Have you recently finished a course of antibiotics only to find your digestion feels a little off balance? Perhaps you have noticed bloating, looser stools or a change in appetite. In my practice as a registered nutritionist, I often meet people who were relieved to clear an infection, then found their digestion unsettled for a while afterwards.
Antibiotics are important medicines that target harmful bacteria, but they do not discriminate. Alongside the bacteria causing the infection, they also reduce some of the beneficial bacteria living in your gut, which temporarily lowers microbial diversity. The encouraging news is that research suggests the microbiome often recovers over time, and everyday food choices may help support that process.
Why Antibiotics Can Affect Digestion
Your gut is home to trillions of micro-organisms that produce short-chain fatty acids, interact with your immune system and play a part in digestion. When antibiotics reduce the numbers of some species, you may notice loose stools, extra wind or a feeling of fullness for a while.
I work alongside your doctor, who is the right person to look into symptoms that do not settle, and I would always want you to see them promptly if you notice blood in your stool, unexplained weight loss, signs of anaemia such as unusual tiredness or pallor, a lasting change in bowel habit, or new digestive symptoms over the age of 50.
Aim for Plant Variety
Different gut bacteria thrive on different fibres and plant compounds, so variety is the theme. Many people find it helpful to think in terms of different plant foods across the week, including vegetables, fruit, nuts, seeds, whole grains, pulses, herbs and spices, rather than focusing on a single food.
Rather than overhauling your diet overnight, add a little more variety each day so your gut has time to adjust. Raising your dietary fibre gradually provides fuel for the bacteria that live in your large intestine, and drinking enough fluid helps fibre do its job comfortably.
Prebiotic and Fermented Foods
Prebiotics are the fibres that feed your gut bacteria, while fermented foods contain live micro-organisms. Food-first, many people include a little of both. To see how they complement one another, read my guide on probiotics vs prebiotics.
Foods you could include as they suit you:
- Kefir or live yoghurt: Fermented dairy foods that contain live cultures.
- Garlic, onions and leeks: Natural sources of prebiotic fibre. Start small if these tend to cause wind.
- Oats and sourdough: Wholegrain choices that add fibre to everyday meals.
- Sauerkraut and kimchi: Choose unpasteurised, chilled versions if you want live cultures.
- Flaxseeds and chia seeds: Easy additions to porridge or yoghurt that add fibre.
Be Gentle With Your Gut
While your digestion is settling, many people find that very rich, heavily processed meals and large amounts of alcohol feel less comfortable. Simple, home-cooked dishes such as soups, stews and cooked root vegetables are often easier on the digestion than big raw salads, and you can bring the variety back in as you feel ready. For wider context on how gut microbes influence wellbeing, explore my article on microbiome health, and see how everyday eating habits can support your gut health.
Making It Work for You
You may have seen advice to start a high-dose probiotic the moment a prescription ends. The evidence on supplements is mixed and varies by product, so I focus on food first and keep supplement decisions general. Every gut is different, and what feels comfortable for one person may not for another.
If you would like help building a varied, gut-friendly way of eating that fits your routine and tastes, I offer food-focused support through my online consultation service. Take a look at my nutritionist services or head to my contact page to book your first appointment.
