# Temporal patterns of total, animal and plant protein intakes of Australian adults: a latent class analysis

## TL;DR

This study identifies three distinct patterns of protein intake timing among Australian adults and links these patterns to age, income, and eating habits.

## Contribution

The study introduces a novel use of latent class analysis to explore temporal patterns of protein intake from different sources.

## Key findings

- Three temporal protein intake patterns were identified, differing by mealtime timing and sociodemographic factors.
- Older adults were more likely to consume protein at typical mealtimes, while younger adults consumed more protein from snacks.
- Income levels were associated with different protein intake patterns, with higher-income individuals showing later mealtime consumption.

## Abstract

Few studies have investigated temporal protein patterns of different protein sources. This study aimed to describe temporal patterns of total, plant, and animal protein intake of Australian adults and examine their associations with sociodemographic and eating pattern characteristics.

Total, animal, and plant protein intakes were estimated from the Australian National Nutrition and Physical Activity Survey 2011–12 dietary recall data (≥ 19 years; n = 6741). Separate latent class models were used to determine the patterns based on hourly intakes of total, animal, and plant protein. Pearson’s Chi-square test and one-way analysis of variance were used to examine the differences in characteristics between latent classes of the patterns.

Three sex-stratified temporal patterns of total (T1-T3), animal (A1-A3), and plant (P1-P3) proteins were identified. Class 1 was characterised by higher probabilities of consuming protein at the typical Australian mealtime (e.g., at 18:00 h for A1), while Class 2 had higher probabilities of intake 1-h later (e.g., 19:00 h for A2). Class 3 was characterised by variable timing (e.g., 17:00 h or 20:00 h for A3). Adults in Class T1, A1, and P1 were older than other classes, whereas those in Class T2 and A2 had higher incomes (all p < 0.001). Adults in Class T3, A3, and P3 were younger and had lower total, animal, and plant protein intakes from meals (all p < 0.001) but higher intakes from snacks (p < 0.001), except for women’s animal protein.

This study identified three temporal protein patterns, which varied by age, income, meal frequency, and protein intake at meals and snacks. Future research needs to examine whether these patterns have different health implications.

The online version contains supplementary material available at 10.1007/s00394-026-03918-8.