# Energy drink consumption, sleep behavior, and food choices of Icelandic adolescents

**Authors:** Runa Stefansdottir, Arna O. Gunnarsdottir, Bjorn J. Hjalmarsson, Ingibjorg Gunnarsdottir, Erlingur Johannsson

PMC · DOI: 10.29219/fnr.v70.12190 · Food & Nutrition Research · 2026-01-29

## TL;DR

This study finds that Icelandic adolescents who consume energy drinks, especially after 3 PM, tend to sleep less and have poorer diets compared to non-consumers.

## Contribution

The study specifically examines the timing of energy drink consumption and its associations with sleep and dietary habits in Icelandic adolescents.

## Key findings

- 57% of Icelandic adolescents reported energy drink consumption, with higher rates among girls.
- Energy drink consumers slept 6 hours or less, especially when drinking after 3 PM.
- Consumers had poorer diets, with lower intake of nutritious foods and higher intake of soft drinks, coffee, and alcohol.

## Abstract

The consumption of energy drinks has increased in the last decades, especially among adolescents. Caffeine and its effects on sleep are well known, but less is known about the timing of the consumption and its association with sleep and food choices.

The objective of this study was to evaluate the energy drink consumption, sleeping behavior, and food choices in Icelandic adolescents.

A total of 171 participants (64 boys, 107 girls, aged 17–18 years) completed an online questionnaire on sleep, food choices, and energy drink consumption. Independent sample T-tests, Mann-Whitney U tests, and Chi-square tests were used to assess group differences.

Overall, 57% reported drinking energy drinks, with higher rates among girls than boys (63 vs. 48%). Energy drink consumers were more likely to report sleeping 6 h or less. This was especially true for those drinking energy drinks after 3 PM, compared to those who avoided them after 3 PM. Participants who consumed energy drinks also ate fewer nutritious foods (fruits, vegetables, dairy, fish) and consumed more soft drinks, coffee, and alcohol compared to non-energy drink consumers.

The results show that energy drink consumption is frequent among Icelandic 17-year-olds, particularly among girls. Consumers were more likely to report shorter sleep durations, especially when drinking after 3 PM, and had poorer dietary habits, including lower intake of nutritious foods and higher consumption of soft drinks, coffee, and alcohol.

Future research should explore the long-term effects of these behaviors and assess interventions to reduce energy drink use and promote healthier habits in adolescents.

## Linked entities

- **Chemicals:** caffeine (PubChem CID 2519)

## Full-text entities

- **Chemicals:** alcohol (MESH:D000438), Caffeine (MESH:D002110), energy (-)

## Full text

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## Figures

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## References

29 references — full list in the complete paper: https://tomesphere.com/paper/PMC12893045/full.md

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Source: https://tomesphere.com/paper/PMC12893045