Before we weighed them, parents completed a written questionnaire asking them to estimate their own and their child's weight on a five point scale ranging from “very underweight” to “very overweight.” Responses indicating level of concern about weight were similarly ranked from “very worried about underweight” to “very worried about overweight.”

Children and parents were significantly heavier than UK norms (table): 52/277 (19%) children, 141/273 (52%) mothers, and 165/230 (72%) fathers were overweight (including obese). Among overweight parents, 40% mothers (45% fathers) judged their own weight “about right” and 27% (61%) were unconcerned about their weight.

Only a quarter of parents recognised overweight in their child. Even when obese, 33% mothers (57% fathers) saw their child's weight as “about right.” Parents were less likely to identify overweight in sons than daughters: only 27% of overweight or obese boys were classified as at least “a little overweight,” compared with 54% of overweight girls (P = 0.01). More mothers than fathers correctly assessed their child's weight (84% v 76%, P = 0.06).

Maternal weight status did not affect mothers' awareness of their chidren's weight: 82% of overweight mothers were correct compared with 82% of normal weight mothers (P = 0.50). However, only 74% overweight fathers were correct compared with 85% normal weight fathers (P = 0.08).

More than half of the parents of obese children expressed some degree of concern about their child's weight, but only a quarter were even “a little worried” if their child was overweight. Most parents (86%) who were unaware that their child was overweight, were also unconcerned about their child's weight. One in ten parents expressed some concern about underweight in normal weight children.

Acknowledgment of excess weight and an understanding of its health consequences are essential first steps in tackling obesity. The layperson's perception of average weight, however, now conflicts with the clinical definition of normal weight, and a label of overweight from a health professional may be insufficient motivation for a change in lifestyle. The apparent lack of parental concern about their child being overweight probably stems from a lack of awareness. Until this is resolved, we are missing critical partners in our efforts to stem an impending health crisis.