February 8/Bristol, England/Canberra Times -- A British study suggests toddlers who eat a lot of processed food may have a lower IQ as adults.

The findings, the result of one of Europe's largest public health research projects, have revived an Australian push to ban fast-food advertising during the hours children watch television.

The study followed 14,000 English children born in 1991 and 1992 whose health was monitored at the ages of three. four, seven and eight.

Three dietary patterns emerged: a diet high in processed fats and sugar; a "traditional" diet high in meat and vegetables; and a "health- conscious" diet with lots of salad, fruit, vegetables, pasta and rice.

The children's IQ was measured when they were eight, and there was a difference between those who had the "processed" and "health-conscious" diets in early childhood.

The children who ate the most processed food had an average IQ of 101, compared with 106 for those with a "health-conscious" diet.

One of the study's authors, University of Bristol senior research fellow Pauline Emmett, said, "It's a very small difference, it's not a vast difference.

"But it does make them less able to cope with education, less able to cope with some of the things in life."

The chairwoman of Australia's Coalition on Food Advertising to Children, nutritionist Kathy Chapman, said the findings suggested "far more must be done" to reduce children's exposure to fat and sugar-rich foods.

"We need policies that will make the healthy choices the easy choices," she said.

The federal government set up a preventive health taskforce last year that is monitoring how the food industry markets to children, but Chapman said self-regulation was inadequate and open to abuse, as nominated "children's hours" were not when most young people watched television.

"It's not just about kids' shows: we also need to limit their exposure to fast-food ads when they're on the internet, when they're outside and when they're watching sport," she said.

Public Health Association chief executive Michael Moore warned self-regulation of fast-food ads was "simply not good enough."

"Where there are significant impacts on health, the government needs to intervene," he said.

He said the government's first step should be targeted bans on junk-food marketing.

Associations between IQ and nutrition are often strongly debated because they can be skewed by socio-economic factors.

Wealthier parents, for example, may be more likely to prepare healthier meals, or be pushier about stimulating their child, than poorer parents.

However, Emmett said the research team took special care to filter out such confounders.

From the February 21, 2011, Prepared Foods E-dition