“For as long as IQ tests have existed, there has been a steady, progressive and ubiquitous improvement in the average scores people achieve at a given age, mainly because of a raising of the lower scores. On average, IQ is increasing by 3 per cent per decade. The effect is so strong that it implies that half of children in 1932, if given today’s tests, would score under 80 – the threshold for mental retardation.

Known as the Flynn Effect (after James Flynn), this phenomenon was initially dismissed as a result of changes in tests, or a reflection of better schooling. But the facts do not fit. Improvement is most marked in the types of test that relate least to educational content. Moreover, the effect is weakest in the cleverest children. It is a levelling-up phenomenon that results in a happy increase in equality.

After much agonising debate among psychologists, three explanations seem to make the most sense. The first is that (despite fast food) most children now get sufficient essential nutrients, vitamins, amino acids and oils to allow their Read the rest of this entry »