Experts from Glasgow University examined the health of 52 retired Scottish male International rugby players and found little difference in cognitive tests compared to 29 volunteers.
The sport has attracted controversy in the past as repeated concussions have been linked to neurodegenerative disease and chronic traumatic encephalopathy, a progressive degenerative disease of the brain.
A group of top doctors called for a ban of full-contact rugby earlier this year, as they said the risk of serious injury was too high.
The study, which is published today in the Journal of Neurology, Neurosurgery and Psychiatry, revealed that despite multiple concussive injuries in the retired rugby players there were not significant effects on daily life overall.
Lead author Professor Tom McMillan, professor of clinical neuropsychology at Glasgow University, said: “Despite a high number of repeat concussions in the retired rugby players, effects on mental health, social or work function were not evident some twenty years after they had stopped playing.
“Overall there is not a suggestion of widespread decline in daily function in ex-rugby internationalists who had a high number of repeat concussions.
“Although some differences in memory were found, these were mild overall and their cause uncertain.”
In the first study of its kind, researchers examined general and mental health, life stress, concussion symptoms, cognitive function, disability and markers of chronic stress in 52 players, who reported they had suffered around 14 concussions each.
The former international performed less well on verbal reasoning and hand coordination than the non sportsmen, but cognitive tests showed few differences.
The research also found that there were no “significant associations” between the number of concussions and the participants’ performances on cognitive tests.