Researchers from University College London's Institute of Child Health said that doctors have an opportunity to assess whether a child is overweight as children tend to use primary care services around once every year.
The researchers claim that a 'disease burden' is being put on the population by overweight children, with parents often not recognising the fact that their loved ones are obese.
Professor Russell Viner and research fellow Lee Hudson were writing in response to a study published in the British Medical Journal by Oxford University researchers, which found that obese children are far more likely to have a stroke or a heart attack when they are adults than those of a normal weight.
"The current review provides a stark illustration of the probable threat childhood obesity poses to disease burden in the population," Professor Viner and Mr Hudson said.
"Opportunistic measurement of BMI in primary care may be a useful first step in helping families move towards tackling childhood obesity."
Childhood obesity is likely to cause future health problems for Britain's youngsters. Developing into an obese adult brings with it a greater risk of heart disease, diabetes and high blood pressure.
More on Parentdish: