Spoon-feeding babies pureed food is unnatural and unnecessary, a childcare expert has warned.
Rapley says there is no need to feed babies pureed foods
Gill Rapley, deputy director of Unicef's UK Baby Friendly Initiative said feeding babies in this way could cause health problems later in life.
She said children should be fed only with breast or formula milk for six months, then weaned onto solids to improve control over how much they ate.
This could prevent babies becoming picky about food.
Mrs Rapley has spent 25 years as a health visitor, and she said: "I found so many parents were coming to me with the same problems - 'my child is constipated, my child is really picky' - and they couldn't get them on to second stage baby food."
From these observations and her own studies she developed her feeding programme, called Baby-Led Weaning.
According to this programme, during the first six months babies should receive milk only.
She said: "In 2002 the World Health Organisation backed research that found breast or formula milk provided all the nutrition a baby needs up to the age of six months.
"That research said feeding a baby any other food during the first six months would dilute the nutritional value of the milk and might even be harmful to the baby's health."
These findings have been incorporated into government recommendations on baby feeding.
After six months, Mrs Rapley said babies were capable of taking food into their mouths and chewing it.
Therefore, feeding them pureed food at this time could delay the development of chewing skills.
Instead, she said, they should be given milk and solid pieces of food which they could chew.
Mrs Rapley argued that babies fed pureed food had little control over how much food they ate, thus rendering them vulnerable to constipation, and running a risk that they would react by becoming fussy eaters later in life.
She blamed the food industry for convincing parents that they should give children pureed food.
She said: "Sound scientific research and government advice now agree that there is no longer any window of a baby's development in which they need something more than milk and less than solids."
Professor David Candy, a paediatric gastroenterologist with the Royal West Sussex NHS Trust, said this programme could be a good idea.
But he warned that it was difficult to set an exact age at which babies should be given solids, as individuals develop eating skills at different rates.
Purees could help some babies make the transition between liquid and solid foods more easily.
He said: "Some babies could manage this, but others may not have the oromotor skills necessary to chew the food - they would just push it out of their mouths."
Roger Clarke, director-general of the Infant and Dietetic Foods Association which represents members of the food industry, said the research needed to be looked at carefully.
But he agreed a "one size fits all" policy on baby-feeding was not appropriate.
He added generations of parents had relied on baby foods to provide a "safe, sound nutrition" for their babies.
A Unicef spokesperson said that Gill Rapley was speaking in a personal capacity, not on behalf of the charity.