The idea of "resetting" your gut has become popular - after antibiotics, illness, poor eating, or just feeling sluggish. But what does this actually mean, and how realistic is it?
The good news: your gut microbiome is remarkably adaptable. Changes in diet can shift your bacterial populations within days. The reality check: you can't completely rebuild your microbiome from scratch, and dramatic "gut cleanses" often do more harm than good.
What We Mean By "Reset"
A gut reset isn't about wiping clean and starting over. It's about shifting the balance of your gut bacteria toward a more diverse, beneficial profile. This happens through:
Feeding beneficial bacteria - Giving them the fibre and nutrients they thrive on.
Starving problematic bacteria - Reducing sugars and processed foods that feed inflammatory strains.
Adding new strains - Through fermented foods or specific dietary changes.
Allowing recovery - Time without irritants for gut lining repair.
When a Gut Reset Makes Sense
You might benefit from a focused gut-support period if you've experienced:
- Recent antibiotic treatment
- A bout of food poisoning or gastroenteritis
- Prolonged stress affecting digestion
- Extended period of poor eating (travel, illness, busy period)
- Persistent bloating, irregular bowels, or digestive discomfort
It's not a cure for diagnosed conditions like IBS, IBD, or SIBO - those require proper medical management.
A Three-Phase Approach
Phase 1: Remove (Days 1-7)
Reduce the load on your digestive system and remove potential irritants.
- Eliminate alcohol completely
- Cut out ultra-processed foods
- Reduce added sugars significantly
- Minimise artificial sweeteners
- Consider reducing common irritants: gluten, dairy, if you suspect sensitivity
- Avoid very fatty or fried foods
Phase 2: Repair (Days 8-14)
Support gut lining healing and beneficial bacterial growth.
- Emphasise prebiotic foods: garlic, onions, leeks, asparagus
- Include bone broth or collagen-rich foods
- Add omega-3 sources: oily fish twice this week
- Include glutamine-rich foods: chicken, fish, eggs
- Plenty of colourful vegetables
- Stay well hydrated
Phase 3: Repopulate (Days 15-21+)
Introduce beneficial bacteria and diverse fibres.
- Daily fermented foods: yoghurt, kefir, sauerkraut, kimchi
- Increase fibre variety: aim for 30 plant foods weekly
- Include resistant starch: cooled potatoes, green bananas
- Consider a probiotic supplement if recovering from antibiotics
- Gradually reintroduce foods, noting any reactions
Foods for Each Phase
Emphasise Throughout
- Vegetables (all types, especially greens)
- Lean proteins (fish, chicken, eggs)
- Whole grains (oats, rice, quinoa)
- Legumes (if tolerated)
- Nuts and seeds
- Olive oil
- Fresh fruits (especially berries)
- Herbs and spices
Reduce or Avoid
- Alcohol
- Ultra-processed foods
- Sugary drinks
- Excessive caffeine
- Artificial sweeteners
- Fried foods
- Processed meats
- Refined carbohydrates
Beyond Diet: Supporting Factors
Your gut microbiome responds to more than just food:
- Sleep - Poor sleep disrupts gut bacteria. Prioritise 7-9 hours during your reset.
- Stress management - Chronic stress alters gut function and bacterial balance. Include relaxation practices.
- Movement - Regular physical activity supports microbiome diversity. Daily walks count.
- Time outdoors - Exposure to diverse environmental microbes supports gut diversity.
- Antibiotics - Only when medically necessary. If prescribed, ask about probiotic support.
When to Seek Help
A dietary reset is not appropriate for: unexplained weight loss, blood in stool, severe or worsening symptoms, symptoms that don't improve after 2-3 weeks, or suspected food allergies (as opposed to intolerances). See your GP for proper investigation.
Realistic Expectations
What you might notice:
- Week 1: Possible temporary increased bloating (gut adjusting), improved energy, better sleep
- Week 2: Reduced bloating, more regular bowel movements, clearer thinking
- Week 3+: Established new patterns, improved tolerance of prebiotic foods, stable digestion
What you won't achieve: complete microbiome overhaul, cure of chronic conditions, or permanent transformation from a three-week protocol. Real gut health is an ongoing commitment to eating and living well.
After the Reset
The point isn't to return to previous habits. Use the reset to:
- Identify patterns - What foods cause issues when reintroduced?
- Establish habits - Which new foods or practices will you maintain?
- Build variety - Continue aiming for 30+ plant foods weekly
- Include fermented foods regularly - Not just during resets
- Maintain the lifestyle factors - Sleep, stress management, movement
The Bottom Line
A gut "reset" is really about giving your digestive system a break from irritants while feeding beneficial bacteria. The three-phase approach - remove, repair, repopulate - provides a sensible structure. But the real work is what comes after: maintaining fibre diversity, including fermented foods regularly, managing stress, sleeping well, and keeping processed foods minimal. Your microbiome adapts continuously to how you live and eat.
References
- David, L.A., et al. (2014). Diet rapidly and reproducibly alters the human gut microbiome. Nature, 505(7484), 559-563. doi:10.1038/nature12820
- McDonald, D., et al. (2018). American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems, 3(3). doi:10.1128/mSystems.00031-18
- British Dietetic Association. (2024). Gut Health Food Fact Sheet. bda.uk.com
