Growing Up in a Greener Environment Boosts Kids’ IQ
Wed, April 21, 2021

Growing Up in a Greener Environment Boosts Kids’ IQ


Greenery in our living environment benefits our health and well-being. It provides spaces for socializing, can encourage exercise, improve immune function by exposure to beneficial microbiota, and decrease air and noise pollution. However, no study has focused yet on intelligence as an outcome of being exposed to green space. This is why a team of researchers from multiple institutions in Belgium conducted a study on residential green space and child intelligence across rural, suburban, and urban areas in Belgium. Children who grow up in a greener environment boosts kids’ intelligence quotient and lowers their levels of difficult behavior, the study has found.

Measuring children’s intellectual ability

Esmée M. Bijnens from the Centre for Environmental Sciences in Hasselt University and the team includes 620 (310 twin pairs) children for their study. These kids were a part of the East Flanders Prospective Twin Survey, which is a registry of multiple births in the province of East Flanders. The children’s intelligence was assessed using the Wechsler Intelligence Scale for Children-Revised (WISC-R). It is an individually administered intelligence test for kids between ages 7 and 15 and generates a full-scale IQ that represents the kid’s general intellectual ability.

Then, from a subset of 442 participants, their behavior was also determined using the Achenbach Child Behavior Checklist (CBCL). It is a checklist used to detect the behavioral and emotional problems in children. Prenatal as well as childhood residential addresses of the participants were geocoded. The authors also used the satellite images of these addresses in assigning green space indicators, which means they will know if the children are living near large lawns, parks, or other greenery.

Residential green space and intelligence and behavior in children

When the authors compared the kids’ proximity to green areas, they found that those who lived in areas with less greenery scored 2.6 points lower, on average, compared to kids who grow up in a greener environment. The team added that the differences in the children’s IQ were not even linked to the economic level. This is because kids in rich areas saw as much decline in green space as those in poor areas in conditions with low green spaces. The decrease of intelligence score was likewise more noticeable among kids who naturally had lower IQs.

A limitation of the study, though, is that no data was available on school location as well as the potential for unmeasured confounding. For instance, the number of times kids spent outdoor was not available, the authors added.

Bijnens and colleagues further compared the kids by their behavioral difficulties linked to short attention spans and aggressiveness. The result shows that kids living in less green spaces scored worse in these areas too. On average, they are two points lower on reports provided by their teachers. The authors could not pinpoint the evidence why a green environment could impact the child’s IQ but the environment likely promotes more social activity and influences reduced stress.

Green space helps children grow up to be happier

Last year, a study, which appeared in the Proceedings of the National Academy of Sciences of the United States of America, also highlight that residential green space in childhood is linked with a lower risk of psychiatric disorders from adolescence into adulthood.

Such a study from Denmark proves that the great outdoors is one of the cheapest therapies for children as they have a 55% less risk of developing various mental disorders later in life. The authors also used satellite data from 1985 to 2013 to map the green space to the participants’ homes. A total of 943,027 Danes was followed from birth to age 10. The longitudinal data on mental health outcomes, place of residents, and socioeconomic status were considered for the study.

Lead researcher Kristine Engemann said that if a person is surrounded by more green space consistently throughout their childhood, they will have an even lower risk of having a psychiatric disorder later on in life. The time they spent outdoors is likewise linked with improved cognition. Engemann added that being in an urban environment is what humans consider stressful. The poor socio-economic conditions, air pollution, and noise can increase the risk of developing a mental disorder.

For kids, if they come back from school and they have a nearby park or have a nice yard at home, it could help restore their mental capacity faster.



Public green space

According to the World Cities Culture Forum, Amsterdam has 13.00% of public green space, which includes parks and gardens. Austin has 11.00%, Barcelona 11.00%, Bogota 4.90%, Brussels 18.80%, Buenos Aires 9.40%, Helsinki 40.00%, Hong Kong 40.00%, Oslo 68.00%, Paris 9.50%, Rome 38.90%, and Seoul 27.80%.

The World Health Organization suggests urban green space interventions as they provide opportunities for an active lifestyle.  These interventions types can be implemented at different scales in public or private spaces, including roadside greenery and vegetation barriers along rail tracks or streets, small urban green spaces, such as pocket parks or gardens, and playgrounds, green roofs, and facades, coastal, riverside, or lakeside trails, linking green with blue spaces, and facilitated access to urban woodlands.



Yale University also provided global metrics for the environment. In 2018, countries with the highest Environmental Performance Index, which means the best countries for green living, include Switzerland (87.42), France (83.95), Denmark (81.60), Malta (80.90), Sweden (80.51), United Kingdom (79.89), Luxembourg (79.12), Austria (78.97), Ireland (78.77), and Finland (78.64).

On the other hand, those with the lowest EPI score includes Burundi (27.43), Bangladesh (29.56), Democratic Republic of Congo (30.41), India (30.57), Nepal (31.44), and Madagascar (33.73). South Korea ranked 60th with a 62.30 EPI score. The report also highlights that quality remains the main environmental threat to public health but the world has also made great strides in protecting terrestrial and marine habitats.

The new findings are beneficial not only to researchers but to urban planners and policymakers as well so they can create an optimal environment for kids to develop their full potential. It can also help parents to choose more nurturing environments for their children. Given a choice, kids naturally want to be outdoors, surrounded by grass, flowers, trees, hearing the wind and the birds, feeling the sunlight and the fresh air, and playing in the water.