# Examining the non-linear relationship between sugar consumption and anxiety symptoms in UK biobank data

## TL;DR

This study finds a non-linear link between sugar consumption and anxiety symptoms, with patterns varying by gender and age.

## Contribution

The novel contribution is identifying specific non-linear thresholds and patterns of sugar types affecting anxiety across different demographics.

## Key findings

- Non-linear associations between sugar consumption and GAD scores were found, modified by gender and age.
- Sucrose showed a J-shaped pattern in both genders, particularly significant in females aged 65 or older.
- Total sugar and sucrose had notable non-linear effects in younger and middle-aged groups.

## Abstract

Generalized anxiety disorder (GAD) is a common psychiatric condition. The role of sugar in emotional health is becoming more apparent. This cross-sectional study investigated the potential non-linear associations of sugar on GAD and identified thresholds that would be associated with GAD if these non-linear associations were significant, using the UK Biobank.

A sample of 84,087 subjects was included. Total energy and sugar consumption were calculated using Oxford WebQ. Total sugar, glucose, fructose, maltose, and sucrose as dietary exposure. The Generalized Anxiety Disorder-7 (GAD-7) questionnaire was used to measure anxiety symptoms. The non-linear relationship between sugar and GAD scores was examined using generalized additive models (GAMs).

Significant non-linear relationships were found between sugar consumption and GAD score, and were modified by gender and age. Total sugar and sucrose consumption demonstrated non-linear associations with GAD scores among those aged 45 or younger. In those aged 46 to 64 years, non-linear associations of GAD score were found in total sugar consumption in both genders. Additionally, in females, non-linear associations were also observed across all the sugar types; compared to males, only sucrose consumption showed a significant association. Specifically, the association between sucrose consumption and GAD score followed a J-shaped pattern in both genders. Only sucrose consumption demonstrated a non-linear association with GAD scores in females aged 65 or above.

This study identified non-linear and dose-dependent associations between various types of sugar on anxiety in different gender and age groups, which may have implications for lifestyle psychiatry.

The online version contains supplementary material available at 10.1186/s12937-025-01277-4.