Journal Articles

Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915

Browse

Search Results

Now showing 1 - 4 of 4
  • Item
    Evaluation of Protein Adequacy From Plant-Based Dietary Scenarios in Simulation Studies: A Narrative Review
    (Elsevier Inc on behalf of the American Society for Nutrition, 2024-02) Soh BXP; Smith NW; R von Hurst P; McNabb WC
    Although a diet high in plant foods can provide beneficial nutritional outcomes, unbalanced and restrictive plant-based diets may cause nutrient deficiencies. Protein intake from these diets is widely discussed, but the comparison of animal and plant proteins often disregards amino acid composition and digestibility as measurements of protein quality. Poor provision of high-quality protein may result in adverse outcomes, especially for individuals with increased nutrient requirements. Several dietary modeling studies have examined protein adequacy when animal-sourced proteins are replaced with traditional and novel plant proteins, but no review consolidating these findings are available. This narrative review aimed to summarize the approaches of modeling studies for protein intake and protein quality when animal-sourced proteins are replaced with plant foods in diet simulations and examine how these factors vary across age groups. A total of 23 studies using dietary models to predict protein contribution from plant proteins were consolidated and categorized into the following themes-protein intake, protein quality, novel plant-based alternatives, and plant-based diets in special populations. Protein intake from plant-based diet simulations was lower than from diets with animal-sourced foods but met country-specific nutrient requirements. However, protein adequacy from some plant-sourced foods were not met for simulated diets of children and older adults. Reduced amino acid adequacy was observed with increasing intake of plant foods in some scenarios. Protein adequacy was generally dependent on the choice of substitution with legumes, nuts, and seeds providing greater protein intake and quality than cereals. Complete replacement of animal to plant-sourced foods reduced protein adequacy when compared with baseline diets and partial replacements.
  • Item
    Use of the DELTA Model to Understand the Food System and Global Nutrition
    (Oxford University Press on behalf of the American Society for Nutrition, 2021-10) Smith NW; Fletcher AJ; Dave LA; Hill JP; McNabb WC
    BACKGROUND: Increasing attention is being directed at the environmental, social, and economic sustainability of the global food system. However, a key aspect of a sustainable food system should be its ability to deliver nutrition to the global population. Quantifying nutrient adequacy with current tools is challenging. OBJECTIVE: To produce a computational model illustrating the nutrient adequacy of current and proposed global food systems. METHODS: The DELTA Model was constructed using global food commodity balance sheet data, alongside demographic and nutrient requirement data from UN and European Food Safety Authority sources. It also includes nutrient bioavailability considerations for protein, the indispensable amino acids, iron, and zinc, sourced from scientific literature. RESULTS: The DELTA Model calculates global per capita nutrient availability under conditions of equal distribution and identifies areas of nutrient deficiency for various food system scenarios. Modeling the 2018 global food system showed that it supplied insufficient calcium (64% of demographically weighted target intake) and vitamin E (69%), despite supplying sufficient macronutrients. Several future scenarios were modeled, including variations in waste; scaling up current food production for the 2030 global population; plant-based food production systems; and removing sugar crops from the global food system. Each of these scenarios fell short of meeting requirements for multiple nutrients. These results emphasize the need for a balanced approach in the design of future food systems. CONCLUSIONS: Nutrient adequacy must be at the forefront of the sustainable food system debate. The DELTA Model was designed for both experts and nonexperts to inform this debate as to what may be possible, practical, and optimal for our food system. The model results strongly suggest that both plant and animal foods are necessary to achieve global nutrition. The model is freely available for public use so that anyone can explore current and simulated global food systems.
  • Item
    The role of holistic nutritional properties of diets in the assessment of food system and dietary sustainability
    (Taylor and Francis Group, 2023) Dave LA; Hodgkinson SM; Roy NC; Smith NW; McNabb WC
    Advancing sustainable diets for nutrition security and sustainable development necessitates clear nutrition metrics for measuring nutritional quality of diets. Food composition, nutrient requirements, and dietary intake are among the most common nutrition metrics used in the current assessment of sustainable diets. Broadly, most studies in the area classify animal-source foods (ASF) as having a substantially higher environmental footprint in comparison to plant-source foods (PSF). As a result, much of the current dietary advice promulgates diets containing higher proportions of PSF. However, this generalization is misleading since most of these studies do not distinguish between the gross and bioavailable nutrient fractions in mixed human diets. The bioavailability of essential nutrients including β-carotene, vitamin B-12, iron, zinc, calcium, and indispensable amino acids varies greatly across different diets. The failure to consider bioavailability in sustainability measurements undermines the complementary role that ASF play in achieving nutrition security in vulnerable populations. This article critically reviews the scientific evidence on the holistic nutritional quality of diets and identifies methodological problems that exist in the way the nutritional quality of diets is measured. Finally, we discuss the importance of developing nutrient bioavailability as a requisite nutrition metric to contextualize the environmental impacts of different diets.
  • Item
    Hydrogen cross-feeders of the human gastrointestinal tract.
    (Taylor & Francis Group, 2019-01-01) Smith NW; Shorten PR; Altermann EH; Roy NC; McNabb WC
    Hydrogen plays a key role in many microbial metabolic pathways in the human gastrointestinal tract (GIT) that have an impact on human nutrition, health and wellbeing. Hydrogen is produced by many members of the GIT microbiota, and may be subsequently utilized by cross-feeding microbes for growth and in the production of larger molecules. Hydrogenotrophic microbes fall into three functional groups: sulfate-reducing bacteria, methanogenic archaea and acetogenic bacteria, which can convert hydrogen into hydrogen sulfide, methane and acetate, respectively. Despite different energy yields per molecule of hydrogen used between the functional groups, all three can coexist in the human GIT. The factors affecting the numerical balance of hydrogenotrophs in the GIT remain unconfirmed. There is increasing evidence linking both hydrogen sulfide and methane to GIT diseases such as irritable bowel syndrome, and strategies for the mitigation of such health problems through targeting of hydrogenotrophs constitute an important field for further investigation.