People don’t think their child is overweight and they will grow out of it, when we know that’s not really trueProf Paul Aveyard Prof Paul Aveyard, Professor of Behavioural Medicine from Oxford University, said: “It gets round the problem that people don’t think their child is overweight and they will grow out of it, when we know that’s not really true. It’s quite a striking result and it’s cost free.”Prof Susan Jebb, a Government advisor on obesity, said the future projections were key to giving parents a wake-up call.“Seeing it projected forward [to adulthood] really personalises it for your child,” said Prof Jebb, a nutrition scientist from the Oxford University.“If you can show what your child looks like as an adult you can think ‘this is the kind of person who looks like they’re going to have a heart attack,’” she added.Chris Snowdon, Head of Lifestyle Economic at the Institute of Economic Affairs, said: “Parents can recognise whether their children are overweight without intrusive nannying from their GP. “Doctors should already be identifying obesity and warning of the associated health risks, regardless of age. Initiatives like these waste time which the NHS simply cannot afford.” After close examination from every angle, they were asked to pick which one was most like their own child.The studies found parents routinely underestimated the size of their offspring, commonly assessing them to be the same bulk as a far slimmer child.When they were then shown a further model, showing what their child would look like as an adult, based on their current Body Mass Index, families were shocked into making major changes. A year later, those subject to the intervention weighed nine pounds less than those who were not.Lead researcher Dr Angela Jones, from Newcastle University, said: “Parents play a key role because of how they shape children’s health behaviour.”They are also relied upon to recognise that their children is an unhealthy weight and take appropriate action. But we know that parents tend not to recognise when their children is overweight or obese.”She said parents tended not to realise their children were overweight because they would compare them with others in the playground, not realising how common it was for pupils to weigh too much.Experts said the tool was a way to demonstrate to parents that children were unlikely to “grow out of” weight problems, and were on course to become overweight or obese adults.It has now been tested in 15 areas, with proposals to roll it out on the NHS’ main website, for GPs and families to use. The NHS is to use shock tactics in an attempt to scare parents into tackling their child’s looming obesity.Parents will be shown 3D models showing just how overweight their child is set to become by the time they reach adulthood.Trials involving almost 3,000 children have found that the forecasts terrified families into taking action. In the pilot schemes, parents of children aged five and six were asked to key in their child’s measurements.They were then asked to watch a series of 3D graphics, showing a child their own age, digitally manipulated to look underweight, normal, overweight or obese. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.