ALSPAC - The Avon Longitudinal Study of Parents and Children, also known as "Children of the 90s", is a unique ongoing research project based at the University.

It enrolled 14,000 mothers during pregnancy in 1991-2 and has followed most of the children and parents in minute detail ever since.

Some of the strongest evidence in favour of fish in the human diet comes from the Bristol families who are part of the project.

The researchers looked at the scientific evidence for what the fish oil omega 3 can and cannot do and say that the fatty acid Omega 3, found particularly in oily fish, is an essential part of the human brain, and forms an important part of our normal diet.

The scientists in Bristol have shown that women who eat fish regularly during pregnancy tend to have children with better vision, cognitive development and behaviour.

But according to the researchers this is not to say that fish oil supplements should be taken routinely by schoolchildren themselves, as the only positive evidence so far comes from the diets of pregnant women, not of the children themselves.

The debate over Omega 3 all began some fifty years ago at Oxford University when one scientist was investigating the strange fat found in high quantities in oily fish.

Professor Hugh Sinclair then put himself on an Eskimo diet and for 100 days he ate minced seal and whale blubber.

He found that despite eating half a kilo of fat a day, he lost weight.

Sinclair's meals were packed with omega-3, which he believed could protect against heart disease.

Years later wide ranging studies have vindicated his early intuition: and omega-3, in high doses, has been shown to protect people from having a second heart attack.

The Children of the 90s project in Bristol was the first to identify the associations between a prenatal diet rich in fish oil, and neurocognitive development in ordinary healthy children.

They analysed the diets of 7,400 mothers and found that there was a subtle but consistent link between eating fish during pregnancy and children ™s subsequent test scores.

The researchers found that that pregnant women who ate oily fish such as sardines and mackerel had children whose visual development was better, and those same children reached the adult grade of depth perception sooner.

The children also had better language and communication skills by the age of 18 months.

A positive association which was also seen for breastfeeding.

The largest effect was seen in a test of the children ™s understanding of words at the age of 15 months.

Children whose mothers ate fish at least once a week scored 7 per cent higher than those whose mothers never ate fish.

In recent times there has some negative press regarding the effects of eating too much fish because of the toxins which may be present.

The researchers say that all their evidence suggests that in moderation it is an essential part of the human diet, especially during the later stages of pregnancy when the baby ™s brain is developing.

Large fish remain the richest sources of Omega-3 but are more likely to contain pollutants, such as mercury, therefore experts recommend pregnant women consume two portions of wild or organic salmon, trout or sardines a week.

For the vegetarians seeds such as flax, pumpkin and hemp are good sources of Omega-3 but large quantities need to be consumed to gain the same effect.

Oily fish is the richest source of DHA, a fatty acid which is an important structural component of neuronal membranes found in the brain.

DHA is also present in breast milk but not standard formula milks.

For further information see alspac.bris.ac/welcome/index.shtml