Modeling the Impact of Substituting Meat and Dairy Products with Plant-Based Alternatives on Nutrient Adequacy and Diet Quality.

ABSTRACT

BACKGROUND: Novel plant-based meat and dairy alternatives are designed to mimic and replace animal-sourced products, yet their nutritional composition differs from traditional alternatives such as legumes and beans. The nutritional impacts of switching from animal-sourced to traditional or novel plant-based alternatives remains unclear. OBJECTIVES: This study aimed to model the impact of partial and complete substitution of animal-sourced meat and dairy products with traditional or novel plant-based alternatives on diet quality and nutrient adequacy in a nationally representative sample of Australian adults. METHODS: Dietary data (1 24-h recall) from the Australian Health Survey 2011-2013 (n = 9115; ≥19 y) were analyzed. Four models simulated partial or complete substitution of animal-sourced meat and dairy with traditional or novel plant-based alternatives. Diet quality was assessed using the Dietary Guideline Index (DGI), and nutrient adequacy was determined using age- and sex-specific nutrient reference values. Modeled diets were compared to a baseline diet using survey-weighted paired t tests. RESULTS: DGI scores improved by 0.3% to 6.0% for all models across all sex and age groups compared to baseline. Improvements in diet quality were greatest for the complete substitution to traditional alternatives (5.1% average increase in DGI). Overall, inclusion of plant-based alternatives (complete or partial) decreased saturated fat and increased dietary fiber. Long-chain n-3 polyunsaturated fatty acids decreased to below adequate intakes for all complete substitution models. Substitution with traditional alternatives decreased sodium and increased calcium, whereas substitution with novel alternatives increased sodium and decreased calcium. CONCLUSIONS: All models using traditional alternatives, and the partial substitution using novel alternatives, showed small but statistically significant improvements in diet quality. Nutrient adequacy varied between models, with nutrients including saturated fat, sodium, calcium, and long-chain fatty acids implicated. Findings highlight the importance of informed choices when switching to traditional or novel plant-based alternatives to prevent suboptimal dietary intake.