posted on Jan, 14 2009 @ 02:53 PM
Here's an interesting article released by the NHS today.
Too much coffee can make you hallucinate and sense dead people,” says the Daily Express. This bizarre claim is based on research into 219 students
who answered questionnaires on caffeine intake, hallucinations and feelings of persecution. Various other news sources have reported the study,
including the Daily Mail, which says that “drinking cup after cup of coffee dramatically increases the risk of hallucinating”.
The study itself was investigating a theory that caffeine might heighten the body’s response to a hormone released during times of stress.
Researchers found that caffeine intake was linked to both stress and being prone to hallucinating. When results were adjusted to discount stress
levels, caffeine intake alone predicted tendencies towards hallucination.
However, this is preliminary research only, and as the authors state, the effect was only weak. Also, the questionnaire assessed the students
‘predisposition to hallucinations’, rather than their prior experiences of having actual hallucinations. The study’s limitations also mean that
it cannot prove that caffeine causes increased susceptibility to hallucinations; therefore it should not be a cause for alarm in people who drink
coffee or other beverages containing caffeine.
It should be noted the research paper contained no specific claims about the supernatural.
Where did the story come from? Simon Jones and Charles Fernyhough of the Department of Psychology, Durham University carried out this research. No
sources of funding were reported. The study was published in the peer-reviewed journal Personality and Individual Differences.
What kind of scientific study was this? This was a cross-sectional study designed to investigate the theory that the release of cortisol in response
to stress factors (or stressors) plays a role in the development of psychotic experiences. By extension, an individual’s propensity towards
psychosis may be expected to be in relation to their cortisol response.
Caffeine is believed to heighten the cortisol response to any given stressor. This investigation aimed to see whether, at a controlled stress level,
caffeine intake was related to hallucinations and ideas of persecution. Previous studies investigating caffeine and psychotic experiences have
produced mixed findings.
A total of 214 students (70% female; average age 20 years) were recruited, and filled in questionnaires on caffeine use. All respondents remained
anonymous and only age, sex and weight of the participants was known. Smokers were excluded.
The questionnaire on caffeine intake used a tool known as the Durham Caffeine Inventory, which presents caffeine-containing food and drinks and asks
respondents to rate their typical intake over the past year on a 12-point scale from none to 8+ times per day. Set values of caffeine content were
determined for each item, either from the FSA or sourced from the manufacturers.
The questionnaire also contained questions using the Launay-Slade Hallucination Scale, which is a 16-item tool designed to measure predisposition to
hallucinations on a 5-point scale from ‘certainly doesn’t apply to me’ to ‘certainly does apply’.
Persecutory ideas were assessed using the Persecutory Ideation 10-item Questionnaire (responses from ‘very untrue’ to ‘very true’). Stress was
assessed using the Perceived Stress 30-item Questionnaire, which looked at several aspects of stress, tension and worry over the past year (responses
‘almost never’ to ‘usually’).
Researchers then looked at the relationship between the level of hallucinations, feelings of persecution, stress reported, and caffeine consumption
per kilogram of bodyweight.