Quick answer: A symptom diary is a dated, timed record of what you feel and what might be related, such as meals, bowel movements, medicines, sleep and stress. To make one your doctor will use, log at the moment symptoms happen, use the same scales every time (0–10 severity, Bristol stool type), keep it for 2–4 weeks, and bring a one-page summary rather than the raw pages.
Doctors ask questions your memory can't answer well: how many days last month, how long after eating, better or worse after a bowel movement. A symptom diary answers them with data.
But many diaries never get read. They're too long, too vague, or full of inconsistent ratings. This guide shows how to keep a diary that's quick to log and easy for a clinician to scan, with a filled example week focused on digestive symptoms.
Key takeaways
- Recalled symptoms often disagree with diaries. In one study, recall matched a one-week diary on stool consistency only 12.5% of the time [2].
- Log in the moment, or at least the same day. End-of-day entries are better than weekly recall, but still not free of recall bias [3].
- Use fixed scales (0–10 for severity, Bristol types 1–7 for stool [5]) so entries can be compared across days.
- Two to four weeks is usually enough to show a pattern for a visit. Some diagnoses rely on symptoms over months [4].
- Hand over a one-page summary, with the full diary as backup.
What is a symptom diary, and why does it help?
A symptom diary is a structured log of your symptoms over time, recorded as they happen, along with things that might affect them. For digestive problems that usually means meals, bowel movements, medicines, sleep, stress and your menstrual cycle.
It helps because memory is a poor instrument for symptoms. In a Swedish study of more than 700 people, agreement between recall questionnaires and prospective stool and symptom diaries was "generally poor". It was best for simple questions such as whether abdominal pain happened at all, and worst for complex ones such as whether pain was relieved by a bowel movement [1]. That's a problem, because "pain related to defecation" is part of how IBS is defined [4]. In another study of 100 patients with fecal incontinence, recalled bowel movement counts matched a one-week diary for only 30% of patients, and stool consistency for 12.5% [2].
A diary also makes timing visible. "Bloated after lunch most weekdays" and "bloated whenever I have lentils" point to different explanations, and only a timed record can tell them apart.
What should you record in a symptom diary for your doctor?
Record the symptom, its timing and severity, and the few things most likely to be connected. More fields isn't better. Consistency matters more than detail.
The doctor-ready schema
| Field | How to record it | Why it helps |
|---|---|---|
| Date & time | Exact time the symptom started | Shows timing relative to meals, sleep, medicines |
| Symptom | One word each: pain, bloating, nausea, urgency, reflux… | Easy to count |
| Severity | 0–10, same scale every time | Comparable across days |
| Duration | Minutes or hours | Separates brief cramps from all-day pain |
| Location & character (pain) | "Lower left, crampy, comes in waves" [6] | Location and type narrow the causes |
| What helped / worsened | "Better after BM", "worse lying down" | Key diagnostic clue [6] |
| Bowel movements | Time, Bristol type 1–7 [5], urgency, straining, blood, mucus | Frequency and form changes |
| Food & drink | Time + main ingredients (photo works) | Possible triggers and timing |
| Medicines & supplements | Name, dose, time | Side effects or effects on symptoms |
| Context | Sleep, stress, exercise, period, travel, illness | Non-food factors |
| Red flags | Blood, black stool, night waking, fever, vomiting | Must be visible at a glance |
For pain specifically, see our guide on how to describe abdominal pain, which breaks down location, character and timing.
If you want a blank printable version focused on food and symptoms, use on-page food and symptom diary example.
How often and for how long should you log?
Log symptoms when they happen, and do a quick end-of-day check for anything you missed. Keep going for 2–4 weeks before an appointment.
Why in the moment? Research on GI symptom reporting notes that even end-of-day diaries carry some recall bias because they look back over the day. Very frequent prompts (the "experience sampling" method) capture variability better but are harder to keep up [3]. The same research notes that paper diaries are prone to backfilling, where people fill in entries later [3]. For most people, a quick log at the time plus an evening check is a good balance.
Why 2–4 weeks? It's long enough to cover good and bad days, weekdays and weekends, and for many people a menstrual cycle. Some diagnoses are based on longer windows. Rome IV criteria for IBS, for example, look at symptoms over the last three months, starting at least six months before diagnosis [4]. If your appointment is further out, keep logging.
Make it sustainable:
- Log with as few taps or words as possible. Abbreviations are fine if you're consistent.
- Take a photo of meals instead of describing them.
- Set one evening reminder to catch gaps.
- Log good days too. "No symptoms" is data.
What does a good symptom diary look like?
A good entry is specific, timed and uses the same scales every time. Compare:
| Vague entry | Doctor-ready entry |
|---|---|
| "Stomach bad today" | "13:30 cramping pain 6/10, lower left, 40 min, eased after BM" |
| "Diarrhea again" | "07:10, 09:45, 14:20 BMs: Bristol 6, 7, 6; urgent ×2; no blood" |
| "Ate badly" | "12:45 burrito (beans, onion, cheese, salsa), large; cola" |
| "Bad night" | "Woke 03:00 with pain 5/10, had BM type 6" |
Illustrative week (example data, not a real patient):
| Day | Bowel movements (time: Bristol) | Symptoms (time, 0–10) | Meals worth noting | Context / flags |
|---|---|---|---|---|
| Mon | 07:30: 4 | — | Usual | Slept 7 h |
| Tue | 07:40: 5; 15:10: 6 (urgent) | Cramps 13:50, 5/10, 30 min | Lunch: lentil curry, naan | Work deadline |
| Wed | 08:00: 4 | Bloating 16:00, 3/10 | — | — |
| Thu | 07:20: 6; 13:30: 6 | Cramps 12:40, 6/10, relieved by BM | Lunch: bean burrito | Poor sleep (5 h) |
| Fri | 07:45: 4 | — | — | — |
| Sat | 09:30: 4 | — | Restaurant dinner | Period day 1 |
| Sun | 10:00: 5 | Bloating 20:00, 4/10 | — | — |
What a clinician might take from this week: symptoms cluster around midday on workdays, with pain relieved by a bowel movement, and there are no red flags. Possible threads to discuss are legume-heavy lunches, stress and sleep. That's a possible pattern to raise, not a conclusion. Our guide to spotting real patterns in your food and symptom log explains how to tell coincidence from a pattern worth testing.
How do you turn it into something your doctor will read?
Summarize. A clinician in a short appointment needs the headline numbers, the red flags and your questions, not every entry. AHRQ recommends writing down your questions and putting the most important first [7].
Your one-page summary should include:
- Date range covered, and when symptoms started
- Days with each main symptom (for example, "cramps on 9 of 28 days")
- Typical bowel frequency and Bristol types
- Timing patterns (after meals? night-time?)
- Red flags: present or absent
- What you've tried and what happened
- Your top three questions
Our guide to sharing your log with your doctor has a fill-in template and format tips.
How to track this with an app
Paper works if you'll use it. Apps make in-the-moment logging faster and do the counting for you.
If you use an app, inspect the actual record you plan to share and ask your practice which format it accepts. The Get Regular App tour and Doctor Report explanation describe the intended workflow; check current availability and the file itself before relying on it for a visit.
When to see a doctor rather than keep logging
A diary is for building a picture over weeks. Stop logging and contact a doctor promptly if you notice:
- Blood in your stool, or black, tarry stools
- Weight loss you can't explain
- Symptoms that wake you from sleep
- Fever, persistent vomiting, or severe or constant abdominal pain
- Signs of anemia, such as unusual tiredness or breathlessness
- A new, persistent change in bowel habits, especially later in life or with a family history of colorectal cancer, IBD or celiac disease
FAQ
What is the best way to keep a symptom diary? Use one consistent place, log at the time or the same day, use fixed scales (0–10 severity, Bristol 1–7 for stool), and keep entries short. Pick a format you'll still be using in week three: paper, a notes app or a dedicated tracker.
How long should I keep a symptom diary before seeing a doctor? Two to four weeks is usually enough to show patterns for a first appointment. Keep going if your visit is later or your symptoms come and go over longer cycles.
Should I write down symptoms every day even if I feel fine? Yes. Symptom-free days are part of the pattern. A quick "no symptoms" entry shows how often you're well, which matters as much as how often you're not.
Do doctors actually read symptom diaries? Many will, if it's easy to scan. That's why a one-page summary on top of your diary works better than pages of raw notes.
Sources
- Jones MP, et al. Gastrointestinal recall questionnaires compare poorly with prospective patient diaries for gastrointestinal symptoms: data from population and primary health centre samples. Eur J Gastroenterol Hepatol 2019. https://pubmed.ncbi.nlm.nih.gov/30394943/
- Hudgi A, et al. Accuracy of patient-reported bowel symptoms for fecal incontinence: Historical recall versus prospective evaluation. Neurogastroenterol Motil 2024. https://pmc.ncbi.nlm.nih.gov/articles/PMC10842103/
- Beckers AB, et al. Digital Instruments for Reporting of Gastrointestinal Symptoms in Clinical Trials: Comparison of End-of-Day Diaries Versus the Experience Sampling Method. JMIR Form Res 2021. https://pmc.ncbi.nlm.nih.gov/articles/PMC8663435/
- Rome Foundation. Rome IV Criteria. https://theromefoundation.org/rome-iv/rome-iv-criteria/
- Lewis SJ, Heaton KW. Stool form scale as a useful guide to intestinal transit time. Scand J Gastroenterol 1997. https://pubmed.ncbi.nlm.nih.gov/9299672/
- MedlinePlus. Abdominal pain. https://medlineplus.gov/ency/article/003120.htm
- AHRQ. Be More Engaged in Your Healthcare: Tips for Patients. https://www.ahrq.gov/patients-consumers/patient-involvement/ask-your-doctor/questions-before-appointment.html
This article is for general education and isn't medical advice. Get Regular is a tracking app — it doesn't diagnose or treat any condition. If you have red-flag symptoms or ongoing changes in your digestion, talk to a doctor.