6.25 : Environmental Influences on Intelligence

Despite the strong genetic influence on traits like intelligence, environmental factors significantly shape outcomes. For example, while over 90% of height variation is due to genetic differences, environmental factors such as nutrition also have a notable impact. Similarly, for intelligence, changes in a child's surroundings can significantly alter their IQ. Research shows that enriched environments boost children's academic success and help them develop key cognitive skills. Children from disadvantaged backgrounds who are adopted into more affluent families often have higher IQs than their biological parents.

Research has consistently shown that early childhood experiences can profoundly influence IQ. The "Database of Raising Intelligence," which regularly compiles studies on various interventions affecting children's intelligence from infancy to age five, supports this claim. Researchers reviewed over 74 studies involving 37,000 children. These studies used controlled experimental designs and demonstrated that interventions could boost childhood IQ.

Critical interventions that positively influence childhood IQ include:

1. Dietary supplements: Supplementing children's diets with long-chain polyunsaturated fatty acids (e.g., Omega-3 fatty acids, found in foods like fish oil and avocados) have increased IQ by more than 3.5 points.
2. Educational interventions: Early educational programs, particularly those targeting complex cognitive tasks, can increase IQ by more than 4 points, especially in disadvantaged children.
3. Interactive reading: Engaging children in active reading sessions, where parents ask questions and encourage discussion, can boost IQ by over 6 points.
4. Preschool: Attending preschool has a significant positive effect, particularly for disadvantaged children, raising IQs by up to 7 points. Programs that focus on language development are particularly effective.