Globally, diets are commonly lacking in sufficient zinc for optimum health. Nearly one in five people is estimated to be zinc deficient, which contributes to childhood stunting as well as illness and even death in early life—especially among people living in low-and middle-income countries.
One sustainable way to increase zinc intake is to include zinc-biofortified foods in the diet. However, it has been difficult to determine how added zinc from foods impacts health at the population level. Governments and scientists lack a reliable measure of how the body’s zinc status changes in response to more zinc from food. A good measure is needed to evaluate how well food-based interventions like zinc biofortification work, and thus be able to advocate for their implementation or scaling.
Encouragingly, recent studies have discovered that it is possible to measure how relatively small increases in zinc intake from food (including biofortified food) affect human metabolism, and that food-delivered zinc (rather than zinc supplements between meals) might have a more efficient impact on human metabolism.
A newly published systematic review and meta-analysis of twenty-one studies shows that novel possible biomarkers found in simple blood samples can measure how eating biofortified zinc-enriched foods affects zinc-dependent processes in our body. Biomarkers are objective indicators that accurately and reliably measure the presence or severity of a physiological state in the body, such as body temperature as a biomarker for fever. The potential zinc biomarkers identified in the systematic review are known as FADS1 and FADS2 (fatty acid desaturase 1 and 2), which produce essential health-promoting omega-3 and omega-6 fatty acids.
Since zinc affects the handling of fatty acids to provide energy and produce biologically important structures like cell membranes, measuring the activity of FADS1 and FADS2 offers an indirect way to measure how metabolic processes respond to changes in zinc intake.
“It is inspiring to see that we are making progress in this area of research. Our study provided novel insights on FADS1 and FADS2 activities in relation to zinc intake, clearly indicating research gaps that require additional investigation,” said Marija Knez, lead author of the publication and Nutrition Scientist at the Centre of Research Excellence in Nutrition and Metabolism, Institute of Medical Research, University of Belgrade, Serbia.
While this study raises hopes that FADS1 and FADS2 may become useful tools for measuring the efficacy of zinc biofortified crops and other food-based nutrition interventions, the study authors call for further clinical research to observe the relationships between these biomarkers and zinc intake, and to study other potential biomarkers. This research is a necessary step towards providing decision-makers with a reliable way to take actions towards improving population zinc status.
HarvestPlus, which is a program of the CGIAR, leads a global movement to scale production and consumption of biofortified crops to help address micronutrient deficiency and its many serious health effects on people in low- and middle-income countries. The biofortified crops promoted by HarvestPlus include zinc-biofortified maize, rice, and wheat.
Related research and content:
- FADS1 and FADS2 as biomarkers of Zn status – a systematic review and meta-analysis, Marija Knez, Ana Pantovic, Elad Tako & Erick Boy
- Experts Agree: Zinc Biofortification Holds Promise as a Double Burden Response
- Zinc-Biofortified Wheat Intake and Zinc Status Biomarkers in Men: Randomized Controlled Trial, Erinn M Liong, Christine M McDonald, Jung Suh, Jamie L Westcott, Carmen P Wong, Coralie Signorell, Janet C King