People with a higher caffeine intake, from sources such as coffee, tea and caffeinated energy drinks, are more likely to report hallucinatory experiences such as hearing voices and seeing things that are not there, according to the Durham University study.
‘High caffeine users’ – those who consumed more than the equivalent of seven cups of instant coffee a day – were three times more likely to have heard a person’s voice when there was no one there compared with ‘low caffeine users’ who consumed less than the equivalent of one cup of instant coffee a day.
The researchers, whose paper is published in the academic journal Personality and Individual Differences, say their finding could be down to the fact that caffeine has been found to exacerbate the physiological effects of stress. When under stress, the body releases a stress hormone called cortisol. It is this extra boost of cortisol which may link caffeine intake with an increased tendency to hallucinate, say the scientists.
"Hallucinations are not necessarily a sign of mental illness. Most people will have had brief experiences of hearing voices when there is no one there, and around three per cent of people regularly hear such voices."
You can read the entire article here.