'Barcelona Diet Plan': Adiós to pre-colonoscopy hunger

In fact, you could even live on fish and chips for a couple of days.

At present, patients' diets are heavily restricted in the week before the test and need to be low in fibre, with anything dairy banned a day or two before, and only liquids and clear soup – and no milk – allowed in the previous 24 hours.

During this time, anyone attending for the test has to drink a powdered non-stimulant laxative dissolved in two litres of water.

The idea is to clean out the colon completely so remains of food do not obstruct the specialists' view when performing the test.

Medics in endocrinology, nutrition and the digestive system at the Hospital del Mar say the preparation is so unpleasant and leaves patients feeling so weak that many opt not to bother with a colonoscopy, even though this could save their lives.

But Dr Juana Flores, main author of the research report in Diseases of the Colon & Rectum magazine, says the team obtained successful test results on patients who had eaten a normal quantity of calories' worth of bread, rice, pasta or potatoes with chicken, turkey, pork, beef or fish, combined with dairy products.

“This not only improves patients' experience with colonoscopies, but also the results of the colonoscopy,” Dr Flores says.

“The generalised belief that it is essential to eat nothing solid the day before the test had very little evidence to support it. Despite this, it is an habitual practice in the majority of hospitals and clinics.

“Now, however, our research makes it very clear that this strategy is not very efficient at all.”

The investigation involved 276 patients, all of whom were due for a colonoscopy after having taken part in the nationwide bowel cancer screening programme.

Half of them followed the 'Barcelona Diet Plan', and the other half stuck to the usual régime.

Of those who ate normally, 96% achieved a sufficient colon-cleaning to allow them to have a test with accurate results, compared with 89% of those who followed the liquid diet.

Those on the 'Barcelona Diet Plan', naturally, felt less hungry and empty at the start of the test, and had less of a sensation of being 'full of fluid'.

Both groups of people still took the two litres of liquid laxative, and the research team believes eating normally may make it easier to stomach and also gives the medicine 'something to work on' when clearing out the contents of the intestines.

The new diet plan is already part of the programme at the Hospital del Mar, and the digestive medicine department says patients' tolerance of the entire test process is vastly improved as a result.

With greater tolerance, there is more chance people will be willing to go for the test, the hospital says.

A colonoscopy is not an inevitable result of the nationwide bowel cancer screening programme, but it can be carried out under sedation if required, making it far more comfortable.

The screening programme is aimed at all adults aged 50 to 69 inclusive, who are invited, every two years, to send a stool sample to their local health centre.

If traces of blood are found – and these are frequently invisible to the naked eye – the patient is called for a colonoscopy.

Blood is found in fewer than 5% of samples, and even then, this does not mean cancer, as it can be a result of minor injury through straining or from haemorrhoids inside the rectum where the patient would not notice them.

During the colonoscopy, pre-cancerous cells, and polyps – which sometimes develop into cancer after many years – are painlessly removed during the exploration.

The programme also allows malignant tumours to be found at a very early stage and removed with minimum follow-up treatment and a near-guarantee of a complete cure.

Younger adults are often placed on the scheme automatically if they have a family history of bowel cancer.

The take-up rate among those eligible is low – fewer than 50% - largely through misconceptions, such as a fear of cancer being discovered, believing it involves a colonoscopy from the beginning and that this would be painful, or in some cases, embarrassment, even about handing in a stool sample to the health centre.

Local clinics are working hard on campaigns to dispel the myths and urge those eligible to take up the offer, since bowel cancer is one of the few that can be prevented, or detected at a very early stage.