Introduction and objective:
Sleep disorders are now considered to be one of the most common ailments among adults worldwide. There are many factors that can affect sleep disorders, including poor sleep hygiene, chronic stress, the use of stimulants or improper diet. The aim of the study is to investigate the relationship between eating habits and subjective sleep quality assessment in adults.

Material and methods:
The study involved 520 randomly selected Polish adults – 388 women and 132 men. A diagnostic survey method was used in the data collection using a questionnaire consisting of 3 parts: metric, Sleep Quality Assessment Questionnaire and Dietary Quality Assessment Questionnaire.

Results:
Only 29 (8%) of respondents were satisfied with their sleep. The vast majority declared normal sleep quality – 81 (2%). Statistically significant correlations with the sleep quality index occurred only for frequency of consumption of energy drinks (p=0.0051) and sweetened drinks (p=0.0429). As the frequency of consumption of these products increased, the sleep quality index increased, and thus the sleep quality of the subjects deteriorated.

Conclusions:
Nutritional factors, such as irregular meals, low intake of fruit and vegetables, sugary and caffeinecontaining beverages, as well as other lifestyle factors, such as low physical activity and smoking, may also affect sleep quality. Most important is a holistic approach to the problem of insomnia, taking into account a broadly understood lifestyle and sleep hygiene.