Conclusions of the Joint WHO/UNICEF/IAEA/IZiNCG Interagency Meeting on Zinc Status Indicators

Abstract

Zinc deficiency is an important cause of morbidity in developing countries, particularly among young children, yet little information is available on the global prevalence of zinc deficiency. A working group meeting was convened by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF), the International Atomic Energy Agency (IAEA), and the International Zinc Nutrition Consultative Group (IZiNCG) to review methods of assessing population zinc status and provide standard recommendations for the use of specific biochemical, dietary, and functional indicators of zinc status in populations. The recommended biochemical indicator is the prevalence of serum zinc concentration less than the age/sex/time of day-specific cutoffs; when the prevalence is greater than 20%, intervention to improve zinc status is recommended. For dietary indicators, the prevalence (or probability) of zinc intakes below the appropriate estimated average requirement (EAR) should be used, as determined from quantitative dietary intake assessments. Where the prevalence of inadequate intakes of zinc is greater than 25%, the risk of zinc deficiency is considered to be elevated. Previous studies indicate that stunted children respond to zinc supplementation with increased growth. When the prevalence of low height-for-age is 20% or more, the prevalence of zinc deficiency may also be elevated. Ideally, all three types of indicators would be used together to obtain the best estimate of the risk of zinc deficiency in a population and to identify specific subgroups with elevated risk. These recommended indicators should be applied for national assessment of zinc status and to indicate the need for zinc interventions. The prevalence of low serum zinc and inadequate zinc intakes may be used to evaluate their impact on the target population's zinc status.

Micronutrient intake and status in Central and Eastern Europe compared with other European countries, results from the EURRECA network

“…3. Regarding nutritional status, data gathered should include information on mean or median status using best practice biomarkers defined in the context of EURRECA: Hb, serum/plasma ferritin or serum/plasma transferrin receptor for Fe; erythrocyte (red cell) folate, serum/plasma folate or serum/plasma homocysteine for folate; serum/plasma total B 12 , serum/plasma methylmalonic acid or serum/plasma holotranscobalamin for vitamin B 12 ; serum/plasma Zn for Zn; and urinary iodine (24 h or spot), serum or dried whole blood spot thyroglobulin or serum thyroid-stimulating hormone for iodine (20)(21)(22)(23)(24)(25)(26)(27) .…”

“…To assess adequacy of levels of status markers, we used guidance on cut-off values from EURRECA experts (30)(31)(32)(33) . These cut-off values were based on key references mostly published by the WHO in cooperation with other institutions (20)(21)(22)(23)(24)(25)(26)(27) .…”

Determinantes dietéticos del consumo de zinc en menores de cinco años con retardo de crecimiento en comunidades mayas de Guatemala

“…En Guatemala, esta alcanza 34,9% e, incluso, 46,7% en algunas regiones (4) , zonas que también presentan prevalencias elevadas de RC (5) . Con base en el indicador "riesgo de deficiencia de zinc" propuesto por Wessells (6) , el cual integra la prevalencia estimada de consumo inadecuado de zinc y la de RC, Guatemala es uno de los países con mayor riesgo de deficiencia en Latinoamérica (7) .…”

“Hartnell's time machine” reprise: Further implications of zinc, lead and copper in the thumbnail of a Franklin expedition crewmember

“…First, healthy subjects are reported with lower levels of nail zinc than Hartnell (İlhan et al, 2004). Secondly, the WHO endorses serum or plasma zinc as a biomarker of the metal (de Benoist et al, 2007), a standard that is supported by a systematic review which concludes that there are insufficient studies of several potential biomarkers, including nail, to determine whether they reflect zinc status (Lowe et al, 2009). Thirdly, Wieringa et al (2015 observe that there is no specific biomarker related to zinc deficiency per se, being consistent with the WHO's observation that whilst serum and plasma zinc are biomarkers of the metal they do not necessarily reflect the individual's zinc status.…”