systematic review and meta-analysis, Health and Quality of Life Outcomes (2015)