Zinc and multivitamin supplementation have contrasting effects on infant iron status: a randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

Zinc supplementation adversely affects iron status in animal and adult human studies but few, trials have included young infants.

OBJECTIVE

To determine the effects of zinc and multivitamin supplementation on infant hematologic and iron status.

METHODS

In a double-blind RCT, Tanzanian infants were randomized to daily, oral zinc (Zn), multivitamins (MV), Zn and MV, or placebo treatment arms at age 6 wk. Hemoglobin concentration (Hb) and red blood cell indices were measured at baseline and at 6, 12, and 18 mo of age. Plasma samples from 589 infants were examined for iron deficiency (ID) at 6 mo.

RESULTS

In logistic regression models, Zn treatment was associated with greater odds of ID (OR 1.8 [95% CI 1.0–3.3]), and MV treatment was associated with lower odds (OR 0.49 [95% CI 0.3–0.9]). In Cox models, MV were associated with a 28% reduction in risk of severe anemia (HR=0.72 [95% Cl 0.56–0.94]) and a 26% reduction in risk of severe microcytic anemia (HR=0.74 [0.56–0.96]) through 18 months. No effects of Zn on risk of anemia were seen. Infants treated with MV alone had higher mean Hb (9.9 g/dL [95% CI 9.7–10.1]) than those given placebo (9.6 g/dL [9.4–9.8]) or Zn alone (9.6 g/dL [9.4–9.7]).

CONCLUSIONS

MV treatment improved iron status in infancy, whereas Zn worsened iron status but without an associated increase in risk for anemia. Infants in long-term zinc supplementation programs at risk for ID may benefit from screening and/or the addition of a multivitamin supplement.

Beyond homogenization discourse: Reconsidering the cultural consequences of globalized medical education

INTRODUCTION

Global medical education standards, largely designed in the West, have been promoted across national boundaries with limited regard for cultural differences. This review aims to identify discourses on cultural globalization in medical education literature from non-Western countries.

METHODS

To explore the diversity of discourses related to globalization and culture in the field of medical education, the authors conducted a critical review of medical education research from non-Western countries published in Academic Medicine, Medical Education and Medical Teacher from 2006 to 2014. Key discourses about globalization and culture emerged from a preliminary analysis of this body of literature. A secondary analysis identified inductive sub-themes.

RESULTS

Homogenization, polarization and hybridization emerged as key themes in the literature. These findings demonstrate the existence of discourses beyond Western-led homogenization and the co-existence of globalization discourses ranging from homogenization to syncretism to resistance.

CONCLUSIONS

This review calls attention to the existence of manifold discourses about globalization and culture in non-Western medical education contexts. In refocusing global medical education processes to avoid Western cultural imperialism, it will also be necessary to avoid the pitfalls of other globalization discourses. Moving beyond existing discourses, researchers and educators should work towards equitable, context-sensitive and locally-driven approaches to global medical education.