We're all obsessed with our bowel movements - but have you ever considered what they're trying to tell you?

Blood in our stools is the tell-tale sign of bowel cancer, while changes in appearance can be a sign something sinister is up.

Now experts have come up with a chart which shows when stools are healthy and when you should be concerned.

Bowel or colorectal cancer is the third most common cancer in the world, with nearly 1.4 million new cases diagnosed in 2012 - the most recent figures to date.

But many people are reluctant to talk about their bathroom habits, new research has found.

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Examples of healthy stools are shown left, with possible changes in bowel habits, middle, and cases where you should consult a doctor immediately, shown right

Only half of those surveyed said they would discuss the subject with family - and even fewer would with friends, it emerged.

Bowel cancer consultant, Mr Ash Gupta, created the diagram with private healthcare providers Ramsay Health Care UK, to raise awareness of the symptoms.

Fewer than 10 per cent of people diagnosed at the latest stage of bowel cancer will survive for more than five years.

But if caught early, survival chances are significantly increased.

Mr Gupta said one of the most frustrating things about the killer disease is that so many deaths each year are preventable.

'The most difficult thing I have to grapple with as a bowel cancer consultant is the needlessness of many of these deaths,' he said.

WHAT ARE THE SIGNS OF BOWEL CANCER? Bowel cancer is very treatable but the earlier it is diagnosed, the easier it is. People whose cancer is diagnosed at an early stage have a much higher chance of successful treatment than those whose cancer has become more widespread. Symptoms include: Bleeding from your bottom and/or blood in your poo

A change in bowel habit lasting three weeks or more

Unexplained weight loss

Extreme tiredness for no obvious reason

A pain or lump in your tummy Source: Bowel Cancer UK Advertisement

'It is a fact that over 90 per cent of people who develop bowel cancer can be cured if caught early - at stage one.'

However warning signs of bowel cancer are often obvious in stools - and the chart has been designed as an easy guide to check for possible symptoms.

It shows healthy examples and advises people to check for changes, especially those that last for more than three weeks.

Stools that look dark - or tar-coloured - can be a sign of the disease, with patients advised to consult their doctor immediately.

'If changes in your bowel habits persist for more than three weeks, or if you have noticed blood in your stools, consult your doctor immediately,' Mr Gupta said.

'It is understandable that bowel symptoms may sometimes be embarrassing to be discussed and people may be put off by it, however it is crucial to get them investigated and treated early in order to achieve a cure.

'If you do notice bleeding in your stools - or persistent loose stools or increased frequency of stools - there are tests that need to be done.

'A camera test called colonoscopy - or sometimes even just an examination called a flexible sigmoidoscopy - may be required to diagnose and even treat early polyps at the same time.'

People can reduce their chances of getting bowel cancer by cutting down on alcohol, fatty food and meat as well as by increasing how much fruit, vegetables and fish they eat

Cases of bowel cancer are increasing with longer life expectancy.

By the age of 50 or 55, around 40 per cent of the population will have polyps on the bowel.

Only 10 per cent of them turn into cancer, but if the polyp is removed, so is the risk.

The most effective way to reduce the risk of bowel cancer is to investigate any symptoms and take part in screening programmes when invited to.

At the moment, only 50 per cent of people take up the offer of screening, which experts say is needlessly costing lives.

Studies have shown up to half of cases could be prevented by eating and drinking healthily, being physically active and maintaining a healthy weight.

This is supported by the trend that about 54 per cent of bowel cancer cases occur in more developed countries.

Ninety per cent of bowel cancer patients are aged over 50 and the disease affects slightly more men than women.