TV Scope: Horizon - Could Fish Make My Child Smart? BBC2, Thursday, 6th October, 9pm.
As parents all over the State pour fish oil down their children's throats in the hope of boosting their IQ, the question arises - are they wasting their time?
That is the question this Horizon programme set out to answer. The answer it came up with was not definitive, but there was enough there to keep sales of omega-3 at a healthy level.
It is accepted that omega-3, most readily found in oily fish, is good for your physical health. People who have had a heart attack and who take a gram of omega-3 a day are less likely to die suddenly of heart disease, the programme told us.
The fatty acid was identified in the 1940s by Oxford University scientist Hugh Sinclair as being good for the heart.
At the time, the idea that fat could be good for us was so unacceptable that Sinclair lost his job at the university. He continued his study, undeterred, by putting himself on an Eskimo diet for a hundred days.
During that time he ate nothing but seal blubber and fish. He lost weight, rather than putting it on as might have been expected from a fat diet, but, more interestingly, he found that his blood had become very thin.
To Sinclair, this was the evidence he needed that omega-3 was good for the heart and that it worked by preventing the blood from clotting. But nobody was interested, and Sinclair died in obscurity. Since then, scientists have established that he was right about the beneficial effects of omega-3 in relation to heart disease.
But the claims made for omega-3 go much further. Some scientists maintain that omega-3 can fight depression.
This is based partly on the possibly dubious conclusion from American research that the lower the consumption of fish in a country, the higher its rate of depression. That is not a lot to go on, as there may be any number of reasons as to why depression is high in the countries concerned.
But what has pushed sales of omega-3 into the stratosphere is the claim that it can boost IQ. There is some interesting evidence concerning the effects of omega-3 on schoolchildren, but it is by no means conclusive.
Dr Madeleine Portwood conducted a study of 300 schoolchildren in Durham, half of whom were given omega-3 with the other half being given a placebo.
She found that those who had been given omega-3 were paying more attention in class at the end of the trial, that their abilities seemed to have improved and that their behaviour was better. They improved at reading and spelling. Children whose reading was a year behind their chronological age before the trial were reading above their chronological age after a year of omega-3 supplements.
The children who received a placebo also improved, but to a lesser extent. However, when they were put onto omega-3, they recorded similar gains to their peers.
Sceptics would point out that giving children the sort of attention they received in this trial is in itself likely to boost performance. It is a valid point - 300 schoolchildren is not a terribly big sample. Yet the results seem pretty dramatic and there is enough in them to encourage parents to go on administering omega-3 to their children.
Ultimately, the programme left us to make up our own minds about the IQ effects of omega-3 and about the value of shovelling fish oil supplements into our children to get a few vital extra Leaving Cert points.
Back in the 1950s, most Irish families observed the Catholic tradition of eating fish on Fridays. It was seen as a form of penance at the time so when the State modernised, we gave it up as an out-moded aspect of old-time religion. Maybe it's time to go back.
Padraig O'Morain is a journalist and counsellor.