Introduction
Some studies are available on the alarming rate of overweight and
obesity among college students1-4. The majority of
college students do not regard the dietary and physical activity
guidelines, indicating the necessity of prevention treatments and
increased understanding of overweight in college
students2. In
addition to the high prevalence of overweight and obesity among college
students, lack of sleep quality is also a prevalent occurrence among
this population which has affected 10% to 50% of this
population5,6 lack of sleep quality have profound
effects on students’ health (including increased risk of chronic
diseases), quality of life, mood, and daytime
function7,8. Lack of sleep quality similar to obesity,
is associated with increased circulatory levels of pro-inflammatory
markers and consequent insulin resistance and orexin
decline9. Orexin is essential for the stability of
sleep/wake states in various species, namely dog, mouse, and
human10. Orexin knockout mice have exhibited frequent
sudden collapses during the dark phase, the portion of the circadian
rhythm during which there is the most time awake and spent in the
activity. These attacks resemble human cataplexy
attacks11. Orexin neuron activity is suppressed by
Tumor Necrosis Factor- alpha (TNF-α) through this cytokine degrading the
mRNA of orexin precursor in a time- and dose-dependent
manner12,13.
Observational studies showed an independent association between the lack
of sleep quality and elevated high-sensitivity C-Reactive Protein
(hs-CRP), but this relationship was gender-specific in some
studies14-17. Vgontzas and colleagues found that two
hours of sleep reduction per night for seven nights led to increased
TNF-α in healthy men but not women, but increased Interleukin 6 (IL-6)
in both men and women18. In sum, sleep restriction
leads to a systemic increase of the inflammatory mediators that may have
prognostic significance for metabolic diseases.
Literature has supported diet represents an essential role in the
modification and regulation of low-grade chronic
inflammation19,20. So, it has been confirmed that
Western dietary patterns have pro-inflammatory potential, and contrarily
healthy dietary patterns such as the Mediterranean diet are related to
anti-inflammatory status21. Dietary patterns have been
shown to influence inflammatory pathways; for instance, adherence to
healthy dietary patterns such as the Mediterranean diet and/or national
dietary guidelines can decrease inflammation and the
Mets22.An umbrella meta-analysis of studies found
promising evidence about the significant benefits of the Mediterranean
diet in lowering body weight, Body Mass Index (BMI) and Waist
Circumference (WC) as well as the improvement of lipid profile versus
the control diets4. Okun et al. showed that young and
healthy women with a poor sleep had more circulatory levels of
C-Reactive Protein (CRP) compared to women with better sleep quality.
The authors supposed that this pro-inflammatory status may increase the
risk of various diseases that affect women, such as polycystic ovary
syndrome and preeclampsia. However, they couldn’t find any significant
association between sleep duration and inflammatory
markers23. The results of the National Health and
Nutrition Examination Survey of (NHANES) 2005-2006 among 2051 adults
(≥20 years) indicated that having regular physical activity and not
smoking and healthy eating and enough sleep were the two health behavior
pairs related to lower systemic inflammation24. In
this regard, the Dietary Inflammatory Index (DII®) was
designed to assess the inflammatory potentials of the individuals ‘diet.
It was proven that this index could predict inflammation-related health
status in any population25. Two review studies
concluded that the DII score appears to be a beneficial tool to assess
the dietary inflammatory capacity and to perceive further the
correlations between diet, inflammation, and chronic metabolic diseases
such as obesity, diabetes, and Cardiovascular Diseases
(CVD)26-28.
Overweight, obesity and lack of sleep quality as inflammatory states are
the common problems among college students and the association of DII
with these problems among this population is unknown28. It was hypothesized that a diet with a higher
inflammatory potential could be associated with obesity and poor sleep
in Iranian female students.