br The main challenges to ensuring

The main challenges to ensuring optimal nutrition of children in low-income and middle-income settings are prevention of undernutrition—including intrauterine growth restriction, stunting, and micronutrient deficiencies—and avoidance of becoming overweight. Birth cohort studies show that linear growth in early life is associated with improved human capital (including intelligence, educational performance, and productivity) and has few, if any, deleterious effects regarding future risk of non-communicable diseases. By contrast, rapid weight gain, above and beyond what is required for linear growth, does not confer any benefits in terms of human capital and is associated with an increased risk of chronic diseases. Early undernutrition followed by exposure to an obesogenic diet in later childhood seems to result in especially poor outcomes. Ensuring that young children achieve optimal linear growth without putting on excessive weight represents a major challenge to public health and nutrition. In 1951, the British nutritionist Isabella Leitch proposed an analogy between the growth of piglets and children. Studying pigs that were undernourished early in life and then fed appropriately, she Oxamflatin cost concluded that “skeleton and muscle will not grow as they would have done if they had had the opportunity at the right time, and the extra food will be used mainly to lay on fat”. She referred to these animals as “low-high” pigs, and proposed they would be better off by remaining thin than by putting on weight, arguing that this condition “can probably be prevented only by the continuation of a spartan regime throughout life, which seems a bit hard”. Whether Leitch\'s ideas were correct and her proposed interventions feasible, she was undoubtedly a pioneer in attempting to translate results from applied animal science to human nutrition. Anyone who has seen or eaten pork for the past few decades will have noticed that today\'s animals have a larger skeletal frame and that their meat has become much leaner over time. This is partly because of breeding, but also because of precise formulation of animal diets. Could new approaches to global nutrition lead to interventions that would make children grow tall without putting on excessive fat, as is the case for present-day piglets? Animal science has been addressing this issue for a long time, although with rigorous studies that cannot be conducted in humans. More than 60 years after Leitch\'s paper, Jack Odle and colleagues produced a landscape review to address a crucial question: what can global human nutrition learn from animal science? The review covered four main areas, known in the global health literature as the continuum of care: preconception, gestation and pregnancy, lactation and suckling, and post-weaning and toddler phases. This review resulted in more than a dozen key findings, suggesting some potential interventions that receive scant attention in global nutrition at present. In particular, the review highlighted “the quantitative importance of essential fatty acid and aminoacid nutrition in reproductive health; the suggested application of the ideal protein concept for improving the aminoacid nutrition of mothers and children; the prospect of using dietary phytase to improve the bioavailability of trace minerals in plant and vegetable-based diets; and nutritional interventions to mitigate environmental enteropathy”. The shows the contrast between Odle and colleagues\' potential recommendations and the comprehensive list of effective diet-related interventions published in the 2013 Nutrition Series (). From the end of World War 2, the global community regarded protein deficiency to be the major nutritional problem in poor countries and called for policies and programmes to close the so-called protein gap. In the mid-1970s, prominent nutritionists declared this to be fallacious using terms such as “the great protein fiasco” and world attention shifted from protein quantity and quality, to quantity of food. More recently, the concern with quality returned but with a focus on micronutrients. The first major difference with respect to animal research is the extent to which human programmes today focus on micronutrients. At different stages during the continuum of care, global nutrition relies on promotion of intake of folic acid, iron, calcium, iodine, vitamin K, vitamin A, and multiple micronutrient supplements. By contrast, animal studies give more comprehensive attention to macronutrients, such as specific aminoacids and fatty acids, which are not considered at all in global human nutrition programmes. Even programmes that promote nutrition counselling with use of locally grown foods or provision of protein-energy supplements do not focus on specific macronutrients. Odle and colleagues emphasise that, in the case of protein and fat, it is crucial to consider both the quantity provided by the diet as well as the pattern of essential aminoacids and fatty acids ingested. They further declare that “the basic information needed to formulate diets to meet aminoacid needs in humans represents a serious gap in knowledge”, unlike animal science where aminoacid patterns resulting in ideal proteins are well described and widely used.