Articles on: Interpreting your results

Antibiotics, Probiotics and Prebiotics

How do antibiotics impact the gut microbiome?

Antibiotics are used to treat bacterial infections by killing or inhibiting the growth of bacteria. While antibiotics can be crucial for treating infections, they can also have unintended effects on a person's gut microbiome, which is a complex community of trillions of microorganisms that live in the gastrointestinal tract. It can take weeks for your gut microbiome to build back up after a course of antibiotics.

How do antibiotics impact my FoodMarble breath test results?

If you've recently taken antibiotics, it's important to consider how the bacteria in your gut, those responsible for fermentation in your digestive tract, may have been impacted and therefore, to be aware that your day to day FoodMarble breath are likely to look different to before too. For some people, their results may appear erratic and difficult to interpret for a period of weeks after antibiotics.

Antibiotics & FoodMarble Challenges

After completing a course of antibiotics, the gut microbiome can usually recover over time. However, the extent and speed of recovery varies from person to person and depends on factors such as the type and duration of antibiotic treatment.

While you can continue to take regular day to day breath tests after antibiotics (if you're curious about your fermentation levels), please be mindful that we do not recommend starting the FoodMarble food intolerance tests until at least 4 weeks after you completed your course of antibiotics.

Probiotics and FoodMarble Results

Probiotics are live microorganisms (such as beneficial bacteria) that, when administered in adequate amounts, may provide health benefits. They are sometimes recommended during or after antibiotic treatment to help restore the balance of the gut microbiome. Probiotics can form a healthy part of your diet, and can alter your gut microbiome for the better, but it's important to understand that when you initially begin taking probiotics, your FoodMarble results may be elevated for a period of time. As you continue to take probiotics and build up certain species that are beneficial for your digestion, your results will be representative of your digestion.

Probiotics and FoodMarble Challenges

It is best to avoid taking probiotics during the fasting period and during the 3 hour testing window of your FoodMarble Challenge.


Unlike probiotics, which are live microorganisms (such as beneficial bacteria) themselves, prebiotics are substances that serve as a food source for these beneficial microbes. Prebiotics are substances that promote the growth of beneficial microorganisms in the gut. Including prebiotic-rich foods in your diet can support the recovery of the gut microbiome.

Food Sources of Prebiotics:

Chicory Root: Contains inulin, a well-known prebiotic.
Garlic and Onions: Rich in fructans, which are prebiotic fibers.
Asparagus: Contains inulin.
Jerusalem Artichokes: Contain inulin.

Prebiotics and FoodMarble Results

If you're eating prebiotic-rich foods, you're essentially feeding your good gut bacteria and it wouldn't be uncommon to experience high breath test results.

Updated on: 15/01/2024

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