Reboot Your Gut This Back-to-Routine Season

The term ‘gut health’ has continued to become an increasingly important aspect of overall health. Despite a recognition of gut function being integral to human health, questions previously remained on the difference to digestive health, whether gut health is modifiable, and how can it be measured. These questions were recently addressed via a consensus definition from the International Scientific Association for Probiotics and Prebiotics (ISAPP): "a state of normal gastrointestinal function without active gastrointestinal disease and gut-related symptoms that affect quality of life". The concept has importantly been expanded to recognise the role of the gut microbiome.

Within the past two decades, gut microbiome research has continued to expand, recognising the undeniable role in mediating health effects from diet and nutrient signalling to organ systems. Dysbiosis, known as a reduction in microbial diversity and absence of beneficial species, has been associated with cardiovascular disease, irritable bowel syndrome and a wide range of inflammatory responses.

So what does the evidence support for your gut this September? Not a juice cleanse but a handful of science-backed habits, applied consistently.

What the science says

Fibre is the single most consistent lever. 

Prioritising fibre‑rich, plant‑based foods supports beneficial bacteria and increases the production of short‑chain fatty acids such as butyrate, essential for maintaining intestinal barrier integrity and regulating inflammation. The UK Scientific Advisory Committee on Nutrition (SACN) recommends 30g of dietary fibre per day. Incorporate fibre-rich snacks such as mixed nuts, seeds, dried fruit, roasted chickpeas, or oat-based bars. Where possible, opt for whole grains including wholegrain wraps, oat pots, quinoa and seek out legume-based dishes and add a fibre supplement to your diet if you're falling short. 

Consider adding in a targeted probiotic to support. 

Probiotics are live microorganisms, often referred to as ‘good’ or ‘friendly’ bacteria, which have been shown to improve the gut microbiota and linked to numerous health benefits to the host. If needed, consult a professional for personalised guidance. Learn more about our FREE 1:1 consultations! 

Refined carbohydrates work against gut microbiota diversity. 

Diets high in refined sugar have been shown to shift the microbiota toward a more pro-inflammatory profile. Where possible, opt for foods that offer a richer source of dietary fibre along with beneficial micronutrients and polyphenols. 

Hydration is genuinely underrated. 

Lack of adequate hydration has been shown to disrupt gut microbial and immune function. Hydration strategies to help include carrying a refillable water bottle and aiming for 1.5–2 L/day. Where possible, choose herbal teas or sparkling water over sugary drinks.

Reboot trends to avoid

Extreme, rapid diet overhauls: the evidence above is built on sustained change over weeks, not days.

Unnecessary elimination diets:  cutting out entire food groups without clinical need may negatively impact the gut microbiome, which requires plant diversity, rich in polyphenols and different types of fibre. Dietary diversity, not restriction underpins a healthy gut.

"Detox" products: those which promise rapid transformation with limited scientific basis, often reducing fibre intake exactly where the evidence points the other way.

Conclusions

The latest International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition of gut health recognises it is not a finish line but something you sustain. Importantly, shaped by diet and consistent weekly habits, not what you attempt once. That's good news! No 30-day protocol required. Pick one evidence-backed habit, add more fibre diversity into your weekly routine, a carefully chosen probiotic, adequate hydration, regular movement, let it become automatic and then add the next.

Author: Charlotte, Co-Founder The Nutritional Biochemist

BSc Biochemistry, MSc Management, MSc Nutrition (KCL)

Sources:

·       Ehrenberg, D., & Cooper, C. (2025). Understanding the Mechanisms and the Impact of Food and Nutrition on Gut Health: A Narrative Review. Medical Research Archives, 13(4). doi:10.18103/mra.v13i4.6400

·       Hindle, V. K., Veasley, N. M., & Holscher, H. D. (2025). Microbiota-Focused Dietary Approaches to Support Health: A Systematic Review. The Journal of nutrition, 155(2), 381–401. https://doi.org/10.1016/j.tjnut.2024.10.043

·       Marco, M. L., Cunningham, M., Bischoff, S. C., Clarke, G., Delzenne, N., Lewis, J. D., Meisel, M., Merenstein, D., O'Toole, P. W., Staudacher, H. M., Szajewska, H., Wells, J. M., & Quigley, E. M. M. (2026). The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of gut health. Nature reviews. Gastroenterology & hepatology, 23(5), 432–448. https://doi.org/10.1038/s41575-026-01176-x

·       Martin-Gallausiaux C, Marinelli L, Blottière HM, Larraufie P, Lapaque N. SCFA: mechanisms and functional importance in the gut. Proceedings of the Nutrition Society. 2021;80(1):37-49. doi:10.1017/S0029665120006916

·       Ray, S., & Shankaran, P. (2026). Nutrition and the gut microbiome: a symbiotic dialogue influencing health and disease. Frontiers in nutrition, 13, 1761992. https://doi.org/10.3389/fnut.2026.1761992

·       Sanz, Y., Cryan, J. F., Deschasaux-Tanguy, M., Elinav, E., Lambrecht, R., & Veiga, P. (2025). The gut microbiome connects nutrition and human health. Nature reviews. Gastroenterology & hepatology, 22(8), 534–555. https://doi.org/10.1038/s41575-025-01077-5