A French health watchdog has recommended that children under the age of six should not be allowed access to 3D content. The Agency for Food, Environmental and Occupational Health and Safety which has the unfortunately acronym (Anses) said that kids up to the age of 13 should only be allowed "moderate” use of 3D.

It follows research into the possible impact of 3D imaging on still-developing eyes. Few countries currently have guidelines about 3D usage. According to Anses, the process of assimilating a three-dimensional effect requires the eyes to look at images in two different places at the same time before the brain translates it as one image.

"In children, and particularly before the age of six, the health effects of this vergence-accommodation conflict could be much more severe given the active development of the visual system at this time," it said in a statement.

Italy has sought to restrict the use of 3D glasses by young children, following a similar warning from its national health agency last year. When Nintendo released its 3D video console in 2010 it warned that playing games on it could damage the eyesight of children under six.