Using Stable Isotope Techniques to Assess the Effectiveness of Novel Food-Based Interventions to Enhance Diet Quality in the Context of Changing Food Systems

Food systems are influenced by climate change which has direct impact on nutrition and health. Changes in temperature and rainfall precipitation that can lead to increased (ca 3-84%) global food prices, reduced nutrient value and increased food insecurity. In turn, food insecurity triggers consumption of nutrient-poor and calorie-rich foods and ultimately, hunger and malnutrition (undernourishment, micronutrient deficiencies, overweight and obesity). From a systematic view there is a complex feedback loop in between dietary patterns and environmental impacts throughout the food system. The reduction in nutrient content is contributing to malnutrition, while climate change is affecting biomass, in turn impacting agriculture and biodiversity, resulting in lower crop yields. This creates a cycle of agricultural intensification and increased trade, which further exacerbates climate change. Dietary patterns which promote health typically eliminates dietary practices that increase the risk for all forms of malnutrition and related non-communicable diseases (NCDs). Improved access to whole diets rich in vegetables, fruits, and nuts is likely to be associated with health benefits (such as reduced burden of micronutrient deficiencies and NCDs risk). While the evidence for healthy dietary patterns is driven by NCDs risks, diets should also be nutritionally adequate by providing all the nutrients and dietary energy required to maintain body function. Nevertheless, micronutrient deficiencies persist in LMICs, especially deficiencies of iron, vitamin A, and other micronutrients. Food-based approaches such as diversification of diets including animal source foods, and enhancement of iron intake through supplementation, food fortification and biofortification, are being implemented to address both iron deficiency anaemia and vitamin A status. However, information on the nutritional impact of these approaches is minimal, partly because of limitations in the assessment of iron and vitamin A status and absorption. Hitherto studies to assess micronutrient absorption focus on one micronutrient at a time thereby overlooking potential nutrient-nutrient interactions. Moreover, the studied are mostly cross-sectional in nature, seldom depicting the complexity diet as consumed in long-term free-living settings.  Recent advancements in stable isotope techniques and compartmental mechanistic modelling on both long-term iron and vitamin A bioavailability assessment offers a unique opportunity to better understand biological nuances underpinning the plethora of interacting factors associated with micronutrient absorption. However, this field is still in its nascent stage and needs to be evaluated further. The proposed CRP will delve into the question as to whether these novel approaches could help in building evidence on long-term iron and vitamin A and potentially other nutrients such as B-vitamins absorption from whole diets. It will facilitate improved scientific understanding of key factors that influence bioavailability of micronutrients from whole diets which will improve nutrition security in vulnerable populations affected by disrupted food systems and climate change. The expected outputs will be: 1) stable isotope and mechanistic protocols for assessment of long-term iron and vitamin A bioavailability in complex diets; 2) new data on long-term iron and vitamin A bioavailability from complex diets; 3) new data on interactions between iron and vitamin A and other factors that influence their bioavailability from complex diets; 4) new data on long-term bioavailability of other nutrients such as B-vitamins from complex diets; 5) new data on effect of food-based interventions on long-term iron and vitamin A and other micronutrient bioavailability from complex diets and; 6) publications in the form of scientific reports, peer-reviewed papers and conference abstracts.
 
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