Caitlin J. Andrews’s research while affiliated with The University of Sydney and other places

Transitions to sustainable food systems require shifts in food production and availability, particularly the replacement of animal-based protein with plant-based protein. To explore how this transition may relate to demographic patterns, we undertake an ecological analysis of global associations between age-specific mortality, total national macronutrient distributions, and protein substitution. Our dataset includes per capita daily food supply and demographic data for 101 countries from 1961–2018. After adjusting for time, population size, and economic factors, we find associations between low total protein supplies and higher mortality rates across all age groups. Early-life survivorship improves with higher animal-based protein and fat supplies, while later-life survival improves with increased plant-based protein and lower fat supplies. Here, we show that the optimal balance of protein and fat in national food supplies, which correlates with minimal mortality, varies with age, suggesting that reductions in dietary protein, especially from animal sources, may need to be managed with age-specific redistributions to balance health and environmental benefits.

Multiple sclerosis (MS) is an inflammatory and neurodegenerative disease of the central nervous system (CNS) believed to be driven by autoimmune mechanisms. Genetic and environmental factors are implicated in MS development, and among the latter, diets and nutrients are emerging as potential critical contributors. However, a comprehensive understanding of their impacts and the underlying mechanisms involved is lacking. Harnessing state‐of‐the‐art nutritional geometry analytical methods, it is first revealed that globally, increased carbohydrate supply is associated with increased MS disease burden, while fat supply has an opposite effect. Furthermore, in a MS mouse model, experimental autoimmune encephalomyelitis (EAE), it is found that an isocaloric diet high in carbohydrate aggravated EAE, while a diet enriched in fat (HF) is fully protective. This is reflected by reduced neuroinflammation and skewing toward anti‐inflammatory phenotypes. The protective effects from the HF diet are multifaceted. Metabolically, HF increased lipid storage in immune cells, correlating with their increased anti‐inflammatory IL‐10 production. Transcriptionally and epigenetically, HF feeding preprogrammed naïve T cells toward a less activated but more tolerogenic phenotype. It is showcased that manipulating diets is a potentially efficient and cost‐effective approach to prevent and/or ameliorate EAE. This exhibits translational potentials for prevention/intervention of MS and possibly other autoimmune diseases.

Multiple sclerosis (MS) is a common central nervous system (CNS) autoimmune disease, and diets and nutrients are emerging as critical contributing factors. However, a comprehensive understanding of their impacts and the underlying mechanisms involved is lacking. Harnessing state-of-the-art nutritional geometry analytical methods, we first revealed that globally, increased carbohydrate supply was associated with increased MS disease burden, while fat supply had an opposite effect. Furthermore, in a preclinical MS mouse model, experimental autoimmune encephalomyelitis (EAE), we found that an isocaloric diet high in carbohydrate aggravated EAE, while a diet enriched in fat was fully protective. This was reflected by reduced neuroinflammation and skewing towards anti-inflammatory phenotypes, which involved transcriptomic, epigenetic and immunometabolic changes. We showcased that manipulating diets is a potentially efficient and cost-effective approach to prevent and/or ameliorate EAE. This exhibits translational potentials for intervention/prevention of MS and possibly other autoimmune diseases.