Primary school teachers' beliefs and advice to parents concerning sugar consumption and activity in children.

The available body of scientific evidence does not support the notion that sugar consumption has significant adverse effects on children's behaviours; however, responses to a mailed questionnaire indicated that more than 80% of 389 Canadian primary school teachers believed that sugar consumption contributes to increasing activity of normal children and to the behavioural problems of hyperactive children. Moreover, in the previous three years, 55% of all respondents had counselled the parents of children whom they believed to be hyperactive to consider reducing their child's sugar consumption to control the child's activity, and parents frequently did so. These results indicate that teachers need to be provided with accurate and up-to-date information about the effects of sugar on children's behaviour and about effective treatments for hyperactivity. Possible origins of beliefs about the reputed adverse behavioural effects of sugar and about factors that may serve to perpetuate these beliefs are discussed.