One in 10 children starting school in the UK are already obese,1 yet a recent government poll indicated that parents worry more about their children being murdered than they do about their health.2 How do we begin to raise awareness about the considerable risks that accompany obesity?

Not long ago I was approached by the Department of Health for my views on obesity prevention and the criteria health visiting services should be using to gauge unhealthy weight gain. At first thought it seemed logical to suggest a reversal of our criteria for weight faltering, namely to alert parents when their baby's weight crosses up two centiles or is above the 98th centile. However, a moment's reflection led me to consider that we might do better than this.

Recent epidemiological studies have identified a number of factors in the perinatal period that indicate risk for later obesity.3,–,8 The most significant of these are shown in box 1. I wondered whether these data might be used to develop a more ‘evidence-based’ way of providing guidance on obesity risk than using growth charts alone?

The idea began to emerge that we might be able to develop a tool to identify a baby's risk. The benefits of doing so could be considerable. Families could be provided with guidance before obesity developed and health visiting resources could be targeted to focus on those most in need.