Breath testing: When & how often?

How to Get the Most from Your Breath Testing

As a general rule of thumb, it’s helpful to take a breath test first thing in the morning before eating. A pre-food reading provides a clear “baseline” to compare against later in the day. If you notice a high reading before breakfast, it may suggest that fermentation from the previous day’s meals is still taking place in your gut.

To build a more complete picture, we recommend testing at regular intervals after meals—for example, 1 hour, 2 hours, and 3 hours post-meal. This helps you track how your digestion changes over time and identify when symptoms are most likely to appear.

We recommend a maximum of 10 breath tests in any 24-hour period. Spacing your tests out thoughtfully ensures that your FoodMarble device lasts longer while always giving you useful insights. You will be alerted in the app if you attempt to take breath tests within overly close succession.

Remember that any breath tests recorded are better than none. Don’t worry if you miss the “perfect” timing for a test and just take your next test as soon as you remember!

Making It Easier with Reminders

To help you stay consistent, the FoodMarble app includes automatic breath test reminders. As soon as you log a meal, you’ll get a Recent Meal reminder about an hour later. You can also set hourly reminders if you’d like more structure, so you never have to remember on your own.

Key Takeaways

• Take a baseline breath test first thing in the morning to compare against later readings.
• Test hourly after meals to spot early rises in fermentation levels that may link to specific foods.
• Keep to a maximum of 10 tests in 24 hours, except on Challenge days.
• Don’t stress about timing—each reading contributes to your dataset and can reveal useful patterns over time.
• Use app reminders to make testing consistent and effortless.

Updated on: 17/08/2025