The Flynn Effect: Kenya’s Rising IQ Scores
The developed world did not cure its health problems by benevolent outsiders applying bandages. They cured them by becoming functional modern societies. It is that whole package that caused the massive IQ gains of the twentieth century. -James Flynn
The Flynn effect is the observed rise in IQ scores over the last century discovered by James Flynn. In a series of research studies in the 1980s, Flynn was able to show IQ gains in the Stanford-Binet intelligence tests and the Wechsler intelligence tests of some countries. Even though these tests largely measure crystallized intelligence; which is the part of human intelligence that relies on acquired knowledge for problem solving, evidence also shows sustained gains in fluid intelligence, mostly measured by IQ tests such as the Ravens Progressive Matrices. These gains in IQ scores were observed in the developed world and recent evidence suggests that the developing world is en-route towards higher intelligence scores. This article is an answer to whether the measured low IQs in Africa will rise and how that process of IQ gains will pan out. However, for context, I’ll start by clearing some myths about IQ.
Heritability and Rising IQ scores
There are two misconceptions that tend to get in the way of any discussion on IQ. The first is the genetic basis of IQ and the second revolves around intervention measures to raise IQ. The heritability of IQ in the developed world has been placed at 0.80 for adults meaning a significant variance in intelligence in those countries is a result of genes. In the developing world, heritability is much lower meaning the resulting differences in IQ scores are less mediated genetically and thus mostly environmental. Since intelligence tends to have a high heritability, many people falsely conclude that intelligence is genetic and thus immutable.
To simplify by way of analogy, hemophilia is an inherited and genetic condition that causes unusual and prolonged bleeding due to blood clot failure. As an inherited condition, hemophilia remains immutable to those who get it from their parents and thus cannot be cured. Intelligence is caused by many genes each contributing a small effect to one’s overall intelligence. Since anybody can have any number of these genes, intelligence tends to vary between individuals and groups. Two different groups under similar conditions can have disparate levels of average intelligence, which allows calculations of genetic variation to be done. The result is what’s known as heritability.
The fact that two groups can have differences in their average IQ explained genetically does not mean that intervention measures to raise IQ in these groups will be futile. To wit, intervention measures act on average scores while genes influence the variance. This distinction is what tells us why the Flynn effect is possible in traits that are considered highly heritable like intelligence, obesity, personality, and psychopathology. Height is also a heritable trait which can be impacted by nutritional interventions. Group A with an average height of 6 ft and Group B with 5 ft could be treated to the same nutritional interventions raising their heights to 6.5 ft and 5.5 ft respectively. However, the variance and standard deviations between the two groups still remain since both groups underwent similar interventions and benefited equally. The one foot gap in average height between the two groups remains the same because the variation is influenced by genes. But the means changed and average heights increased.
Kenya’s Average IQ and the Flynn Effect
Kenya was the first country in the developing world where the Flynn effect was observed. Tamara Daley in a paper titled “IQ on the Rise: The Flynn Effect in Rural Kenyan Children,” gave results of a fourteen year intelligence project that started in 1984 and concluded in 1998 in Embu. The results indicated a 13.85 increase in IQ points on the Ravens Progressive Matrices over the 14-year period, and which Flynn observes is a “rate of gain of almost 1 point per year.” The resulting IQ rise in the children studied indicated a substantial increase from an average IQ of 69.89 in 1984 to an average IQ of 79.62 in 1998. Lynn uses the latter alongside average IQ scores measured in Kilifi, Nakuru, Nairobi, and Nyanza to come up with an average IQ of 75.20 for Kenya.
The IQ gain in Kenya was higher than had ever been observed in the developed World. The only countries that rivaled Kenya’s high rate of gain were Leipzig and France.
In a literature covering 15 nations or peoples, and these two rates lie well in the past. Children from Leipzig, then in East Germany, reported a rate that was marginally higher back in 1968 to 1978. Youths reporting for military service in France matched it back in 1949 to 1974, but only on paper. The French samples probably exaggerate gains by 5 points, which would reduce the rate to 0.805 points per year, which is in line with near-by Belgium” pg.56.
Kenya’s increases in IQ were larger in the Ravens Colored Progressive Matrices which is a culturally unbiased test of fluid intelligence. A smaller gain was observed in the verbal tests indicating lower increases in crystalized intelligence. Compared to other nations before and after their increase in IQ scores, Flynn observes that “in 1917, Americans had a mean IQ of 72 (against today’s norms) and a good estimate for 1900 would be 67.” Currently, the United States has an average IQ of 100 which shows an increase of more than 30 IQ points over the last few generations. The table below comes from Flynn and depicts some of the most recent IQ gains in the developed world.
From the box below, Flynn also shows how Kenya’s rate of IQ increase compares to that of other nations. Notice that only the Leipzig study beats it. He also shows how he arrived at 13.85 IQ points. The 4.49 raw score comes directly from Daley who found an increase of 4.5 points i.e 17.31 in 1998 subtract 12.82 in 1984. (These figures indicate the average raw scores on the IQ test i.e how many items they got right). Since raw scores say little by themselves, they have to be compared to similar samples from the same period and the standard deviations between both samples calculated and converted to IQ scores.
These IQ gains are not unique to Kenya. From these tables it’s evident that many more nations and jurisdictions have experienced some gains in IQ over the years. Daley attributed the Flynn effect to improved nutrition, higher literacy, improved health, and increased environmental complexities. The section below will try to explain which of these reasons might be the real drivers of IQ gains in Kenya and what interventions are the most appropriate.
Interventions to Raise IQ Scores
Countries can have low average IQs for many reasons most of them environmental. But a second myth persists regarding the Flynn effect and the rising of IQ scores. The fact that IQ has been observed to rise in nations such as Kenya is not evidence that individuals too can raise their IQs. Intelligence is determined by genes and as Russel Warne writes in “In the Know:”
If a person does not have enough of the versions of genes that boost IQ, then no environment — no matter how favorable — will make a person earn a high IQ on an intelligence test. Conversely, even the luckiest win in the genetic lottery is irrelevant if an environment is extremely negative, such as a childhood marred by long-term iodine deficiency, lead poisoning, famine, neglect, or severe brain injuries. Both genes and environment make their contributions to a person’s intelligence level.
Even though individuals can’t raise their IQs, Warne points to the possible influence of negative environments on intelligence. Most of these harsh environments such as lead poisoning and iodine deficiency are found in Africa and should be looked into as potential avenues for raising intelligence across the continent.
Lead Poisoning
Reducing lead poisoning is one way in which governments can intervene to raise IQ scores. Warne notes that in the 1970s, scientists noticed that “children with high levels of lead had lower IQ scores (4–5 points) than children with low lead levels.” In Kenya, various human settlements have been observed to have higher lead levels that pose severe health risks to residents. A research study in Owino Uhuru settlement had the following results as viewed from the abstract:
Children in Owino Uhuru live next to a lead smelter which explains the higher levels of exposure. However, these are not the only regions in Kenya with high levels of lead. A different study was conducted in Nairobi but which the authors do not disclose the exact location. It was of two companies that recycled batteries. The results show both had very high levels of lead in the air and blood samples of employees. Office employees were not exempt and also had very high levels of lead in their bloods. See the results below from recycling plant A.
The second plant had the following levels of lead:
These numbers obviously mean nothing if we do not know what’s the recommended level of lead exposure, if there’s any. According to a “Recommendation of the Advisory Committee for Childhood Lead Poisoning Prevention,” the CDC :
Uses a blood lead reference value (BLRV) of 3.5 micrograms per deciliter (µg/dL) to identify children with higher levels of lead in their blood compared to most children.
Using 3.5 micrograms per deciliter, it becomes evident that children in Owino Uhuru and Bangladesh settlements are exposed to already unhealthy levels of lead which could be having a significant impact on their IQs. The adults working in the aforesaid organizations are also exposed to astronomical levels of lead which may be harmful to them and their families.
Decreasing levels of lead exposure can have immense impacts on IQ. Russel Warne opines that after the United States banned the use of lead in fuel, pipes, and paint, the IQs of Americans increased by 9–12 points. He also cautions that “there is no known safe level of lead in the body, and even low concentrations of lead are associated with lower IQ.” To raise IQ scores requires that African countries ban or reduce the amounts of lead exposure to children. In Environmental economics, if an activity has more negative externalities to people and the environment than it has benefits, then there’s no point of pushing forward with it. A forward looking country wouldn’t mess with the IQs of its people.
Iodine deficiency
Another area of intervention for countries that want to raise IQ is iodine deficiency which Russel Warne believes could raise the IQ of children by around 8 points. He argues that:
Iodine deficiency is the most common cause of preventable intellectual disability in the world. The good news is that iodine deficiency is inexpensive to cure, costing about 2 to 5 cents per person per year, which makes treating iodine deficiency the most cost-effective way of raising intelligence.
Reducing iodine deficiency can be achieved by adding iodine to salt to form iodized salt. There is a lot of iodized salt in Kenya and many people are unlikely to have this deficiency. However, for areas or countries without, adding iodine to salt is the cheapest and easiest way to fast track IQ gains. It should, however, be noted that healthy individuals who take iodized salt might not benefit from this treatment.
Raising IQs the Flynn Way: Positive Environments
Raising IQ scores does not stop at eradicating negative environments that affect intelligence by hindering brain development. As countries become wealthier, it is possible that negative environmental externalities will be eradicated and more positive environments created. Despite the optimism this far, it’s worth noting that it is not entirely clear what can be done from an environmental perspective to raise IQ scores. One suggestion has been to improve nutrition.
Constance Gewa conducted a randomized longitudinal study for two years where they supplemented the local Githeri eaten by school children in Kyeni, Embu with meat and milk between 1998 and 2000. The goal was to test whether “dietary Fe, Zn and B vitamins (B12, B6, folate and riboflavin)” had any relationships with cognitive gains. The results found that available iron intake was associated with increased IQ gains in fluid intelligence. Increased zinc intake led to higher gains in the digit-span total test scores while vitamin B12 and Riboflavin both showed increased IQ scores in the digit-span forward test. Other than gains in IQ, Charlotte Neumann found that children who ate githeri supplemented with meat “showed near doubling of upper mid arm muscle area, and the milk group a smaller degree of increase.” Schools and governments should look for ways to supplement the diets of children with meat and other important nutrients.
James Flynn is skeptical of IQ gains arising from nutrition and provides an interesting argument. He shows that in countries that have shown significant gains in IQ such as the Netherlands between 1950s and the 1980s, the gains cannot be attributed to nutrition since some of the gains occurred despite the Dutch famine of 1944. He writes that:
The Dutch 18-year-olds of 1962 had a known nutritional handicap. They were either in the womb or born during the great Dutch famine of 1944 when German troops monopolized food and brought sections of the population to near starvation. Yet, they do not show up even as a blip in the pattern of Dutch IQ gains. It appears as if a brief period of food deprivation has little impact if mother and child are well nourished throughout life.(emphasis added)
Flynn also looks at class differences to disprove the idea that nutrition raises IQ. From a class perspective, it is expected that people in the lower classes would benefit more in IQ gains if nutrition was improved. Those on the upper classes can already afford decent food and would otherwise be excluded from these gains. But in countries like the USA between (1948–1989), Netherlands (1952–1982), and France (1949–1974), uniform gains were observed from the lower classes to the upper classes. Diet and improved nutrition was, therefore, not the real drivers of these IQ gains since whatever the poor benefited from the rich too benefited. This is not to mean that famines, starvation, and severe malnutrition have no effect on IQ. They do, especially in countries where these problems are adverse.
Education and Modernity
Flynn places more trust on education and modernity as the real drivers of IQ gains in both the developed and developing countries. He observes that in the last century, increased modernization as countries became wealthier and advanced might have led to the rise of IQ scores.
The ultimate cause of IQ gains is the Industrial Revolution. The intermediate causes are probably its social consequences, such as more formal schooling, more cognitively demanding jobs, cognitively challenging leisure, a better ratio of adults to children, richer interaction between parent and child.(emphasis added)
Modernization as a leading candidate for increasing IQ scores could help solve one difficult problem. Do poor nations have to raise their IQs first before they develop or does development and economic growth come first followed by IQ gains? According to Flynn, modernization raises IQ scores and not the reverse. We can expect that poor nations will modernize first then IQ gains will follow.
Education is also an important contributor to IQ gains even though it is not entirely clear what aspects of education increase IQ scores. Stewart Ritchie shows that an IQ gain of 3.7 points was observed after the Norwegian government decided to add two more years of schooling to its curriculum. Since there is a huge correlation between IQ and the number of years spent in school, it seems the reverse is also true; more years in school might contribute to IQ gains. Flynn on the other hand opines that the observed rise in IQ scores might be a product of increased scientific reasoning among people. People have recently dropped utilitarian lenses and adopted scientific spectacles that make them better at reasoning through IQ tests. He provides the following excerpt from an interview to show how adoption of scientific thinking could change how people approach IQ tests. The individual being interviewed could not clearly tell that the questions required abstract reasoning.
Q: There are no camels in Germany; the city of B is in Germany; are there camels there or not?
A: I don’t know, I have never seen German villages. If B is a large city, there should be camels there.
Q: But what if there aren’t any in all of Germany?
A: If B is a village, there is probably no room for camels.
As Kenya and other African countries develop, modernize, and increase school enrollments, there is a high likelihood that IQs will rise. Through education, many people will don scientific spectacles that will allow them to ditch utilitarian thinking. Modernization and the increased adoption of technologies such as computers and smart phones could also change how people view the world by triggering reasoning patterns commensurate with higher cognitive function. These patterns will further drive the increasing scores even higher. Currently, governments can eradicate negative environments that impair brain development such as lead poisoning and iodine deficiency.
