Your saliva is possibly not something you have given much thought to – but it plays a vital role in maintaining good health, says Gordon Proctor, a professor in salivary biology at King’s College, London.
‘Saliva is a remarkable substance. It might be 99 per cent water, but it is far more than that,’ he says.
In fact, saliva carries the same bacteria found in your gut, as well as powerful substances that fight germs and promote wound healing – which might be why we instinctively pop our finger in our mouth if we cut or graze it.
Now, it is being used to detect serious disease. The University of California, Los Angeles recently announced that it had developed a £15 saliva test to spot early-stage lung cancer before it can be detected with a blood test.
The test looks for fragments of tumor DNA in a single drop of saliva, and can give a result in less than ten minutes.