Cannabis use in middle age 'doesn't lead to mental decline'
- Scientists said casual cannabis users performed better on memory test
- They said this could be because they generally had a higher education level than non-users
Middle-aged adults whose memories have grown hazy can't blame smoking cannabis for their forgetfulness, according to researchers.Scientists from King's College, London, found occasional pot use could actually improve concentration levels although they stressed that long-term use could be harmful.
The study, carried in the American Journal of Epidemiology, tested the mental function and memory of nearly 9,000 Britons at age 50 and found that those who had used illegal drugs as recently as in their 40s did just as well, or slightly better, on the tests than peers who had never used drugs.
Cannabis was by far the most common indulgence for the participants - who were surveyed at age 42 about current or past drug use, then tested at age 50 - with six per cent saying they had used it in the past year, while one-quarter said they had ever used it.
Between three and eight per cent said they had ever used other harder drugs including amphetamines, LSD, hallucinogenic mushrooms, cocaine and ecstasy.
'Overall, at the population level, the results seem to suggest that past or even current illicit drug use is not necessarily associated with impaired cognitive functioning in early middle age,' said lead researcher Dr Alex Dregan.
'However, our results do not exclude possible harmful effects in some individuals who may be heavily exposed to drugs over longer periods of time.'
A small subset of participants who said they had ever been treated for their drug use, which could suggest heavy or addicted drug use, did not fare as well cognitively at 50, but there were too few of them to draw meaningful conclusions, the study authors noted.
Dr Dregan's team used data on 8,992 42-year-olds participating in a UK national health study, who were asked if they had ever used any of 12 illegal drugs. Then, at the age of 50, they took standard tests of memory, attention and other cognitive abilities.
Overall, the study found, there was no evidence that current or past drug users had poorer mental performance. In fact, when current and past users were lumped together, their test scores tended to be higher. http://www.dailymail.co.uk/health/articl...al-decline.html