# Assessing Plant-Based Diets in Taiwan Using a Harmonized Food Description-Incorporated Framework

## TL;DR

This study uses a new food classification system to assess plant-based diets in Taiwan and finds age-related differences in diet quality and BMI.

## Contribution

The paper introduces a harmonized framework for classifying plant-based diets and applies it to evaluate dietary patterns in Taiwan.

## Key findings

- Older adults (46–70 years) had higher healthy plant-based diet scores and better nutrient-rich food indices.
- Higher healthy plant-based diet tertiles were associated with lower BMI despite overall higher average BMI in the population.
- The proposed system supports scalable and standardized analysis of plant-based diets for cross-national research.

## Abstract

Background: Exploring emerging dietary patterns, such as plant-based diets (PBD), often requires considerable effort to rebuild new systems or adapt existing food classification frameworks, presenting a substantial challenge for dietary research. Current systems were not originally designed for this purpose and vary in standardization and interoperability, complicating cross-study comparisons. This study aimed to adopt the harmonized, food description-incorporated, food classification system (HFDFC system) to develop a plant-based diet food classification system (PBDFC system), and to evaluate dietary intake and nutritional status among adults in Taiwan. Methods: A repeated cross-sectional design was applied using 24 h dietary recall data from the Nutrition and Health Survey in Taiwan (2013–2016 and 2017–2020), accessed via the national food consumption database. Adults aged 20–70 years were included. Data were processed through the HFDFC system to generate the PBDFC system. For each participant, the Plant-Based Diet Index (PDI), Body Mass Index (BMI), and Nutrient-Rich Food Index (NRF) were calculated and analyzed by age group. Results: Adults aged 46–70 had significantly higher O-PDI and H-PDI scores, lower Lh-PDI scores (all p < 0.0001), and higher NRF values. Despite higher average BMI, those in the highest H-PDI tertile had significantly lower BMI (p < 0.02). Conclusions: The HFDFC-based PBDFC system offers a flexible, scalable framework for plant-based diet classification and supports future cross-national research.