Parents could have created health problems in later life for their babies by overfeeding them because charts used to measure their growth were based on wrong assumptions two decades ago, the World Health Organisation said yesterday.
The growth charts used in every baby clinic in the country were drawn up in the US, but have now been found to have been based on babies fed mainly on formula milk.
Based on those figures, babies who are breastfed can appear to be growing poorly from as early as two or three months old when they are in fact perfectly healthy.
A new seven year study carried out by the WHO shows babies who were exclusively breastfed for six months are healthier and leaner than those who hit the norm on the current growth charts.
The WHO study, carried out in collaboration with the United Nations University, shows that recommended weight gain based on breast-fed babies would be 7% less.
This has led to fears that the old charts could be playing a part in the obesity epidemic.
Now the WHO is to draw up new charts and scrap the old measures, causing a potential revolution and possibly a furore among health visitors and paediatricians.
It is not compulsory for countries to accept the recommendations of the WHO, but Mercedes de Onis of the department of nutrition and author of the research, is confident they will.
"I'm convinced the whole world will use them over a period of time," she said. The changeover would be slower in countries like the UK which have set standards. "It's like replacing the pound with the euro."
She anticipates that paediatricians will act before governments do. "I think when [the new charts] are on the web, many, many paediatricians will download them and, no matter what the government thinks, they will use them."
The British government accepted the WHO's recommendation that exclusive breastfeeding for six months is the best start in life, but most babies begin to slip below the mean on the growth charts from two to three months old. Mothers have usually been advised to start adding bottlefeeds and weaning foods.
Not only is that not necessary, the WHO says now, but it may be fuelling the obesity epidemic.
There is growing evidence of a link between a baby's early growth and the later development of obesity-related diseases such as heart problems and diabetes.
At a conference in London organised by the WHO and the International Obesity Task Force yesterday, where the findings were presented, Ricardo Uauy, professor of public health nutrition of the London School of Hygiene and Tropical Medicine, said American babies could no longer be considered the healthy norm.
"Times have changed since the new generations in the US are now affected by the obesity epidemic," he said. Some of the babies on whom the growth charts were based were now part of it.
"A significant proportion of those children, presently middle-age adults, are suffering from nutrition related chronic disease ... it is questionable that the growth of US children should be considered 'optimal' in terms of life long health."
The WHO Multicentre Growth Reference Study collected data from 8,440 babies in six countries - Brazil, Ghana, India, Norway, Oman and the US - from 1997 to 2004.
