"Good wholemeal bread can provide four to five sources of dietary fibre, such as wheat bran, oat bran and seeds, and each one stimulates the growth of a different variety of gut bacteria."
Professor Barbara Ryan, consultant gastroenterologist at Tallaght University Hospital and co-founder of The Gut Experts, takes us through her pillars of good gut health.
I leave the house early, bringing my breakfast to work. Today, I had a slice of homemade bread. Good wholemeal bread can provide four to five sources of dietary fibre, such as wheat bran, oat bran and seeds, and each one stimulates the growth of a different variety of gut bacteria.
Research shows that cutting out wheat and gluten from your diet can cause a reduction in the numbers of probiotics in our gut, so I don’t recommend going gluten-free unless you’re coeliac.
I also had a semi-ripe banana (riper ones are higher in fructose which can cause bloating) and some natural yoghurt for good, healthy bacteria. I have coffee, too, which contains fibre and polyphenols that benefit gut bacteria.
Exercise is an important part of my life. Increasingly, science shows that activity is good for the gut and microbial diversity. It doesn’t need to be high-octane – even 30 minutes of walking, five times a week, is proven to benefit conditions like IBS which now affects one in 10 adults.
If you’re sitting at work all day, taking a walk not only gives you a chance to pass wind (we all have the need!), it stimulates gut motility, helping a sluggish bowel. I aim for three to four gym sessions a week. On weekends I take beach walks – I live in a lovely seaside town called Skerries, 20 miles north of Dublin.
When I’m busy doing procedures, lunch can be a moveable feast, but I make sure to sit quietly for a few minutes. Eating too quickly means you tend to swallow more air which can lead to bloating.
I like a homemade sardine salad or chicken wrap, plus fruit and yoghurt. The body likes routine so eating meals followed by three- to five-hour fasts is beneficial. When you’re hungry and your stomach rumbles, it’s called a “housekeeping wave”, a strong peristaltic wave that goes from the top of your stomach all the way through to your colon (like a Mexican wave for your bowel), clearing out debris and undigested matter and helping the integrity of gut bacteria. Grazing isn’t good for your microbiome.
We have a great fish shop locally so we tend to eat white or oily fish a few times a week. Omega-3 fish oils have been shown to increase gut microbiota diversity. We like lots of vegetables.
Grazing isn’t good for your microbiome.
We should all be getting plenty of plant-based foods – fruit, vegetables, grains, nuts, herbs, spices. Each piece of plant-based food contains a specific blend of nutrients that supports the proliferation of a particular species of healthy gut bacteria.
We don’t really have desserts but I do love cheese, it’s a fantastic fermented food for the gut, a great source of bacterial diversity and generally well tolerated. We eat dinner by 7.30pm. It’s known that eight to 10 hours of fasting overnight is good for the gut microbiome. As I like to eat breakfast, I try to finish dinner by 8pm to give my gut a good break.
I don’t drink during the week but I do like a gin and tonic. Alcohol is a bowel stimulant so if you have a condition such as IBS, even the smallest amount may set off your symptoms.
The gut tends to tolerate white spirits better than higher-fructose drinks, such as rum and fruit cocktails. Research suggests one or two glasses of red wine can benefit the gut microbiome as it contains polyphenols that stimulate beneficial bacteria.
However, excess alcohol can cause gut dysbiosis and the more you drink, the greater your risk of every digestive-system cancer. The less alcohol you consume, the better.
Like many people, I struggle with sleep. We’re often hyper-alert and hyper-connected when we should be switching down. I aim for six to seven hours’ sleep but, ideally, we should get seven to nine.
Studies show a positive correlation between sleep duration and quality and gut bacterial diversity, but people with conditions such as IBS often sleep badly due to uncomfortable symptoms, so it’s a bit chicken and egg.
I don’t take probiotics. Your gut microbiota is like a meadow of wildflowers (each one stimulated by a different food fibre) so it’s simplistic to think a probiotic supplement with one or several varieties of bacteria is going to have an amazing effect on all that incredible meadow.
I don’t take probiotics.
Research suggests most probiotics don’t actually take root in the gut but are more like passengers so the effects, if any, may last only while you’re taking the probiotic. The best thing you can do for your microbial diversity is to eat plenty of plant-based foods, get adequate fibre, exercise, don’t drink too much, don’t smoke, and try to get enough sleep. All those things are far better for you than taking a probiotic.
