If you are of a sensitive nature you may want to look at some of the other topics covered in my column – I’ll understand. But never let it be said that this column shies away from the more embarrassing or squeamish subjects when it comes to debunking myths. And the folklore surrounding haemorrhoids is a good case in point.
When it comes to haemorrhoids, or piles as they’re often known, there are two things that we can say about them with some confidence. First, we can say that this is a surprisingly common condition: as many as 50% of people will suffer from piles at some point during their life. Second, it is also fair to say that the old wives’ tale that piles are caused by sitting on cold (and often wet) surfaces bears little truth on examination.
Before exploring the evidence available, it’s worth explaining what the condition actually is. Piles or haemorrhoids are itchy, bumpy swellings that develop from the cushions of tissue lining the anal canal. They can sometimes be felt as soft lumps outside the body – leading some people to compare them to a small bunch of grapes. When this happens sitting on hard surfaces can be uncomfortable, and I wonder whether this is the root of the myth. But since cold packs are one way of relieving the pain, particularly if a blood vessel has developed a hard clot, then if anything a cold surface could be helpful.
Very few studies have looked specifically at the relationship between temperature and the prevalence of piles. But a German study conducted in 2009 investigated sitting on cold surfaces as part of a long list of possible factors. They compared two groups of people: One group was suffering from the painful condition where haemorrhoids have extruded from the body and hardened. The other was not. Looking at everything from lifting heavy loads to coughing, sneezing, eating spicy meals and using wet wipes after a visit to the toilet, none of these, not even sitting on cold surfaces appeared to make any difference to a person’s likelihood of getting piles. (The link to the study can be found here, but be warned that it contains graphic images).
While piles are nothing to do with sitting on hot or cold surfaces, or seemingly any other factor investigated in the German study, we can at least say why this particular part of the body is prone to the condition.
As family doctor, Ann Robinson put it to me: “It just happens to be a weak spot in the body.” The reason is that the anal canal is a place where three different systems of veins meet up. A little swelling in these veins can be useful because they dilate the small cushions, and can help to seal off the anal canal, preventing faecal incontinence. But if they become too swollen they can project into the anal canal and this is where the discomfort and pain starts. They can also cause bleeding, and if this is the case this should be checked out by a doctor because it can also be a symptom of bowel cancer.
Anything that increases can congestion in the pelvis, such as pregnancy, makes piles worse. Constipation causes pressure on the veins and can result in a person straining so hard that the piles pop out, leading to pain that can become severe.
But there is some welcome news. There is evidence for how best to prevent the condition from happening in the first place. The German study found that people who had frequent baths or showers were less likely to develop piles, while those who strained a lot while they went to toilet were at increased risk. Anything that avoids constipation can help – eating plenty of fibre such as vegetables, cereals and nuts, taking exercise to remain at a healthy weight and drinking water.
It’s also important to go to the loo when you need to rather than holding it in. Which brings up one last thing: it’s probably not a good idea to read this column while sitting on the toilet. Studies suggest if you read on the toilet you are likely to stay there for longer than you realise, encouraging you to sit and strain. And this column is designed to shed light on, not be the cause of any medical condition.
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You can hear more Medical Myths on Health Check on the BBC World Service.
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