Nutritional status of primary school children: Association with intelligence quotient and academic performance

Nutrition plays a pivotal role in brain development throughout life. Sub-optimal intellectual ability and poor school performance are said to be among the long term effects of malnutrition. The aim of this study was to determine the association between nutritional status of the participants, their intelligence quotient (IQ) and academic performance.

Children aged 6-12 years who met the inclusion criteria were recruited from the public and private primary schools in the local government area using a proportionate multistage sampling technique. Weight and height were measured using standard protocols and interpreted as normal or abnormal using the World Health Organization AnthroPlus®. IQ was assessed using the Raven's Standard Progressive Matrices and was grouped into optimal and suboptimal. Academic performance was assessed using the past records of class assessment, and was classified into high, average and low academic performance. A semi-structured questionnaire was used to obtain data such as-age, gender, socioeconomic indices and family size of the study participants.

The prevalence of underweight, thinness (wasting), stunting, overweight and obesity were 2.0%, 3.6%, 2.1%, 6.7%, and 4.2%, respectively. Indices of over-nutrition were significantly associated with optimal IQ and good academic performance. There was a trend in the association between wasting and suboptimal intelligence [AOR (95%CI) = 1.5 (1.0-3.0), p = 0.06].

Acute and chronic under-nutrition did not adversely affect the IQ and academic performance of the study population. The relationship between over-nutrition, IQ and academic performance disappeared when socio-economic status was controlled for.