
Selles - qu'est-ce qui est normal ?
Revu par Dr Krishna Vakharia, MRCGPDernière mise à jour par Victoria RawDernière mise à jour 7 Aug 2024
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Déféquer est une fonction corporelle essentielle. Il existe une grande variété dans la fréquence à laquelle nous déféquons et dans la consistance de nos selles. Alors, quelle fréquence - ou quelle rareté - est normale et quand faut-il consulter un médecin ?
Your poo is affected by a huge range of factors. Some of these you can't influence. Even if we eat an identical diet, some people would open their bowels more often than others. And no matter how much you want to, you can't influence ageing - de la constipation becomes more common with age.
Some of this is down to being less active or having a higher chance of taking medication that slows your needing to have a poo down. But with age, your gut may move digested food along less efficiently.
How many poos a day is normal?
Most people have a fairly regular pattern of going to the toilet. Most of us go between 3 times a day and 3 times a week. Many people tend to go at about the same time every day.
Some medical conditions - such as la maladie inflammatoire de l'intestin (maladie de Crohn et la colite ulcéreuse) ou maladie diverticulaire - can lead to frequent, loose poos. But if you don't have an underlying medical condition that affects many of the factors that determine how often you open your bowels relate to your diet and lifestyle.
Activité physique helps stimulate co-ordinated movements of the rings of muscle around your bowels that propel food through your digestive system (peristalsis). So being physically active doesn't just strengthen your heart and lungs - it can help keep you regular too.
What can affect the consistency of poo?
Many medicines can cause looser poos or constipation as a side effect - common examples include:
Codéine-based painkillers, sometimes called opioïdes - this includes combination painkillers such as co-codamol and co-dydramol, as well as very strong painkillers such as morphine.
Certains antidépresseurs. Tricyclic antidepressants such as amitriptyline are more likely than other types to cause constipation - these are often prescribed not just for depression but for nerve pain, such as trigeminal neuralgia ou postherpetic (post-shingles) nerve pain.
Some medicines used for vessie hyperactive.
la maladie de Parkinson treatments.
If you're taking medication and you feel it might be linked to constipation, your pharmacist will be able to help you.
Your poo is made up of a combination of food that hasn't been absorbed into your system, waste products, and bacteria that live naturally in your gut and water. Changes to your diet and lifestyle can alter all of these.
Fibre in your diet - wholemeal and whole grain foods, vegetables, fruits, pulses, beans and lentils are all good sources. These help bulk out your poos, allowing you to go more regularly and with less straining.
If you're dehydrated, more water from your gut will be reabsorbed into your system. This makes poos smaller, harder and more difficult to pass.
How to get rid of constipation
Constipation is a common reason for people to see their doctor. It's often a long-term problem, which can be helped by making changes to your level of physical activity, as mentioned above. But if you're unwell for another reason, you may have a fever - which makes you lose more fluid - be less active, go off your food and take medicine such as strong painkillers, which can all lead to constipation.
Bowel movements and IBS
Syndrome du côlon irritable (IBS) can cause bloating and tummy pain as well as constipation, diarrhoea or a combination of the two. It's a functional bowel problem. This means there's no abnormality in the structure of any individual bit of your gut, but the various parts don't work smoothly together.
Lifestyle changes and medication can help. You may be referred to a dietitian to help find foods that don't cause symptoms, but still allow you to get all the nutrients you need. Never assume your symptoms are down to IBS if you've never had them before. Speak to your doctor, who may arrange investigations to exclude other causes.
Causes of diarrhoea
Tummy bugs et intoxication alimentaire are the most common causes of diarrhée. Other symptoms which often go hand in hand with the diarrhoea include feeling - or being - sick, tummy cramps and sometimes fever. Most of these settle within a few days without complication.
However, changes in your poos or going to the toilet that do not settle, or that are accompanied by any 'red flag' symptoms, should always be checked out by your doctor. That's because it could be a warning sign of cancer of the bowel.
Les symptômes à surveiller incluent :
Perdre du poids sans le vouloir.
Being off your food.
Severe or persistent tummy pain.
Problems swallowing, or severe pain on swallowing.
Vomissements persistants.
Se sentir très fatigué ou avoir l'air pâle.
Also, you'll usually need to be referred straight for medical assessment at the hospital if you experience:
Vomiting blood or black 'coffee grounds'.
Passing blood in your poo or black, tarry poos.
Bowel screening
Across the UK, the NHS will send you a home bowel screening test kit - faecal immunochemical test (FIT). You collect a small sample of poo, send it to a lab and they will check it for any blood which can be a sign of polyps or bowel cancer.
You will receive your FIT kit at different ages depending on where you are in the country:
England - 54 to 74-year-olds. This is now being expanded to include people aged 50-53.
Northern Ireland - 60 to 74 year olds.
Scotland - 50 to 74 years.
Wales - 51 to 74 years. This is being expanded to include 50 year olds in the future.
Avec remerciements au magazine 'My Weekly' où cet article a été initialement publié.
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À propos de l'auteurVoir la biographie complète

Dr Sarah Jarvis
Consultant Clinique
MA (Cantab), BM, BCh (Oxon), DRCOG, FRCGP, MBE
Après avoir suivi une formation en médecine à Cambridge et Oxford, le Dr Sarah Jarvis MBE est devenue médecin généraliste.
À propos du critiqueVoir la biographie complète

Dr Krishna Vakharia, MRCGP
Médecin-chef pour la santé, Optum UK
MBChB, MRCGP(2013), BMedSci (hons), DFSRH, DRCOG, PGDipDerm (Distn)
Le Dr Krishna Vakharia est un médecin généraliste du NHS. Elle est également examinatrice régulière pour le diplôme de troisième cycle en dermatologie pratique à l'Université de Cardiff, ainsi que médecin-chef pour la santé chez Optum UK.
Historique de l'article
Les informations sur cette page sont examinées par des cliniciens qualifiés.
Article également disponible en Anglais, Allemand, Espagnol, Français, Italien, Portugais, Hindi, Hébreu, Arabe, and Suédois.
Prochaine révision prévue : 8 août 2027
7 Aug 2024 | Dernière version
26 Sept 2022 | Publié à l'origine
Écrit par :
Dr Sarah Jarvis

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