Understanding the results from your Methane Breath CH4ECK™ Test
Understanding the results from your Methane Breath CH4ECK™ Test

Understanding the results from your Methane Breath CH4ECK™ Test

By Sarah Bloor, Clinical GI Physiologist

Methane gas is produced by microorganisms called methanogens, which colonise the digestive tract in humans. The methane crosses into the blood and is carried to the lungs where it can be exhaled in breath. Breath methane is detected in around 30%-50% of the healthy adult population3.

However, elevated breath methane is associated with bloating, gas, and constipation-related diseases, such as constipation predominant irritable bowel syndrome (IBS-C) and functional constipation4. Methane gas slows intestinal transit time, which may contribute to the development of constipation5.

Research shows that higher levels of breath methane production correlates with greater severity of constipation6. Higher levels of breath methane are also associated with obesity and reduced weight loss following bariatric surgery7,8. Methanogens may influence the amount of calories your body absorbs by increasing the bacterial production of short-chain fatty acids (SCFAs) in the colon9.

The methanogen thought to predominantly overgrow in humans is a species of archaea called Methanobrevibacter smithii10. Since methanogens may overgrow in the small bowel or colon, we call this intestinal methanogen overgrowth11. This can be diagnosed by a Methane Breath CH4ECK™ test.

Cut-offs

  • Positive: ≥10 ppm
  • Inconclusive: 4-9 ppm
  • Negative: <4 ppm

What does a positive test mean?

Breath methane levels of ≥10 ppm are considered ‘methane-positive’1. This is indicative of intestinal methanogen overgrowth.

What should I do if my test is positive?

It may be useful to discuss your results with a healthcare practitioner who is familiar with the management of intestinal methanogen overgrowth, such as a gastroenterologist or registered dietitian. If you undergo treatment for methane, it is easy to repeat the Methane Breath CH4ECK regularly to see if your methane has been reduced/eradicated.

What does an inconclusive test mean?

Breath methane levels of ≥4 ppm at baseline are predictive of those who will be diagnosed as ‘methane positive’ on a complete lactulose breath test (i.e. produce breath methane levels of ≥10ppm)2. Therefore, methane values of 4-9 ppm are inconclusive.

What should I do if my test is inconclusive?

A follow up lactulose breath test is recommended to confirm a positive result for intestinal methanogen overgrowth. However, this would require a referral from a healthcare practitioner.

What does a negative test mean?

Breath methane levels of <4 ppm are not suggestive of intestinal methanogen overgrowth.

What should I do if my test is negative? While your test is negative, this does not exclude small intestinal bacterial overgrowth as a cause of your digestive symptoms. Therefore, a follow up lactulose breath test may be useful. However, this would require a referral from a healthcare practitioner.

Treatments

There is no gold standard treatment for excessive methane production. Below is a list of recommendations based on current research. However, please seek help from a qualified medical practitioner before starting any of these methods. Post treatment it may be beneficial to repeat the Methane Breath CH4ECK to see if your methane levels have reduced.

Antibiotics

Research suggests the most effective treatment for intestinal methanogen overgrowth is a combination of antibiotics called Rifaximin and Neomycin12. However, these are not readily available on the NHS and would require the guidance of a medical practitioner familiar with this treatment.

Elemental Diet

This is a liquid diet that aims to starve the bacteria in the lower part of the digestive tract. While there are no studies in the treatment of methane production, it is effective in reducing hydrogen, which is a fuel source for the methanogens13. However, this form of treatment should only be done under the care of a trained dietitian.

Low FODMAP diet

A low FODMAP diet may alleviate symptoms in patients with IBS-C14. FODMAPs (Fermentable Oligo-, Di-, Monosaccharides and Polyols) are short-chain carbohydrates found in fibrous plant foods and calorie-free foods. These are fermented by bacteria in the gut to produce hydrogen gas, which is then used to form methane by methanogens. A low FODMAP diet may improve symptoms, but studies have shown that a low FODMAP diet did not change the number of methanogens nor reduce breath methane levels15,16.

Prebiotics and Probiotics

A recent study found that probiotic use may predispose the gut to methanogen overgrowth17. However, the probiotic strain Lactobacillus reuteri (17938) was shown to reduce symptoms of chronic constipation and reduce levels of breath methane18. This can be found in the probiotic Bio Gaia Gastros. Since overgrowth of methanogens is a form of intestinal dysbiosis, or an imbalance in the gut microbiome, then promoting beneficial bacteria with prebiotics may help to restore balance in the gut. Many prebiotic foods are considered to be high FODMAP, so it may be useful to try a prebiotic supplement, such as Bimuno.

Current research

Our research at the Functional Gut Clinic has shown a link between oral iron supplements and increased breath methane production. If you are currently taking iron supplements, or are planning to do so, then please contact admin@thefunctionalgutclinic.com

DISCLAIMER

The information provided is for educational purposes only and should not be interpreted as diagnostic or as treatment recommendations. Please seek advice from a healthcare practitioner, such as a gastroenterologist or dietitian, if you require further information.

References

1. Rezaie, A., Buresi, M., Lembo, A., Lin, H., McCallum, R., Rao, S., Schmulson, M., Valdovinos, M., Zakko, S., Pimentel, M.: Hydrogen and

Methane-Based Breath Testing in Gastrointestinal Disorders: The North American Consensus. The American journal of

gastroenterology 112(5), 775-784 (2017). doi:10.1038/ajg.2017.46

2. Gottlieb, K., Le, C., Wacher, V., Sliman, J., Cruz, C., Porter, T., Carter, S.: Selection of a cut-off for high- and low-methane producers using a

spot-methane breath test: results from a large north American dataset of hydrogen, methane and carbon dioxide measurements in

breath. Gastroenterology report 5(3), 193-199 (2017). doi:10.1093/gastro/gow048

3. Konstantinos, T., lt, sup, gt, lt, sup, gt, Christopher, C., lt, sup, gt, lt, sup, gt, Mark, P., lt, sup, gt, *, lt, sup, gt: Methanogens, Methane and

Gastrointestinal Motility. J Neurogastroenterol Motil 20(1), 31-40 (2014). doi:10.5056/jnm.2014.20.1.31

4. Kunkel, D., Basseri, R.J., Makhani, M.D., Chong, K., Chang, C., Pimentel, M.: Methane on Breath Testing Is Associated with Constipation: A

Systematic Review and Meta-analysis. Digestive Diseases and Sciences 56(6), 1612-1618 (2011). doi:10.1007/s10620-011-1590-5

5. Pimentel, M., Lin, H.C., Enayati, P., van den Burg, B., Lee, H.-R., Chen, J.H., Park, S., Kong, Y., Conklin, J.: Methane, a gas produced by enteric

bacteria, slows intestinal transit and augments small intestinal contractile activity. American Journal of Physiology-Gastrointestinal

and Liver Physiology 290(6), G1089-G1095 (2006). doi:10.1152/ajpgi.00574.2004

6. Chatterjee, S., Park, S., Low, K., Kong, Y., Pimentel, M.: The Degree of Breath Methane Production in IBS Correlates With the Severity of

Constipation. Official journal of the American College of Gastroenterology | ACG 102(4) (2007).

7. Basseri, R.J., Basseri, B., Pimentel, M., Chong, K., Youdim, A., Low, K., Hwang, L., Soffer, E., Chang, C., Mathur, R.: Intestinal methane

production in obese individuals is associated with a higher body mass index. Gastroenterology & hepatology 8(1), 22-28 (2012).

8. Mathur, R., Mundi, M.S., Chua, K.S., Lorentz, P.A., Barlow, G.M., Lin, E., Burch, M., Youdim, A., Pimentel, M.: Intestinal methane production

is associated with decreased weight loss following bariatric surgery. Obesity Research & Clinical Practice 10(6), 728-733 (2016).

doi:https://doi.org/10.1016/j.orcp.2016.06.006

9. Turnbaugh, P.J., Ley, R.E., Mahowald, M.A., Magrini, V., Mardis, E.R., Gordon, J.I.: An obesity-associated gut microbiome with increased

capacity for energy harvest. Nature 444(7122), 1027-1031 (2006). doi:10.1038/nature05414

10. Kim, G., Deepinder, F., Morales, W., Hwang, L., Weitsman, S., Chang, C., Gunsalus, R., Pimentel, M.: Methanobrevibacter smithii is the

predominant methanogen in patients with constipation-predominant IBS and methane on breath. Dig Dis Sci 57(12), 3213-3218

(2012). doi:10.1007/s10620-012-2197-1

11. Pimentel, M., Saad, R.J., Long, M.D., Rao, S.S.C.: ACG Clinical Guideline: Small Intestinal Bacterial Overgrowth. Official journal of the

American College of Gastroenterology | ACG 115(2) (2020).

12. Pimentel, M., Chang, C., Chua, K.S., Mirocha, J., DiBaise, J., Rao, S., Amichai, M.: Antibiotic treatment of constipation-predominant irritable

bowel syndrome. Dig Dis Sci 59(6), 1278-1285 (2014). doi:10.1007/s10620-014-3157-8

13. Pimentel, M., Constantino, T., Kong, Y., Bajwa, M., Rezaei, A., Park, S.: A 14-day elemental diet is highly effective in normalizing the

lactulose breath test. Dig Dis Sci 49(1), 73-77 (2004). doi:10.1023/b:ddas.0000011605.43979.e1

14. Halmos, E.P., Power, V.A., Shepherd, S.J., Gibson, P.R., Muir, J.G.: A diet low in FODMAPs reduces symptoms of irritable bowel syndrome.

Gastroenterology 146(1), 67-75.e65 (2014). doi:10.1053/j.gastro.2013.09.046

15. Sloan, T.J., Jalanka, J., Major, G.A.D., Krishnasamy, S., Pritchard, S., Abdelrazig, S., Korpela, K., Singh, G., Mulvenna, C., Hoad, C.L., Marciani,

L., Barrett, D.A., Lomer, M.C.E., de Vos, W.M., Gowland, P.A., Spiller, R.C.: A low FODMAP diet is associated with changes in the

microbiota and reduction in breath hydrogen but not colonic volume in healthy subjects. PloS one 13(7), e0201410 (2018).

doi:10.1371/journal.pone.0201410

16. Ong, D.K., Mitchell, S.B., Barrett, J.S., Shepherd, S.J., Irving, P.M., Biesiekierski, J.R., Smith, S., Gibson, P.R., Muir, J.G.: Manipulation of

dietary short chain carbohydrates alters the pattern of gas production and genesis of symptoms in irritable bowel syndrome. Journal

of gastroenterology and hepatology 25(8), 1366-1373 (2010). doi:10.1111/j.1440-1746.2010.06370.x

17. Mitten, E., Goldin, A., Hanifi, J., Chan, W.W.: Recent Probiotic Use Is Independently Associated With Methane-Positive Breath Test for Small

Intestinal Bacterial Overgrowth: 1151. Official journal of the American College of Gastroenterology | ACG 113 (2018).

18. Ojetti, V., Petruzziello, C., Migneco, A., Gnarra, M., Gasbarrini, A., Franceschi, F.: Effect of Lactobacillus reuteri (DSM 17938) on methane

production in patients affected by functional constipation: a retrospective study. European review for medical and pharmacological

sciences 21(7), 1702-1708 (2017).

Do you have IBS-D? We need you!

We've got a number of exciting research trials to help change the future of IBS-D. Join us, we're shaping the future of IBS.