Get your gut acidity right

by Ashleigh Feltham,  Accredited Practising Dietitian and Accredited Nutritionist

Your gut plays many important roles in keeping you alive, healthy and nourished, and it’s essential to remove waste products. You may not think this system needs microbes to maintain its health, but you’d be wrong. Your gut microbiome is a conductor of many functions that dictate the overall health and workings of your gut.

To achieve and maintain a healthy gut microbiome, which is made up of a diverse variety of health-promoting microbes, you need to feed these microbes. It is just like having a pet living in your body; if you do not feed it, it will die, only to have a less healthy variety take its place, or an imbalance of the different types of microbes occurs, which leads to ill health.


When health-promoting microbes feed on prebiotics, they produce signals called short chain fatty acids (SCFA). Three common varieties of healthy SCFAs include lactic acid, butyric acid and propionic acid. SCFA affect the health and function of almost every organ in the body, including the gut. One important role SCFAs play is influencing the pH, or level of acidity, in different parts of the gut.

Different sections of your gut require different levels of acidity to maintain normal function. For example, the acidity level of your stomach is much higher than is healthy for your colon, which requires a lower level of acidity for normal function. One role of the SCFAs is to decrease the pH of the colon. This is important to help the colon function and prevent disease states within the colon.

Take a lifestyle approach. Keep your gut and microbiome healthy by including a diverse range of plant foods each day. This includes nuts, seeds, wholegrains, bean and legumes, fruit and vegetables. Aiming for 30 different plant foods each week is a good goal to provide health-promoting microbes with the specific prebiotic fuel they require to stay healthy and alive. An adult requires 25-38g of dietary fibre each day for good health.

Different varieties of microbes require different prebiotic fibre to function and send out different types of SCFA, promoting good health of the body including the gut.

gut health and estrogen balance

Take home message:

Good gut health is the key to overall health and longevity. Make sure you are feeding your gut microbiome the fuel it requires to assist you to live a life of vitality and wellness.



  1. Hernot D.C., Boileau T.W., Bauer L.L., Middelbos I.S., Murphy M.R., Swanson K.S., Fahey Jr G.C. In vitro fermentation profiles, gas production rates, and microbiota modulation as affected by certain fructans, galactooligosaccharides, and polydextrose. J. Agric. Food Chem. 2009;57:1354–1361. doi: 10.1021/jf802484j. [PubMed] [CrossRef] [Google Scholar]
  2. Zhou Z., Zhang Y., Zheng P., Chen X., Yang Y. Starch structure modulates metabolic activity and gut microbiota profile. Anaerobe. 2013;24:71–78. doi: 10.1016/j.anaerobe.2013.09.012. [PubMed] [CrossRef] [Google Scholar]
  3. Davani-Davari D, Negahdaripour M, Karimzadeh I, et al. Prebiotics: Definition, Types, Sources, Mechanisms, and Clinical Applications. Foods. 2019;8(3):92. Published 2019 Mar 9. doi:10.3390/foods8030092