The Journal of Nutrition Community and International Nutrition Some Indicators of Nutritional Status Are Associated with Activity and Exploration in Infants at Risk for Vitamin and Mineral Deficiencies 1–4 Nancy J. Aburto, 5,6 * Manuel Ramirez-Zea, 7 Lynnette M. Neufeld, 7 and Rafael Flores-Ayala 5 5 Division of Nutrition, Physical Activity and Obesity, CDC, Atlanta, GA 30341; 6 Nutrition and Health Research Center, National Institute of Public Health, Cuernavaca 62100, Mexico; and 7 Institute of Nutrition of Central America and Panama, Guatemala City, Guatemala 01011 Abstract Severe malnutrition, both protein-energy and micronutrient deficiency, results in decreased activity, but the results regarding mild-to-moderate malnutrition are equivocal. Our objective in this investigation was to describe the activity and exploratory behavior of Mexican infants and describe the relationship among nutritional status, activity, and exploration in this population at high risk for mild-to-moderate micronutrient deficiency, but at low risk for severe malnutrition. The participants were infants, 4–12 mo old, of low socioeconomic status from 3 states in southern Mexico. We measured anthropometrics using standard techniques. We measured hemoglobin (Hb) concentration in the field and adjusted values for altitude before analysis. We measured activity and exploration by direct observation during 15 min of individual play in a novel environment. Cluster analysis generated mutually exclusive activity clusters and exploration clusters based on patterns of bodily movement and exploratory behavior, respectively. We categorized the clusters as higher or lower activity or higher or lower exploration. A higher Hb concentration and height-for-age Z-score (HAZ) significantly increased the odds of being in the high-activity cluster. Iron deficiency, stunting, and wasting significantly decreased the odds of being in the high-activity cluster. Higher HAZ and weight-for-age Z-score significantly increased the odds of being in a higher exploration cluster. In Mexican infants at risk for mild-to-moderate micronutrient deficiency but at low risk of severe malnutrition, some indicators of nutritional status were related to increased activity and exploration. J. Nutr. 139: 1751– 1757, 2009. Introduction Both acute and chronic severe protein-energy malnutrition result in decreased physical activity in children (1–3) that can be reversed with nutritional supplementation (4–6). There is also evidence that mild-to-moderate protein-energy malnutrition can reduce activity (7–10), but the evidence is equivocal (11,12). A number of animal and human studies have reported that micronutrient deficiencies, especially of iron and zinc, also result in reduced activity levels (13–20). Most evidence suggests that poor nutritional status is related to reduced exploration of the environment, which could have adverse developmental consequences (21,22). In Jamaica, stunted infants had less enthusiasm and variety in exploration than did nonstunted infants (21). In Bangladeshi infants, iron and zinc supplementation for 6 mo improved orientation- engagement scores, a test of exploration, and improved arousal, positive affect, and fearlessness compared to controls (23). A study of Indonesian infants who were moderately protein-energy malnourished reported that energy and iron supplementation increased time separated from the mother, one definition of exploratory behavior, compared with controls (24); however, the same study also reported that supplementation reduced object manipulation, another definition of exploratory behavior (25). Some research suggests that reduced activity results in reduced exploration. Studies from Jamaica and Guatemala reported a reduction in physical activity simultaneous to a reduction in exploration in malnourished compared to well-nourished chil- dren; however, neither study had the a priori objective of examining the relationship between activity and exploration (2,4). Definitive conclusions regarding the relationship among 1 The Mexican Secretary of Social Development, represented by the Human Development Program, Oportunidades financed the data collection for this study as part of the Oportunidades impact evaluation. The design, analysis, interpretation of the findings and manuscript writing were the sole responsibility of the authors. 2 Author disclosures: N. J. Aburto, M. Ramirez-Zea, L. M. Neufeld, and R. Flores-Ayala, no conflicts of interest. 3 The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the CDC. 4 Supplemental Methods for measuring physical activity and exploration are available with the online posting of this paper at jn.nutrition.org. * To whom correspondence should be addressed. E-mail: gdi9@cdc.gov. 0022-3166/08 $8.00 ã 2009 American Society for Nutrition. Manuscript received October 2, 2008. Initial review completed November 9, 2008. Revision accepted July 2, 2009. 1751 First published online July 29, 2009; doi:10.3945/jn.108.100487. Downloaded from https://academic.oup.com/jn/article/139/9/1751/4670540 by guest on 10 July 2023