When modeling shapes the message: Interpreting vegetarian and vegan dietary patterns in the dietary guidelines for Americans.

Abstract

The 2025-2030 Dietary Guidelines for Americans include vegetarian and vegan dietary patterns as potential options for meeting nutrient needs across the lifespan, while also identifying several nutrients of potential concern within these patterns. These conclusions have important implications for dietetic practice, public communication, and policy development. However, estimates of nutrient adequacy derived from food pattern modeling are inherently shaped by the assumptions used to construct dietary scenarios, including decisions related to food substitution, energy balance, and the treatment of fortification and supplementation. This article provides a balanced examination of the strengths and limitations of the current modeling framework as applied to vegetarian and vegan dietary patterns. The protective intent of the conservative approach and its value for public health guidance are outlined, alongside alternative analytical strategies that address complementary questions regarding nutrient source composition under fixed energy conditions.