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The Guardian - UK
The Guardian - UK
Lifestyle
As told to Elle Hunt

No, you don’t have to poo every day: eight things nutrition experts want you to know

‘Eat five different coloured fruits and vegetables every day.’
‘Eat five different coloured fruits and vegetables every day.’ Photograph: OatmealStories/Getty Images/RooM RF

You don’t have to poo once a day

It’s a widespread misconception that we need to open our bowels every day, first thing in the morning. People worry, but there’s a big variation between individuals – it’s just not something that they want to talk about. What’s really important is knowing what’s normal for you: everybody should monitor their bowel function as part of looking after your digestive health.

The first thing to be aware of is frequency. It’s normal for individuals to open their bowels anywhere from three times a week, to up to three times per day. What’s really important is that people know what’s normal for them, so that if anything changes, they can talk to their doctor.

The colour and consistency of the stool is also important. It may vary slightly day-to-day, depending on what people eat, but the colour should be a chestnut or mid-brown, and the consistency should be smooth like a snake or a sausage. It should be easy to pass as well. Guts UK!’s online Poo-Torial tool helps you to make sense of your bowel movements. If they are yellow or greenish, or greasy and difficult to flush, that can mean that people are possibly not absorbing nutrients. If diarrhoea and constipation symptoms persist for longer than three weeks, or if people find blood in their stool – they should go to their GP.
Julie Thompson, information manager, Guts UK! charity


There is no shortcut to finding out which foods you’re sensitive to

There’s a lot of confusion around the difference between food intolerance and food allergy. Often a patient will ask for a test that will tell them what foods they are sensitive to, but there isn’t one. We can test for coeliac disease, which is when people have an immune-mediated allergy to gluten and have to go on a gluten-free diet. About one in 100 of the population are true-blue coeliacs, and it’s really important that they are diagnosed. But many more people just feel a bit gassy and uncomfortable after eating bread products, or something else in their diet that is setting them off. The question is, how do you tease that apart?

Baker holding a fresh loaf
‘Many people just feel a bit gassy and uncomfortable after eating bread products.’ Photograph: pidjoe/Getty Images

One way is to follow an “exclusion diet”, where you eat very bland, comfort-type food for a few days. What that is depends on what you’ve grown up with or you’re used to: one person’s chicken soup might be another person’s pasta or dal or rice or chapati. After a few days, you gradually start to reintroduce your favourite food, one or two a day: coffee, red wine, a curry. Many people find that this gives them a much better understanding of what they are sensitive to. But if you don’t have any trouble and you feel fine, there’s no need. Life’s too short!
Prof Stuart Bloom, gastroenterologist, University College London Hospitals NHS Foundation Trust

That pain may just be wind

While I do a lot of bowel cancer screening colonoscopy, often patients will present with abdominal pain in the absence of any other symptoms and immediately think that it might be bowel cancer. Most of the time, it isn’t. Cancer doesn’t usually present with pain. (Think of breast cancer: somebody might incidentally come across a painless lump.)

More often, discomfort without other symptoms may be due to trapped wind. This often comes down to diet. High-fibre fruit and vegetables are great for reducing the risk of heart disease, stroke, type 2 diabetes and obesity, which make cardiologists very happy, but this healthy diet produces a lot of gas. This is due to the starches or sugars in those vegetables – fructose in particular (and lactose in dairy produce) – and are examples of what are collectively known as “FODMAPs” [fermentable oligosaccharides, disaccharides, monosaccharides and polyols]. I wouldn’t want patients to abandon the healthy diet but if they are having trouble, following a low-FODMAP diet will help with the pain of trapped wind.
Laurence Maiden, consultant physician and gastroenterologist, Maidstone and Tunbridge Wells NHS Trust, Kent

Gut health isn’t all-or-nothing, but make whatever changes you can maintain

A healthy gut microbiome is different for everyone – it’s like a fingerprint in the way that it stays more or less the same. Much of it is genetically determined: some of us have excellent microbiomes, and some are not so good, like those we believe may predispose us to have certain cancers. We can’t say with too much certainty what’s good or bad, or what’s the “ultimate” biome that we should be striving towards. What we do want to see in patients is many different populations of bacteria, not just several dominant ones.

You might think of your gut like a rock pool: it might look different at different times of the day, or as the seasons change, but the constituents of it change very little. It’s the same with your microbiome in your gut: it’s quite hard to work to improve it, and to maintain that improvement – but, on the flipside, you’ve got to work quite hard to cause significant damage. If you have a few big nights, your microbiome is going to recover, if you give it the opportunity. That’s why there’s the advice to take three to four consecutive days off drinking, not just to moderate our intake each day: our liver takes a bashing from alcohol and really needs a break.

But any changes have got to be sustainable. The gut likes structure. If you live the most virtuous lifestyle for your microbiome for a week, then go back to what you were doing before, you’re not going to have any benefit from those seven days. Make fewer lifestyle changes and habits, but ones that you can continue.
Dr Sean Preston, consultant gastroenterologist, Barts Health NHS Trust and London Digestive Health

Eat five different colours every day

There’s a lot of misinformation out there about how to care for your gut. I often hear patients say “I’ve tried this”, “I’ve tried that” and “What about probiotics?” But there are simple messages that would make a big difference.

The first is to eat five different coloured fruits and vegetables every day. For someone who is otherwise healthy, who hasn’t got problems with bloating and diarrhoea and the rest of it, a multicoloured, wholegrain diet feeds the good bacteria naturally.

Once that has become routine, you can refine. You can only buy wholemeal bread, and forget about white bread unless as a treat – then you can introduce nuts and seeds for snacking. It doesn’t matter which, so long as they are not salted peanuts.

Fermented foods are further down my list. The evidence is patchy: it does look as though it encourages bacteria, and it probably won’t do any harm, but it’s not a long-term solution. If the rest of your diet isn’t supportive, that good bacteria will just starve to death as soon as you stop eating sauerkraut. Prebiotic foods, such as oats and bananas, will help you to grow your own healthy bacteria in the colon naturally. Onions are good, too, but can cause bloating.

Probiotic supplements contain the actual bacteria themselves – of course, they won’t survive if you don’t feed them with a healthy diet, and some don’t contain enough live bacteria to work. For most people, they are unnecessary. When you put compost in your garden, the plants will grow; you don’t need fertiliser, and it’s the same in the gut.

The trouble is, taking a tablet is much more attractive than eating a banana – but more fruit and veg is a cheap and relatively easy lifestyle change. You could think of it like a sourdough starter: those good bacteria will grow if you feed them properly.
Dr Helen Fidler, consultant gastroenterologist, London Bridge Hospital

You can boost your good bacteria with exercise

Of course exercise is important for your general health, but there are so many advantages specifically for the gut. It improves the motility of muscles and the bowels, ensuring regular bowel movements. It also improves the bacterial balance in the gut – we don’t really understand why yet, but we think it’s to do with ensuring adequate blood supply. There is certainly good scientific evidence that exercise increases good bacteria, independent of what you eat. Exercise also improves the gut integrity through increasing antioxidant defence and reducing inflammation which, in turn, enhances the immune barrier function of the gut.

Couple running on beach
Chalk up another healthy win for jogging. Photograph: Chris Whitehead/Getty Images/Image Source

That’s not saying to give up on the healthy diet, but it shows that exercise is still important. We know very well that it reduces stress hormones and enzymes in the body, and boosts the hormones that improve mood, which is good for the gut. Finally, it also reduces the risk of many gut and digestive diseases such as liver disease and bowel cancer.

Non-strenuous exercises such as swimming, cycling, yoga and walking tend to be very good if you’re just starting out. Then, if you want to gain more benefit for your heart and lungs, you can go for higher intensity training such as running or weightlifting. However, doing strenuous exercise can also cause symptoms of acid reflux and upset the digestive system in some people, so you need to find a balance.

There has been a huge increase in people presenting with digestive problems, especially through lockdown, and a lot of it may well be related to reduced activity levels. Exercise alone can sometimes solve these problems.
Dr Sarmed S Sami, honorary consultant gastroenterologist, University College London Hospitals NHS Foundation Trust; founder and director, Digestive Health UK

IBD and IBS may sound alike, but they are very different

The two main types of inflammatory bowel disease (IBD) are ulcerative colitis and Crohn’s disease: these are lifelong and sometimes major inflammatory conditions affecting the gut. The important thing to note is that they are common, affecting about one in 100 people – and increasing as well. It’s really important to get a timely diagnosis, but often there can be a delay, because the symptoms can be vague.

Particularly in the case of Crohn’s disease, the symptoms can overlap with those of irritable bowel syndrome (IBS) like bellyache, fatigue, unintentional weight loss – the unintentional bit is important – and sometimes diarrhoea or an abscess around the bum. For ulcerative colitis, the symptoms can be more overt because there can be blood in the poo, or having to dash to the loo, both of which normally alert people that something is wrong.

But the symptoms can be different in different people, and they can come and go. People will think: “Oh, it’s stopped, I’ll leave it”. Likewise they might know someone with Crohn’s and think “I haven’t got that” – but it might be presenting differently for them. If any of those symptoms are present, even if they are coming and going, that is the moment to seek attention, the sooner the better.
Prof Ailsa Hart, consultant gastroenterologist and director of inflammatory bowel disease research, St Mark’s Hospital, London

Look after your mood, look after your gut

A full one-third of the world has some sort of disorder of gut-brain interaction. That might sound surprising but that includes things like IBS, as well as many patients with persistent heartburn, constipation or pain. The gut and the brain are so closely linked, you do need to take both into account.

It may sound obvious, but tackling stress is really important. Stress is really toxic to your gut: it increases the permeability of it, letting bacteria into your blood, and the more stressed you are, the worse the effect. Over time, the stressed gut becomes more sensitive to pain and vulnerable to changes in motility.

My other bit of advice is, if you think you’ve got clinical depression or anxiety, seek help. We’ve done some work on this: if you have clinical depression, you’re twice as likely to develop IBS, Crohn’s disease and colitis – but there’s also good evidence that if you’re on antidepressants, that reduces your risk. Talking therapies can also seem to restore the gut-brain axis, and may have an anti-inflammatory effect.

Beyond that, it’s important to take breaks during the day and get enough sleep at night. If you have ongoing insomnia, that’s putting further stress on your gut. A consistent early wakeup time helps, too, to get it moving. Plus it’s important to regularly schedule activities that pick your mood up.
Dr Calum Moulton, consultant psychiatrist, St Mark’s Hospital, London

• This article was amended on 22 March 2023. An earlier version said that about one in 300 people had coeliac disease. This has been changed to about one in 100.

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