Measuring intellect

The Database of Raising Intelligence is a collection of controlled studies that were designed to increase intelligence in people of all ages. The database includes only those trials of high methodological quality that use standardized measures of intelligence to assess the outcomes.

Sixty-three studies that looked at children from the prenatal period through age five years met the criteria for inclusion in a recent addition to the database. These studies focused on the effects of nutritional supplements and environmental changes on children's intelligence.

Be smart about fat

DHA (docosahexaenoic acid) is a fatty acid that aids in brain and neurological development. Breast milk is naturally high in DHA, along with other health-promoting substances. Several studies support the use of DHA supplements during pregnancy and lactation to help boost babies' levels of this nutrient.

• The database found that supplementing pregnant mothers' diets or infant formula with DHA raises a young child's IQ by more than 3.5 points.

Get early intervention

Early educational intervention programs are intended to enrich young children's lives before they reach preschool age. The database included those studies that accomplished this through home visits, parent training, special child development centers, or some combination of these.

• Enrolling children in intense early educational interventions can raise their IQ in early childhood.
• More complex interventions tend to lead to greater IQ gains.

"We found no evidence to support the notion that interventions conducted earlier in young childhood more effectively boost IQ than those that begin later," commented the authors.

Read like you mean it

Several studies have looked at how training programs designed to help parents read effectively with their children might help boost intelligence. These programs teach parents how to ask open-ended questions, encourage their children to read, and follow their children's lead about their interests.

• The database concluded that reading to a child in an interactive style raises IQ by more than 6 points.
• Children younger than four-years-old seem to benefit most from this interactive reading style.

Sign them up for preschool

The database included 16 studies that looked at the effect of going to preschool on IQ in over 7,000 young children.

• Attending preschool may raise children's IQ by more than 4 points.
• Children who attend preschools that include a specific language development component may get an IQ boost of more than 7 points.

The early educational intervention trials, interactive reading studies, and preschool studies only included children from lower socioeconomic classes, so the results from these can't necessarily be generalized to children from all income classes.

"Our current findings strengthen earlier conclusions (for example, that complex environments build intelligence), cast doubt on others (for example, that earlier interventions are always most effective), and give rise to tantalizing new questions for future research," concluded the researchers.

(Perspect Psychol Sci 2013;DOI:10.1177/1745691612462585)