Adherence to the Mediterranean Diet and Its Association With Sleep Quality and Chronotype Among Youth: A Cross-Sectional Study

Associations of dietary patterns with objective and subjective sleep duration and sleep quality in a population-based cohort study

OBJECTIVE

To examine cross-sectional and longitudinal associations of various types of dietary patterns with self-reported sleep quality and with actigraphy-estimated sleep parameters in the prospective, population-based Rotterdam Study.

METHODS

For each participant, scores for five different dietary patterns were derived based on food frequency questionnaires; two pre-defined scores developed to estimate adherence to the Dutch dietary guidelines and to the Mediterranean diet; and three data-driven scores indicating a prudent, unhealthy and typical Dutch diet. In 2589 participants (median age 56.9 years; 58 % female), self-rated sleep quality was assessed with the Pittsburgh Sleep Quality Index. In 533 participants, actigraphs were worn for an average of 6.8 days (SD: 0.7) to estimate total sleep time, sleep onset latency, wake after sleep onset, and sleep efficiency. Sleep parameters were measured at baseline and 3-6 years later. Multiple linear regression was used to assess cross-sectional and longitudinal associations.

RESULTS

No statistically significant associations between dietary patterns and total sleep time, sleep onset latency, wake after sleep onset, sleep efficiency and subjective sleep quality were observed in cross-sectional or longitudinal analyses. To illustrate, the effect estimate for sleep duration was 2.7 min per night (95 % CI -2.1, 7.5) per 5 point increase in Mediterranean diet score in the cross-sectional analyses. Furthermore, in longitudinal analyses, the effect estimate for sleep duration was -1.0 min per night (95 % CI -5.2, 3.1) per SD increase in the prudent diet.

CONCLUSIONS

Our results suggest that dietary patterns are not associated with sleep in this population-based cohort study.

TRIAL REGISTRATION

Netherlands National Trial Register and WHO International Clinical Trials Registry Platform (ICTRP; https://apps.who.int/trialsearch/) shared catalogue number NL6645/NTR6831. Registered November 13th, 2017.

The relationship between chronotype and food addiction: Serial mediation of social jetlag and psychological pain

This study evaluates how food addiction is related to chronotype, social jetlag, and psychological pain. Of the participants (n = 1,035 university students), 16.6% had a morning chronotype, 25.1% had an evening chronotype, and 25.1% were clinically addicted to eating. The mean sleep durations for participants were 7.41 ± 2.18 h and 8.95 ± 3.0 h on weekdays and weekends, respectively. The mean misalignment time for social jetlag was 1.45 ± 1.5 h. Food addiction, psychological pain, and social jetlag levels were high among participants with the evening chronotype. The risk factors for food addiction included being female, having an evening chronotype, and having high body mass index levels and psychological pain. The total indirect effect of psychological pain and social jetlag on the relationship between chronotype and food addiction was 20.6%. However, the social jetlag effect is relatively minor compared to psychological pain. The significant conclusions of this study are as follows. Clinical food addiction is prevalent among students, and a strong direct correlation between chronotype and food addiction was observed. The study emphasizes the importance of being aware of chronotype and mental status in establishing a healthy diet and lifestyle.

Mediterranean diet adherence and sleep pattern: a systematic review of observational studies

BACKGROUND AND AIMS

Despite a huge body of evidence on the linkage between dietary intakes and pattern of sleeping, the findings are controversial. The current study aimed to summarize earlier findings on the association between adherence to Mediterranean diet (MD) and pattern of sleeping.

METHODS

This study performed based on PRISMA guideline. Systematically search was applied in PubMed, Scopus and Google Scholar to find out relevant publications appeared up to February 2023. No restrictions on language and time of publication were applied. Duplicate citations were removed. We included observational studies which assessed MD as the main exposure and kind of sleep disorders as the main outcome.

RESULTS

A total of 20 observational studies included. Out of these studies, two were cohort studies and 18 had a cross-sectional design. A total of 21,714 participants included. Usual dietary intakes were assessed using a validated Food Frequency Questionnaire, and a diet history questionnaire. Some studies did not report methods of measuring habitual dietary intakes. Adherence to MD was evaluated by KIDMED questionnaire, PREMED, alternate Mediterranean (aMed) questionnaire, MEDAS questionnaire, MedDietScore, MEDI-LITE score, modified Mediterranean Diet Score (mMDS), Mediterranean food pattern (MFP) and modified Mediterranean diet score (mMED). Pattern of sleeping was examined as sleep quality, sleep duration, sleep latency, sleep efficacy, sleepiness, sleep disturbance, taking a nap and some other sleep disorders.

CONCLUSION

In conclusion, findings of published studies highlighted the importance of consumption of MD for better sleep quality.

Association of Mediterranean diet with sleep quality, depression, anxiety, stress, and body mass index in university students: A cross-sectional study

Background: The Mediterranean diet (MD) has many beneficial effects on health. However, compliance with MD is decreasing among university students. Aim: This study aims to investigate compliance with the MD and the association of MD with sleep quality, depression, anxiety, stress, and body mass index (BMI) among university students. Methods: This cross-sectional study included 750 students of Ondokuz Mayıs University, a state university in Samsun, Türkiye. Sociodemographic data and self-reported anthropometric data (weight and height) were recorded using a survey. The Mediterranean diet quality index for children and adolescents (KIDMED), the Pittsburgh sleep quality index (PSQI), and the depression anxiety stress scale-42 (DASS-42) were self-administered. Results: Most students (59.2%) had poor KIDMED adherence. Compared to poor adherers, those with good adherence to the KIDMED had significantly lower depression scores (in males and females). Higher adherence to the KIDMED was correlated with lower depression and stress levels (in males and females) and lower PSQI scores (lower sleep disturbances) in females. The KIDMED scores of overweight females were greater than those of underweight females. Conclusion: University students show poor adherence to the MD. Low adherence to the MD may have a negative impact on depression, stress, and sleep quality. This study suggests that interventions to promote MD may help improve university students' sleep disturbances and mental health.

Changes in dietary and lifestyle behaviors and mental stress among medical students upon Ramadan diurnal intermittent fasting: a prospective cohort study from Taif/Saudi Arabia

BACKGROUND

Intermittent fasting (IF) is a popular dietary plan for weight loss. In fact, fasting is a common practice in different religions such as Buddhism, Hinduism, Judaism, Christianity, and Islam. During the month of Ramadan, more than 1.5 billion Muslims worldwide fast from dawn to sunset. Ramadan diurnal intermittent fasting (RDIF) has health benefits, including a reduction in cardiovascular disease (CVD) risk and an improvement in mood. However, little is known about the effects of RDIF on lifestyle behaviors, such as regular exercise, consuming healthy diet, and avoiding harmful substances, as well as mental stress, and academic performance in high school and university students.

METHODS

In this prospective cohort study, two self-reported questionnaires were sent one week before and during the last week of Ramadan (April 2022; Ramadan 1443 in Hijri Islamic Calendar) to assess changes in lifestyle, perceived stress, and academic achievement of medical students at Taif University in Taif city, Saudi Arabia. Healthy lifestyle components data were collected to calculate healthy lifestyle scores, including body mass index, physical activity, adherence to a Mediterranean diet, smoking status, and sleep duration.

RESULTS

RDIF was associated with a healthier lifestyle in both female and male participants (pre-RDIF mean score: 2.42 vs post-RDIF mean score: 2.74; statistical power = 0.99; P-value < 0.05). They were more active and adherent to the Mediterranean diet during RDIF. Additionally, the post-RDIF smoking rate declined by 53.4%. Male participants showed higher perceived stress scores during RDIF (pre-RDIF mean score: 19.52 vs post-RDIF mean score: 22.05; P-value < 0.01). No changes in academic performance were observed upon RDIF.

CONCLUSION

Medical students show healthier dietary and lifestyle behaviors and their academic performance is not affected during RDIF. However, perceived stress is higher among male students.

Impact of Chronotype and Mediterranean Diet on the Risk of Liver Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease

Late chronotype, the individual's aptitude to perform daily activities late in the day, has been associated with low adherence to the Mediterranean diet (MedDiet) and metabolic syndrome. The aim of this work was to investigate the potential association of chronotype and adherence to the MedDiet with the liver fibrosis risk in patients with non-alcoholic fatty liver disease (NAFLD). Liver stiffness was assessed in 126 patients by FibroScan^®530. Significant (F ≥ 2) and advanced (F ≥ 3) hepatic fibrosis were defined according to liver stiffness values ≥7.1 kPa and ≥8.8 kPa, respectively. Chronotype (MSFsc) was defined by the Munich Chronotype Questionnaire, and adherence to the MedDiet was defined by the Mediterranean diet score (MDS). Overall, the median age was 55 (46-63) years, and 57.9% of participants were male. The principal comorbidities were type-2 diabetes mellitus (T2DM) (26.1%), arterial hypertension (53.1%), dyslipidaemia (63.4%), obstructive sleep apnoea (5.5%) and depression (5.5%). Most subjects (65.0%) had intermediate + late chronotype and showed higher mid-sleep on workdays (p < 0.001) and on work-free days (p < 0.001) compared to those with early chronotype. In the logistic regression model, intermediate + late chronotype (p = 0.024), MDS (p = 0.019) and T2DM (p = 0.004) were found to be significantly and independently associated with the risk of both F ≥ 2 And F ≥ 3. We observed that the intermediate + late chronotype and low adherence to the MedDiet were associated with both significant and advanced liver fibrosis in patients with NAFLD.

Identification of dietary compounds that interact with the circadian clock machinery: Molecular docking and structural similarity analysis

The molecular clock is vital for regulating circadian rhythms in various physiological processes, and its dysregulation is associated with multiple diseases. As such, the use of small molecule modulators to regulate the molecular clock presents a promising therapeutic approach. In this study, we generated a homology model of the human circadian locomotor output cycles kaput (CLOCK) protein to evaluate its ligand binding sites. Using molecular docking, we obtained further insights into the binding mode of the control compound CLK8 and explored a selection of dietary compounds. Our investigation of dietary compounds was guided by their potential interactions with the retinoic acid-related orphan receptors RORα/γ, which are involved in circadian regulation. Through the molecular similarity and docking analyses, we identified oleanolic acid demethyl, 3-epi-lupeol, and taraxasterol as potential ROR-interacting compounds. These compounds may exert therapeutic effects through their modulation of RORα/γ activity and subsequently influence the molecular clock. Overall, our study highlights the potential of small molecule modulators in regulating the molecular clock and the importance of exploring dietary compounds as a source of such modulators. Our findings also provide insights into the binding mechanisms of CLK8 and shed light on potential compounds that can interact with RORs to regulate the molecular clock. Future investigations could focus on validating the efficacy of these compounds in modulating the molecular clock and their potential use as therapeutic agents.

Mediterranean Diet Adherence Is Associated with Favorable Health-Related Quality of Life, Physical Activity, and Sleep Quality in a Community-Dwelling Greek Older Population

BACKGROUND

The Mediterranean diet (MD) is a beneficial dietary pattern with strong antioxidant and anti-inflammatory properties that can promote mental and physical human health. This study aims to assess the impact of MD adherence on health-related quality of life, physical activity levels, and sleep quality in a representative Greek elderly population.

METHODS

This is a cross-sectional study. A total of 3254 persons ≥65 years from 14 different Greek regions, urban, rural and islands participated in this study, of which 48.4% were female and 51.6% were male. Health-Related Quality of Life (HRQOL) was evaluated utilizing a short form healthy survey, physical activity was determined by the International Physical Activity Questionnaire (IPAQ), sleep quality was assessed utilizing the Pittsburgh Sleep Quality Index (PSQI) and MD adherence was assessed via the Mediterranean Diet Score (MedDietScore).

RESULTS

Moderate adherence to the MD and an increased prevalence of poor quality of life, low physical activity levels and inadequate sleep quality among the elderly population were recorded. High MD adherence was independently associated with better quality of life (OR: 2.31, 95% CI: 2.06-2.68, p = 0.0008), higher physical activity (OR: 1.89, 95% CI: 1.47-2.35, p = 0.0141) and adequate sleep quality (OR: 2.11, 95%: 1.79-2.44, p = 0.0018), female sex (OR: 1.36, 95% CI: 1.02-1.68, p = 0.0032) and living with others (OR: 1.24, 95% CI: 0.81-1.76, p = 0.0375), after adjustment for potential confounding factors. In unadjusted analysis, participants' age (p < 0.0001), anthropometric characteristics (p < 0.005), educational (p = 0.0026) and financial status (p = 0.0005) and smoking habits (p = 0.0031) were also identified as indicators of MD adherence; however, their impact on MD adherence was considerably attenuated after adjusting for confounding factors (p > 0.05).

CONCLUSION

High MD adherence was correlated with favorable quality of life, higher levels of physical activity, and a more adequate sleep quality score. Strategies and public health policies that facilitate MD adherence and physical activity in older adults may improve sleep and quality of life, impacting overall wellbeing in this age group.

Examination of sleep in relation to dietary and lifestyle behaviors during Ramadan: A multi-national study using structural equation modeling among 24,500 adults amid COVID-19

Background

Of around 2 billion Muslims worldwide, approximately 1.5 billion observe Ramadan fasting (RF) month. Those that observe RF have diverse cultural, ethnic, social, and economic backgrounds and are distributed over a wide geographical area. Sleep is known to be significantly altered during the month of Ramadan, which has a profound impact on human health. Moreover, sleep is closely connected to dietary and lifestyle behaviors.

Methods

This cross-sectional study collected data using a structured, self-administered electronic questionnaire that was translated into 13 languages and disseminated to Muslim populations across 27 countries. The questionnaire assessed dietary and lifestyle factors as independent variables, and three sleep parameters (quality, duration, and disturbance) as dependent variables. We performed structural equation modeling (SEM) to examine how dietary and lifestyle factors affected these sleep parameters.

Results

In total, 24,541 adults were enrolled in this study. SEM analysis revealed that during RF, optimum sleep duration (7-9 h) was significantly associated with sufficient physical activity (PA) and consuming plant-based proteins. In addition, smoking was significantly associated with greater sleep disturbance and lower sleep quality. Participants that consumed vegetables, fruits, dates, and plant-based proteins reported better sleep quality. Infrequent consumption of delivered food and infrequent screen time were also associated with better sleep quality. Conflicting results were found regarding the impact of dining at home versus dining out on the three sleep parameters.

Conclusion

Increasing the intake of fruits, vegetables, and plant-based proteins are important factors that could help improve healthy sleep for those observing RF. In addition, regular PA and avoiding smoking may contribute to improving sleep during RF.

Nutritional Elements in Sleep

Sleep comprises one-third of our day and plays an integral role in human health and well-being. Many factors influence sleep, with nutrition being a key element that impacts various sleep parameters. Meal-timing through strategies like chrono-nutrition leads to positive sleep outcomes. In addition, consuming a high-protein diet with essential amino acids, low-glycemic-index foods, and certain fruits rich in antioxidants can all contribute to better sleep quality. Other facets of nutrition that can affect sleep outcomes include weight loss and limiting certain nutritional elements such as caffeine, nicotine, and alcohol. In this article, we will shed some light on how some of these factors can play a vital role in sleep quality.

Good Adherence to the Mediterranean Diet Lowered Risk of Renal Glomerular Impairment in Children: A Longitudinal Study

Healthy diet patterns have a positive effect on chronic non-communicable diseases in the pediatric population, but the evidence is limited on the association between kidney impairment and adherence to a Mediterranean diet. We aim to determine the associations between Mediterranean diet adherence and longitudinal tubular and glomerular impairment in children. Based on four waves of urine assays conducted from October 2018 to November 2019, we assayed urinary β₂-microglobulin (β₂-MG) and microalbumin (MA) excretion to determine transient renal tubular and glomerular impairment during the follow-up of the child cohort (PROC) study in Beijing, China. We assessed Mediterranean diet adherence using the 16-item Mediterranean Diet Quality Index in children and adolescents (KIDMED) among 1914 primary school children. Poor, intermediate, and good adherence rates for the Mediterranean diet were 9.0% (KIDMED index 0–3), 54.4% (KIDMED index 4–7) and 36.5% (KIDMED index 8–12), respectively. A short sleep duration was more prevalent in children with lower Mediterranean diet adherence, with no significant differences presenting in the other demographic and lifestyle covariates. The results of linear mixed-effects models showed that a higher urinary MA excretion was inversely associated with a higher KIDMED score (β = −0.216, 95%CI: −0.358, −0.074, p = 0.003), after adjusting for sex, age, BMI z-score, SBP z-score, screen time, sleep duration and physical activity. Furthermore, in generalized linear mixed-effects models, consistent results found that transient renal glomerular impairment was less likely to develop in children with intermediate Mediterranean diet adherence (aOR = 0.68, 95%CI: 0.47, 0.99, p = 0.044) and in children with good Mediterranean diet adherence (aOR = 0.60, 95%CI: 0.40, 0.90, p = 0.014), taking poor Mediterranean diet adherence as a reference. We visualized the longitudinal associations between each item of the KIDMED test and kidney impairment via a forest plot and identified the main protective eating behaviors. Children who adhere well to the Mediterranean diet have a lower risk of transient glomerular impairment, underscoring the necessity of the early childhood development of healthy eating patterns to protect kidney health.

Mediterranean Diet on Sleep: A Health Alliance

The Mediterranean diet is a plant-based, antioxidant-rich, unsaturated fat dietary pattern that has been consistently associated with lower rates of noncommunicable diseases and total mortality, so that it is considered one of the healthiest dietary patterns. Clinical trials and mechanistic studies have demonstrated that the Mediterranean diet and its peculiar foods and nutrients exert beneficial effects against inflammation, oxidative stress, dysmetabolism, vascular dysfunction, adiposity, senescence, cognitive decline, neurodegeneration, and tumorigenesis, thus preventing age-associated chronic diseases and improving wellbeing and health. Nocturnal sleep is an essential physiological function, whose alteration is associated with health outcomes and chronic diseases. Scientific evidence suggests that diet and sleep are related in a bidirectional relationship, and the understanding of this association is important given their role in disease prevention. In this review, we surveyed the literature concerning the current state of evidence from epidemiological studies on the impact of the Mediterranean diet on nighttime sleep quantity and quality. The available studies indicate that greater adherence to the Mediterranean diet is associated with adequate sleep duration and with several indicators of better sleep quality. Potential mechanisms mediating the effect of the Mediterranean diet and its foods and nutrients on sleep are described, and gap-in-knowledge and new research agenda to corroborate findings are discussed.

Comparative Study Regarding the Adherence to the Mediterranean Diet Among Older Adults Living in Lebanon and Syria

The Mediterranean diet (MedDiet) has been associated with many health benefits. Poor adherence to MedDiet has been found among Lebanese adults, while in Syria, little is known about the adherence to MedDiet. A quantitative research approach was used, and data were collected through convenience sampling. The structure of the survey included the socio-economic and demographic data and the validated 14-point MedDiet assessment tool. The target population included 367 Lebanese and Syrian adults respectively residing in Lebanon and Syria. Descriptive statistics were used to explore the characteristics of the sample population. Adequate adherence MedDiet was determined if the Med-Diet score ≥ 9. Significant differences among the variables and the adherence to the MedDiet were examined using the chi-square test. Approximately 47.42% of participants reported adherence to MedDiet higher than 9, with a mean of 7.98. Lebanese participants, men, and those who are aged between 64 and 67, had higher adherence than Syrian participants, women, and other age groups, respectively. Lebanese participants (7.82 ± 2.32) had slightly higher adherence than Syrian participants (7.31 ± 2.04). Wine, sofrito, vegetables, and olive oil were mostly consumed by participants, with differences in consumption between the Lebanese and Syrian adults. The statistical analysis performed using the chi-square test showed no statistical difference (P&gt;.05) between Lebanese and Syrian participants regarding their consumption of 160 red meat, butter/margarine, and sugary drinks. Future studies in the aged population are required to explore furthermore the adherence to MedDiet in Lebanon and Syria and its impact on health.