[url=http://www.cmaj.ca/content/182/12/E610.full]HERE[/url]
It suggests that today's recommendations are based on work of more than a decade ago. In turn, that work had a lot of its basis in assumptions about minimum intake to avoid (not prevent) disease, rather than optimal levels for good health. It appears that the data on which the assumptions are based is poor quality and not much work has been done to fill the gaps. I'm assuming that UK organisations and North American ones pay a degree of attention to work done in the other countries so I wouldn't expect Canada to be seriously out of step with the UK.
It suggests that today's recommendations are based on work of more than a decade ago. In turn, that work had a lot of its basis in assumptions about minimum intake to avoid (not prevent) disease, rather than optimal levels for good health. It appears that the data on which the assumptions are based is poor quality and not much work has been done to fill the gaps. I'm assuming that UK organisations and North American ones pay a degree of attention to work done in the other countries so I wouldn't expect Canada to be seriously out of step with the UK.