Recommended sleep duration is associated with higher consumption of fruits and vegetables; cross-sectional and prospective analyses from the UK Women’s Cohort Study

The Association Between Diets With High Inflammatory Potential and Sleep Quality and Its Parameters: A Systematic Review

CONTEXT

Dietary components or its overall properties can influence an individual's sleep status.

OBJECTIVE

The aim for this study was to critically search, appraise, and synthesize research evidence on the association between dietary inflammatory index (DII) and sleep quality and its parameters.

DATA SOURCES

Original published studies on adults were obtained from the PubMed, SCOPUS, ScienceDirect, Cochrane Library, and Google Scholar databases.

DATA EXTRACTION

The search was conducted without date limitation until April 2023. Duplicated and irrelevant investigations were screened out, and the results of the remaining articles were descriptively summarized, then critically appraised and analyzed. Possible mechanistic pathways regarding diet, systemic inflammation, and sleep status were discussed.

DATA ANALYSIS

Of the 102 studies searched, 23 articles (n = 4 cohort studies, 18 cross-sectional studies, and 1 intervention study) were included in the final review. The association between DII and sleep status was investigated subjectively in 21 studies and objectively in 6 studies. The main studied sleep outcomes were sleep quality, duration, latency, efficiency, apnea, disturbances, the use of sleeping medications, daytime dysfunctions, wakefulness after sleep onset, and rapid eye movement.

CONCLUSIONS

According to most of the evidence, DII may not be related to overall sleep quality, sleep duration, latency, efficiency, and the use of sleeping medications. The evidence of positive association was greater between a high DII score (pro-inflammatory diet) with daytime dysfunctions, wakefulness after sleep onset, and sleep apnea. There is insufficient evidence to make any conclusion regarding sleep disturbances and rapid eye movement.

Consumption of fruits and vegetables and its association with sleep duration among Finnish adult population: a nationwide cross-sectional study

Introduction

Sleep and diet are crucial determinants of overall health and wellbeing, with the potential to mutually influence each other. This study examined the association between sleep duration and fruits and vegetables (FV) consumption among Finnish adults.

Methods

The study analyzed data from the National FinHealth 2017 Study involving 5,043 adults aged 18 years and above. Participants reported their habitual sleep duration, and dietary consumption through a validated self-administered questionnaire. Confounders such as demographic, socio-economic factors, and chronotype were considered. A sensitivity analysis, which excluded energy under-reporters, was conducted to validate the findings.

Results

Mean dietary consumption was compared across three sleep duration categories (short, normal, long), revealing that short sleepers consumed 37 g/d fewer FV, and long sleepers consumed 73 g/d fewer FV than normal sleepers. Binary logistic regression analyses consistently demonstrated significant negative association between FV consumption and both short and long sleep duration across all models, even when adjusted for a range of covariates. Linear regression analyses revealed a positive but non-significant association between sleep duration and FV consumption that became significant when excluding energy under-reporters, particularly in model 1.

Discussion

This study suggests a consistent pattern where deviation from normal sleep duration was associated with decreased FV consumption, suggesting the need for considering sleep patterns in dietary intervention. The substantial role of accurate energy reporting in explaining these associations is highlighted. Further research, including longitudinal studies, is needed to better understand the mechanisms underlying these associations.

Personality, dietary identity, mental and sleep health in vegans and vegetarians: A preliminary cross-sectional study

Background and Aims

Plant-based diets have gained popularity over the past decade. However, research regarding mental and sleep health benefits of following plant-based diets are conflicting. As there are associations between mental/sleep health and various personality traits, and personality may differ between individuals who follow different diets, in this preliminary study, we examined the associations between mental and sleep health and (i) personality and (ii) dietary identity in individuals who follow vegan and vegetarian diets.

Methods

Cross-sectional data on sociodemographic, personality traits, dietarian identity, overall mental health, depression, anxiety, stress, and sleep quality were collected from 57 vegan/vegetarian participants between the ages of 18-40.

Results

After controlling for various sociodemographic and lifestyle factors, linear regression models revealed that (i) higher dietarian private regard was a significant predictor of better overall mental health, (ii) lower levels of extraversion and higher levels of empathy predicted depression, (iii) higher levels of neuroticism and empathy predicted anxiety, (iv) higher levels of neuroticism, dietarian centrality, and neuroticism × centrality predicted stress, (v) higher levels of conscientiousness, lower levels of dietarian centrality, but higher levels of personal motivation and dietary strictness, as well as conscientiousness × centrality, conscientiousness × personal motivation, and conscientiousness × strictness predicted better sleep quality.

Conclusions

These preliminary findings suggest that not only personality traits, but also dietary identity was indeed related to mental and sleep health in individuals who follow plant-based diets.

The Relationship Between Dietary Intake and Sleep Quality in Endurance Athletes

Many endurance athletes have poor sleep quality which may affect performance and health. It is unclear how dietary intake affects sleep quality among athletes. We examined if sleep quality in endurance athletes is associated with consumption of fruit, vegetables, whole grains, dairy milk, and caffeinated beverages. Two hundred thirty-four endurance athletes (39.5 ± 14.1 year) participated in a survey. Participants provided information on demographics, anthropometry, sleep behavior and quality, and dietary intake via questionnaires. Sleep quality was assessed using the Athlete Sleep Screening Questionnaire (ASSQ) with a global score (ASSQ-global) and subscales including sleep difficulty (ASSQ-SD), chronotype (ASSQ-C), and disordered breathing while sleeping (ASSQ-SDB). A general linear model (GLM), adjusted for age, body mass index, sleep discomfort, sleep behavior, gender, race, and ethnicity, showed that higher caffeinated beverage intake was related to poorer global sleep quality (p = 0.01) and increased risk for disordered breathing while sleeping (p = 0.03). Higher whole grain intake was associated with a morning chronotype and lower risk for sleep issues (p = 0.01). The GLM did not reveal a relationship between sleep quality and dairy milk, fruit, and vegetable intake. In conclusion, caffeinated beverages and whole grain intake may influence sleep quality. This relationship needs to be confirmed by further research.

Improvement Predictors in a Workplace Program Promoting Healthy Lifestyle Habits

BACKGROUND

The baseline characteristics of employees to predict improvements in healthy lifestyle habits (LHs) following workplace health promotion programs are underexplored. This study sought to identify predictors of improvements in physical activity (PA), eating habits, sleep habits, and stress management, and health risk factors resulting from healthy LHs.

METHODS

The Activate Your Health program included 3 packages of an increasing number of interventions: light, moderate, and high. Participating employees (n = 506) completed baseline and postintervention questionnaires that collected sociodemographic data, health- and LH-related variables, stress-related variables, and perceptions of general health and life satisfaction. Only those with the potential to improve were included in each improvement outcome analysis.

RESULTS

Being in high and intending to reduce alcohol consumption increased the odds of improving PA. Very good/excellent perceived general health, poor sleep habits, high alcohol consumption, and intending to improve stress management increased the odds of improving stress levels at work. Depression and intending to improve sleep habits increased the odds of improving stress management. Reporting feelings of pleasure increased the odds of improving body mass index.

CONCLUSIONS

Baseline characteristics predicting improvements differed for each LH. A targeted approach may be needed to help employees improve LHs and related outcomes.

Is adherence to the Mediterranean diet associated with good sleep duration in primary-school children?

OBJECTIVE

The Mediterranean diet (MD) contributes to preventing numerous chronic diseases and has benefits on cognitive development. Adherence to the MD is associated with sleep quality and duration in adults and adolescents, but this association seems to have been little investigated in primary-school children. The aim of this cross-sectional study was to verify whether good sleep duration was associated with adherence to the MD.

DESIGN

The study enrolled a sample of Italian primary school children. Their mothers were asked to answer an anonymous, self-administered questionnaire investigating the children's adherence to the MD (using the KidMed score) and variables related to their lifestyles, behavioral traits and socio-economic factors. Logistic regression models were developed to analyze the association between adherence to the MD, entered as the dependent variable, and adequacy of sleep duration.

SETTING

Primary schools in Padova, Italy.

SUBJECTS

267 Italian 6-year-olds in their first year of primary school.

RESULTS

The multivariate analysis showed an association between adherence to the MD and hours of sleep: for children with a good sleep duration, the odds ratio of a poor-to-moderate adherence to the MD was 0.282 (95% CI, 0.109-0.681, p < 0.05).

CONCLUSION

Ensuring an adequate sleep duration may be an important strategy for enhancing adherence to the MD. Sleep and dietary education should be included in future health promotion programs.

Anxiety symptoms and mild cognitive impairment among community-dwelling older adults from low- and middle-income countries

AIM

Anxiety may be a risk factor for mild cognitive impairment (MCI) but there is a scarcity of data on this association especially from low- and middle-income countries (LMICs). Thus, we investigated the association between anxiety and MCI among older adults residing in six LMICs (China, Ghana, India, Mexico, Russia, South Africa), and the mediational effect of sleep problems in this association.

METHODS

Cross-sectional, community-based, nationally representative data from the WHO Study on global AGEing and adult health (SAGE) were analyzed. The definition of MCI was based on the National Institute on Ageing-Alzheimer's Association criteria. Multivariable logistic regression analysis, meta-analysis, and mediation analysis were conducted to assess associations.

RESULTS

The final sample included 32,715 individuals aged ≥50 years with preservation in functional abilities [mean (standard deviation) age 62.1 (15.6) years; 48.3% males]. Country-wise analysis showed a positive association between anxiety and MCI in all countries (OR 1.35-14.33). The pooled estimate based on meta-analysis with random effects was OR=2.27 (95%CI=1.35-3.83). Sleep problems explained 41.1% of this association.

CONCLUSIONS

Older adults with anxiety had higher odds for MCI in LMICs. Future studies should examine whether preventing anxiety or addressing anxiety among individuals with MCI can lead to lower risk for dementia onset in LMICs, while the role of sleep problems in this association should be investigated in detail.

Diet, Sleep, and Mental Health: Insights from the UK Biobank Study

Diet has long been the focus of attention as a leading risk factor for non-communicable diseases. As such, a better understanding of it is crucial to establish priorities for dietary guidelines and to inform, design, and implement strategies for preventing, helping manage, and stopping the progression of sleep and mental health-related symptoms/disorders. The aim of the current study is to conduct the largest investigation of diet, sleep, and mental health to date by utilizing the UK Biobank (UKB) dataset to identify the associations between diet and (i) sleep quality/health, and (ii) mental health symptomatology. This cross-sectional population-based study involved 502,494 middle-aged adults. UKB food frequency, sleep, and psychological factors and mental health questionnaires at baseline were used. Scores were also calculated for healthy diet, healthy sleep, mental health symptomatology, partial fibre intake, and milk intake. We observed positive associations with healthy diet and sleep and mental health, especially benefits of high intakes of vegetable, fruit, fish, water, and fibre. However, processed meat and milk intake were adversely associated with sleep and mental health. These findings make clear that there are health and wellbeing benefits and drawbacks of different diets, but do not, at this stage, demonstrate the clear causal relationships, which would support dietary interventions that might play a role in the treatment and also self-management of sleep and mental health disorders/symptoms. Further research is required to understand mechanisms of actions of which diet acts on to modulate sleep and mental health, while taking comorbidity of sleep and mental health disorders/symptoms into consideration.

Habitual Sleep Duration, Daytime Napping, and Dietary Intake: A Mendelian Randomization Study

BACKGROUND

Chronic inadequate sleep and frequent daytime napping may inflict deleterious health effects including weight gain, cardiometabolic and psychiatric diseases, and cancer. It is plausible that these relations may be partly influenced by the consumption of suboptimal diets.

OBJECTIVES

The study aimed to identify potential causal links of genetically proxied longer habitual sleep duration and more frequent daytime napping on 61 dietary variables derived from an FFQ. In addition, the study aimed to assess potential bidirectional causal links between habitual sleep duration or daytime napping and macronutrient composition.

METHODS

Genetic variants robustly associated with habitual sleep duration and daytime napping from published genome-wide association analyses were used. Outcomes included 61 dietary variables estimated from FFQs in the UK Biobank (n = 361,194). For bidirectional associations with macronutrient composition, genetic variants associated with percentage of energy from carbohydrate, fat, and protein were used. Two-sample Mendelian randomization (MR) effects were estimated with inverse-variance weighted (IVW) analysis.

RESULTS

In 2-sample MR, genetically proxied longer sleep duration was associated with a 0.068 (95% CI: 0.034, 0.103) category increase in salad/raw vegetable intake [P false discovery rate (FDR) = 0.006] per hour of sleep and with "no major dietary changes in the past 5 years" (P FDR = 0.043). No associations were evident for daytime napping on dietary variables (all P FDR > 0.05). In addition, there were no bidirectional associations between habitual sleep duration or daytime napping with the relative intake of carbohydrate, fat, and protein (all P IVW > 0.05).

CONCLUSIONS

In this MR study, there was modest evidence for associations between habitual sleep duration with dietary intake and no evidence for associations between daytime napping frequency with dietary intake. These preliminary findings suggest that changes to habitual sleep duration or daytime napping frequency may have limited impact on long-term changes in dietary intake.

Exploring Relationships of Sleep Duration with Eating and Physical Activity Behaviors among Canadian University Students

BACKGROUND

Students pursuing postsecondary education are a population described as vulnerable for sleep problems, poor dietary habits, weight gain, and reduced physical activity. The primary goal of this study was to examine relationships of sleep behaviors with eating and physical activity behaviors in a sample of undergraduate health sciences students.

METHODS

Using a cross-sectional design, undergraduate health sciences students in a small Canadian university were recruited to complete an on-line questionnaire about their sleep, eating, and physical activity behaviors using valid and reliable instruments. Key sociodemographic characteristics and self-reported height and weight data were also captured.

RESULTS

The participants (n = 245) were on average 23 years of age, female (86%), and the majority were full-time students (92%). The mean BMI was within a healthy range (mean 24.58 SD 5.55) with the majority reporting low physical activity levels (65%). Despite self-reports of very or fairly good (65%) sleep quality in the past month, the mean global sleep scores (scores > 5, mean 7.4, SD 3.3) indicated poor overall sleep quality. Poorer sleep quality was associated with higher BMIs (r = 0.265, p < 0.001).

CONCLUSIONS

The findings highlight the need to expand the scope of on-campus wellness programs to promote healthy sleep habits in a vulnerable university population.

Bridging the Reciprocal Gap between Sleep and Fruit and Vegetable Consumption: A Review of the Evidence, Potential Mechanisms, Implications, and Directions for Future Work

A substantial burden of disease and mortality globally is attributable to both sleep disruption and low intakes of fruit and vegetable (FV) and there is increasing mechanistic and epidemiological evidence to support a reciprocal relationship between the two. This review provides an overview of experimental and observational studies assessing the relations between sleep and FV consumption from 52 human adult studies. Experimental studies are currently limited and show inconsistent results. Observational studies support a non-linear association with adults sleeping the recommended 7–9 hours/day having the highest intakes of FV. The potential mechanisms linking sleep and FV consumption are highlighted. Disrupted sleep influences FV consumption through homeostatic and non-homeostatic mechanisms. Conversely, FV consumption may influence sleep through polyphenol content via several potential pathways. Few human experimental studies have examined the effects of FV items and their polyphenols on sleep and there is a need for more studies to address this. An appreciation of the relationship between sleep and FV consumption may help optimize sleep and FV consumption and may reduce the burden of chronic diseases. This review provides implications for public health and directions for future work.