A Systematic Review of the Bidirectional Association Between Consumption of Ultra-processed Food and Sleep Parameters Among Adults.
Level 4 - case-series / case-control
Systematic review of cross-sectional observational studies.
PubMed 37477854 · doi:10.1007/s13679-023-00512-5
What was done
MEDLINE and EMBASE were searched through April 2023 for epidemiological studies evaluating bidirectional associations between ultra-processed food (UPF; NOVA Group 4) intake and sleep parameters in general adult populations. Fifteen cross-sectional studies met inclusion criteria. Thirteen studies examined UPF intake as an exposure (using food frequency questionnaires in 73% and 24-h recalls in 27%) and two examined sleep as an exposure. Sleep was evaluated using accelerometry in 2 studies and self-reports in the rest, with 60% using a single question.
What was found
Six of 13 studies examining UPF intake as the exposure reported inverse associations with sleep outcomes in adjusted (n = 5) or bivariate (n = 1) analyses. Both studies testing sleep as the exposure found significant inverse associations with UPF consumption. The average study quality was judged as fair. No aggregate effect sizes or numerical risk estimates were reported in the abstract.
Why it matters
This review highlights an emerging link between ultra-processed food consumption and compromised sleep parameters, while mapping substantial methodological gaps in current nutritional epidemiology.
Limits
All included studies were cross-sectional, ruling out causal inference. Sleep measurement was predominantly crude and subjective, with 60% of studies relying on a single question and only two using accelerometry. Dietary intake assessments relied on self-report questionnaires subject to recall bias.