# Timing of Dietary Fatty Acids to Optimize Reduced Risk of Type 2 Diabetes Mellitus: Findings from China Health and Nutrition Survey

## TL;DR

Eating certain healthy fats like n-3 PUFAs and plant-based MUFAs at dinner instead of breakfast may help reduce the risk of type 2 diabetes.

## Contribution

This study identifies the timing of specific dietary fatty acid intake as a novel factor in type 2 diabetes prevention.

## Key findings

- Higher intake of n-3 PUFAs and plant-based MUFAs at dinner was linked to a reduced T2DM risk.
- Switching fatty acid intake from breakfast to dinner lowered T2DM risk by 20-22%.
- Associations were stronger for dinner versus breakfast than for lunch versus breakfast.

## Abstract

Background/Objectives: Chrononutrition highlights the significance of temporal consumption behavior for a healthy dietary pattern. This study investigated the relationship between dietary fatty acid (FA) intake timing and type 2 diabetes mellitus (T2DM) risk. Methods: A total of 14,518 participants in the China Health and Nutrition Survey (1991–2015) were recruited. Dietary intake and mealtime were collected via three consecutive 24 h dietary recalls. Multivariable Cox proportional hazard models were employed to estimate the association between FA intake at meals and T2DM risk. Differences in FA intake between dinner and breakfast (Δ = dinner-breakfast) were calculated for each type of FA intake. Sensitivity analyses considering the effects of snacks, the sum of different types of FAs, and other confounding factors were performed. The isocaloric substitution model was used to view the risk changes according to the shifted mealtime. Results: During an average of 10.1-year follow-up, 1048 T2DM cases occurred. T2DM risk was inversely associated with n-3 polyunsaturated FAs (n-3 PUFAs) (p trend = 0.032) and plant-sourced monounsaturated FAs (P-MUFAs) (p trend = 0.002) intake at dinner versus breakfast. The highest category of Δ n-3 PUFAs and Δ P-MUFAs were respectively linked to a 19% and 29% reduced T2DM risk. Unanimous associations were found for the difference between lunch and breakfast rather than dinner and lunch. Isocalorically switching 1 standard deviation (SD) of n-3 PUFAs or MUFAs intake at breakfast with the corresponding type of FAs at dinner was associated with a 22% and 20% lower risk of T2DM, respectively. Conclusions: Timely consumption of dietary FAs, particularly n-3 PUFAs and plant-based MUFAs at dinner versus breakfast, is crucial for T2DM prevention.