The Effect of Breastfeeding on Intelligence Quotient and Social Intelligence Among Seven- to Nine-Year-Old Girls: A Pilot Study

Abstract

Background: Breastfeeding is an optimal infant feeding method that provides adequate nutrients, achieves healthy growth and development, and enhances the health status of both infants and mothers. Breast milk contains a variety of substances that might positively affect cognition and the development of children's psychomotor abilities.

Objective: This study aimed to examine the variations in intelligence quotient (IQ), social intelligence (SI), and body mass index (BMI) among 7- to 9-year-old girls who were exclusively breastfed, exclusively bottle-fed, or mixed-fed during their first 6 months of life.

Methods: This study involved 111 healthy girls, aged 7 to 9 years, who were recruited from nine government and private schools in Dammam, Kingdom of Saudi Arabia. Raven's Coloured Progressive Matrices were used to measure the participants' IQs, and the Vineland Social Maturity Assessment was used to measure their SI through individual interviews. Anthropometric measurements were obtained using standard methods.

Results: The breastfed group showed a greater number of above-average IQ test scores (35 vs. 23%; P = 0.479) and better SI scores (78 vs. 55%; P = 0.066) compared with the bottle-fed group. The number of girls with normal BMIs was significantly higher in the breastfed group than in the bottle-fed (68 vs. 41%; P = 0.045) or mixed-fed groups.

Conclusion: Exclusively breastfed girls had higher IQ and SI results compared with bottle-fed girls. However, unlike the BMI differences, these results were not statistically significant. This study provides fundamental observational data and can be further modified for use on a larger national-scale level.

Keywords: Saudi Arabia; body mass index; bottle-feeding; breastfeeding; intelligence quotient (IQ); social intelligence.

Figure 1

Flowchart of participant selection.

Figure 2

Intelligence quotient (IQ) levels among breastfed, bottle-fed, and mixed-fed groups.

Figure 3

Social intelligence (SI) levels among the three feeding groups. Higher SI levels (>140) were seen more often in the breastfed group (78%) than in the other groups, and the lowest SI levels were noted in the bottle-fed group (in 5% of group participants). No low SI scores were noted in the other two groups.

Figure 4

Body mass index (BMI) categories among the three feeding groups. The BMI measures were normal, more often in the breastfed group (68%) than in other groups (e.g., 41% in the bottle-fed group), and more obese BMI levels were seen in the bottle-fed group than in other groups (P = 0.435).