A dream diet? Voedingskwaliteit en slaap in de algemene bevolking en in mensen die gediagnostiseerd en behandeld zijn voor chronische ziekten: observationeel onderzoek en interventie studies.

Sleep is important for our health and quality of life. A dietary pattern with a high diet quality is increasingly explored for its potential benefits on sleep outcomes. This thesis examined if diet quality affected sleep outcomes in the general population and in people diagnosed with and treated for chronic diseases using observational data and intervention studies. We observed no associations between dietary patterns and both objective and subjective sleep outcomes among a population-based sample. Furthermore, we concluded that small but realistic improvements in diet quality after dietary counselling or lifestyle coaching, do not seem to have an effect on sleep outcomes among patients with established cardiovascular diseases, among patients with type 2 diabetes mellitus, and among survivors of colorectal cancer. Null findings, such as the findings in this thesis, are important to balance studies that promote easy solutions for sleep disturbances that might be “too good to be true”.