Relationships among dietary nutrients and subjective sleep, objective sleep, and napping in women

Effect of Peanut Butter Intake on Sleep Health in Firefighters: A Randomized Controlled Trial

Sleep is often impaired in firefighters due to the psychologically and physiologically intense nature of their work and working shift schedules. Peanut butter is affordable and a substantial source of monounsaturated fatty acids, which may aid sleep health. Thus, this study sought to determine if a daily serving of peanut butter consumed before bedtime for seven weeks altered sleep quality and quantity among full-time firefighters. Forty firefighters (peanut butter group = 20; control group = 20) participated in this eight-week randomized controlled trial. All participants completed a subjective questionnaire on mood, focus, and alertness twice daily and wore an Actigraph wristwatch to measure sleep variables, including latency, efficiency, time in bed, time asleep, wake after sleep onset, number of awakenings, and time spent awake. After a baseline week, the peanut butter group consumed two tablespoons of peanut butter two hours prior to bedtime for seven weeks. Compared to the control group, the peanut butter group did not demonstrate significant changes (p > 0.05) in sleep measures or subjective feelings of mood, focus, or alertness after consuming peanut butter for seven weeks. Therefore, peanut butter as a source of peanuts did not alter sleep quality or quantity in this group of firefighters.

Assessing the daily association of sleep hygiene behaviours with sleep: A between and within persons approach

Sleep hygiene behaviours are recommendations given to both clinical and non-clinical populations with a focus on modifying behaviours to maximise sleep outcomes. However, methodological issues present in sleep hygiene research make it difficult to conclusively determine the impact of each behaviour. This study aimed to address these issues by adopting a two-week, repeated measures design which incorporated objective sleep measures and used linear mixed effect modelling to assess the daily association of a wide range of sleep hygiene behaviours on sleep in a non-clinical, university sample. Between-persons effects revealed that bedtime and frequency of daytime napping, alcohol use, and social media use were negatively related to sleep duration while waketime and frequency of too much water consumption were positively related to sleep duration. Within-person effects revealed that later than usual bedtime, earlier than usual waketime, no sunlight exposure, poor ventilation, having an unpleasant conversation before bed were negatively associated with sleep duration whereas using alcohol to deliberately help full asleep was positively related to sleep duration. In contrast, disproportionately more behaviours were not significantly related to either sleep outcome, only some of which could be explained by individual differences, which suggests that more research is needed to determine the conditions under which these behaviours affect sleep, if at all.

Composite dietary antioxidant index and sleep health: a new insight from cross-sectional study

BACKGROUND

Low-quality sleep and obstructive sleep apnea (OSA) can result in series of chronic diseases. Healthy diet has been considered as an effective and simple strategy to optimize sleep quality. However, current evidence on the correlation of dietary composite antioxidant intake with sleep health remained obscure.

AIM OF THE STUDY

To determine the relationship of composite dietary antioxidant index (CDAI) and sleep health.

METHODS

Cross-sectional analyses were based on National Health and Nutrition Examination Survey (NHANES) 2005-2008. Dietary consumption was assessed by trained staff using 24-h diet recall method and CDAI was calculated based on previous validated approach that included six antioxidants. Sleep-related outcomes were self-reported by a set of questionnaires and classified into OSA, day sleepiness, and insufficient sleep. Weighted logistic regression was conducted to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic spline (RCS) regressions were also used to evaluate the dose-response of CDAI and three sleep-related outcomes.

RESULTS

A total of 7274 subjects included (mean age: 46.97 years) were enrolled in our study, including 3658 were females (52.54%) and 3616 were males (47.46%). Of them, 70.6%, 29.51%, and 35.57% of the subjects reported that they had OSA, day sleepiness and insufficient sleep, respectively. Logistic regression showed the highest quartile of CDAI was inversely associated with the risk of OSA (OR: 0.69, 95%CI: 0.49-0.97), day sleepiness (OR: 0.64, 95%CI: 0.44-0.94) and insufficient sleep (OR: 0.68, 95%CI: 0.50-0.92) compared with the lowest quartile. RCS showed linear relationship of CDAI and insufficient sleep but non-linear relationship of CDAI with OSA and day sleepiness.

CONCLUSIONS

Our results show that CDAI was non-linearly associated with lower risk of OSA and day sleepiness whereas a linear inverse association between CDAI and insufficient sleep was observed. These findings implicate that combined intake of antioxidants could be a promising and effective approach to optimize sleep quality for public.

Sex- and age-dependent associations of EPA and DHA with very short sleep duration in adults: a cross-sectional analysis

OBJECTIVES

This study aimed to compare the efficacy of dietary intake of eicosapentaenoic acid (EPA; 20:5 ω-3) and docosahexaenoic acid (DHA; 22:6 ω-3) on very short sleep duration (<5 h/night) in adults.

METHODS

The bootstrap method was used in the multinomial logistic regression to estimate the ORs and corresponding 95% confidence intervals (CIs) of very short sleep duration. We used rolling window method to analyze the effects of EPA and DHA dietary intakes on very short sleep durations in men and women over age. To illustrate the stability of the results for the selected window width, we built a shiny application.

RESULTS

Compared to the first quartile, the mean ORs of EPA intake on very short sleep duration and the corresponding 95% CIs for the second, third and fourth quartiles of EPA intake among men under 32 years old were 1.50 (0.56, 3.44) mg, 1.55 (0.59, 3.48) mg, and 3.99 (1.15, 10.01) mg, respectively. Among women over 44 years old, the ORs for DHA intake were 1.12 (0.81, 1.52) mg, 0.94 (0.68, 1.29) mg, and 0.62 (0.38, 0.98) mg for the second, third and fourth quartiles, respectively.

CONCLUSIONS

The associations of EPA and DHA with very short sleep duration are sex- and age-dependent. In males under the age of 32, a significant positive correlation exists between dietary EPA intake and very short sleep duration. For women above 44 years of age, an increase in DHA intake can notably ameliorate issues of very short sleep duration.

The impact of plant-rich diets on sleep: a mini-review

Plant-rich diets (PRDs), also referred to as plant based diets, have been shown to have beneficial effects on various chronic diseases and all-cause mortality. However, limited data are available on the effect of such diets on sleep and sleep disorders. In this review article, we explore existing evidence and potential mechanisms by which PRDs may impact sleep and sleepiness. High-fat diets are associated with drowsiness, while fiber-rich diets improve sleep quality. Anti-inflammatory diets may benefit patients with sleep disturbances, and diets rich in tryptophan and serotonin precursors may improve sleep quality. Isoflavones and polyphenols present in PRDs may also have a positive impact on sleep. Furthermore, diets rich in plants may reduce the risk of obstructive sleep apnea and associated daytime sleepiness. Overall, the current knowledge about PRDs in sleep and sleep disorders is limited, and further research is needed to explore the potential advantages of this dietary approach in sleep disorders.

Food Intake and Sleep Disorders in Children and Adolescents with Obesity

Over the last few decades, numerous scientific studies have investigated the possible association between sleep duration and adiposity during childhood, since it has been reported that sleep deprivation causes a related increase in caloric intake. Even though the underlying pathogenetic mechanisms are still under study and not completely known, the effect of dietetic habits and nutrient intake on sleep quality and patterns has been reported. The aim of this study is to explore the intricate interplay between food intake/diet patterns and pediatric sleep disturbances in children and adolescents with obesity, emphasizing the importance of not underestimating this aspect in the prevention and treatment of this complex disease. Recent evidence supports a high correlation between specific diet patterns and foods with sleep disturbances in children at all ages. Diets rich in fiber, fruit, vegetables, and anti-inflammatory nutrients and low in saturated fats seem to promote better sleep quality. Sleep disturbances are, in turn, risk factors for the development of obesity. Therefore, food strategies should be applied to counteract this harmful process. Unraveling the complex links between dietary habits, sleep patterns, and obesity is essential for developing effective strategies to combat this critical public health issue.

Higher intakes of nutrients and regular drinking are associated with habitual sleep duration in pre- and postmenopausal women with comorbidities

OBJECTIVES

We aimed to assess the association between nutrient intake, health-related behaviors, and habitual sleep duration in pre- and postmenopausal women.

DESIGN

A cross-sectional study.

PARTICIPANTS

2084 pre- and postmenopausal women aged 18-80 years old.

MEASUREMENTS

Nutrient intake and sleep duration were measured by a 24-hour recall approach and self-reports, respectively. We examined the association and interaction between comorbidities, nutrient intake, and sleep duration groups among 2084 women using data from KNHASES (2016-2018) and multinomial logistic regression.

RESULTS

In premenopausal women, we observed negative associations between very short (<5 hours)/short (5-6 hours)/long (≥9 hours) sleep duration and 12 nutrients (vitamin B1, B3, vitamin C, PUFA, n-6 fatty acid, iron, potassium, phosphorus, calcium, fiber, carbohydrate) and a positive association between retinol and short sleep duration (prevalence ratio (PR), 1.08; 95% CI, 1.01-1.15). In premenopausal women, interactions were found between comorbidities and PUFA (PR, 3.83; 95% CI, 1.56-9.41), n-3 fatty acid (PR, 2.43; 95% CI, 1.17-5.05), n-6 fatty acid (PR, 3.45; 95% CI, 1.46-8.13), fat (PR, 2.77; 95% CI, 1.15-6.64), and retinol (PR, 1.28; 95% CI, 1.06-1.53) for very short and short sleep duration, respectively. Interactions between comorbidities, vitamin C (PR, 0.41; 95% CI, 0.24-0.72), and carbohydrates (PR, 1.67; 95% CI, 1.05-2.70) for very short and short sleep duration in postmenopausal women, respectively. Regular drinking was positively associated with a risk of short sleep duration in postmenopausal women (PR, 2.74, 95% CI: 1.11-6.74).

CONCLUSIONS

Dietary intake and alcohol use were found to be involved in sleep duration, so healthcare staff should encourage women to maintain a healthy diet and reduce alcohol use to improve sleep duration.

The Role of Meeting Exercise and Nutrition Guidelines on Sleep during Pregnancy

Sleep disturbances are common during pregnancy. This study determined whether meeting physical activity or dietary guidelines during pregnancy was associated with improved sleep. Third trimester pregnant women (n = 49, 31.9 ± 4.1 years) completed physical activity and sleep questionnaires and then wore a wrist actigraph 24 h/day and completed three 24 h dietary recalls across two weeks. Participants who reported meeting physical activity guidelines (>150 min moderate-to-vigorous physical activity [MVPA]/week, n = 23) or dietary guidelines (≥1.1 g protein/kg body weight/day, n = 26 or ≥25 g fiber/day, n = 16) were compared to those who were physically inactive (<90 min/week) or did not meet dietary guidelines, respectively. Multivariate ANOVAs and Mann-Whitney U tests compared groups and correlations were conducted between physical activity, diet, and sleep variables. Physical activity groups did not differ in objective sleep measures (ps > 0.05); however, the active group reported better sleep quality (p = 0.049). Those who met protein guidelines exhibited longer sleep duration and less wake-after-sleep-onset (ps < 0.05). Across all participants, higher weekly MET mins/week of MVPA associated with better sleep quality (p = 0.02), and a diet higher in fat and lower in carbohydrates associated with longer sleep duration (ps < 0.05). Meeting physical activity and nutrition guidelines positively associates with improved sleep, with protein associated with objective measures and physical activity with subjective measures.

Association between patterns of nutrient intake and circulating vitamin D with sleep status among Iranian adults

Nutrient pattern analysis is an easy way to compare nutrient intakes across different nations due to the universality of nutrients nature. The purpose of this study was to examine the relationship between dietary nutrient patterns (NPs) and circulating 25(OH)D concentrations with sleep duration and sleep quality among Iranian adults. We used a multistage cluster random sampling method to enroll 535 adults in this cross-sectional investigation. A validated food frequency questionnaire was applied to evaluate typical dietary intakes. Fasting blood samples were obtained to determine levels of circulating 25(OH)D. Sleep characteristics were assessed using the Pittsburgh Sleep Quality Index (PSQI). Participants had a mean age of 42.57 years and 51.2% of them had insufficient or deficient levels of serum vitamin D. Three NPs were identified: "high animal protein", "high vegetable" and "high carbohydrate". After adjustments for potential confounders, no significant associations were observed between "high animal protein" pattern and short sleeping or sleep quality. Greater adherence to "high vegetable" NP was associated with lower odds of short sleeping (OR 0.24; 95% CI 0.10, 0.54) and poor sleep quality (OR 0.45; 95% CI 0.20, 1.05). Stratified analysis revealed that these associations were stronger in normal-weight participants. Greater adherence to "high carbohydrate" NP, on the other hand, was connected to higher odds of short sleeping (OR 2.83; 95% CI 1.20, 6.72). Low adherence to "high vegetable" pattern and vitamin D insufficiency/deficiency were jointly associated with increased odds of short sleeping (OR 3.42, 95% CI 1.42, 6.64). High adherence to pattern comprising mainly of vegetable nutrients was associated with a reduced likelihood of being short sleepers and having poor sleep quality in Iranian adults, especially among those with a normal weight. Lower adherence to vegetable NP and insufficient/deficient vitamin D levels were synergistically associated with greater likelihood of being short sleepers. Greater adherence to carbohydrate NP was associated with an increased likelihood of short sleeping.

The association between cholesterol/saturated fat index (CSI) and quality of sleep, and circadian rhythm among overweight and obese women: a cross-sectional study

BACKGROUND

The decline in sleep quality is one of the main public health problems affecting the global population. Some studies have shown that a high-fat diet may be linked to changes in circadian rhythm and sleep quality. The cholesterol/saturated fatty acid index (CSI) determines the amount of cholesterol and saturated fatty acid (SFA) in people's dietary patterns and can affect the quality of sleep and circadian rhythm. However, to date, no studies have investigated the effect of this index on these two variables. Therefore, our aim was to investigate the relationship between CSI on circadian rhythm and sleep quality in obese and overweight women.

METHOD

This cross-sectional study included 378 adult women who were obese or overweight. Using accepted techniques, anthropometric measurements, blood pressure readings, and biochemical variables were evaluated. A validated and trustworthy semi-quantitative food frequency questionnaire (FFQ 147 items) was used to gauge dietary intake. The CSI was measured to find out how much cholesterol and saturated fats were in the diet. Additionally, to assess circadian rhythm and sleep quality, respectively, the valid morning-evening questionnaire (MEQ) and Pittsburgh sleep quality index (PSQI) questionnaires were utilized.

RESULT

The results of the multinomial logistic regression model of our analysis showed that a significant association was observed between circadian rhythm status with CSI score, and participants with one higher unit of CSI had a 7.3% more chance of being in the eveningness group than being in morningness category in the crude model (OR: 1.07; 95% CI 1.00, 1.14; P = 0.026). This association remains marginally significant when adjusting for age, energy intake, BMI, job status, thyroid, and smoking status (OR = 1.08; 95% CI 1.00, 1.16; P = 0.051). The binary logistic regression model showed that after controlling for potentially confounding variables, there was no significant association between sleep quality with CSI score, however, those with one higher unit of CSI had 1.6% more chance of having sleep problems (OR: 1.01; 95% CI 0.96, 1.06; P = 0.503).

CONCLUSION

Our results indicated a direct marginally significant association between CSI with evening type in overweight and obese women. Future studies are needed to clarify the precise link between circadian rhythm and sleep behavior with fatty acid quality index.

The association of dietary approaches to stop hypertension (DASH) and Mediterranean diet with mental health, sleep quality and chronotype in women with overweight and obesity: a cross-sectional study

PURPOSE

Mental and sleep disorders are global public health problems, especially in Middle Eastern countries, and are significantly associated with circadian rhythm. This study sought to investigate the association between the dietary approaches to stop hypertension (DASH) and Mediterranean diet scores and mental health, sleep quality, and circadian rhythm.

METHODS

We enrolled 266 overweight and obese women, and depression, anxiety, and stress scale (DASS) score, Pittsburgh Sleep Quality Index (PSQI), and Morning-Evening Questionnaire (MEQ), were assessed. The Mediterranean and DASH diet score was measured using a validated semi-quantitative Food Frequency Questionnaire (FFQ). The physical activity was evaluated using the International Physical Activity Questionnaire (IPAQ). Analysis of variance and analysis of covariance, chi-square, and multinomial logistic regression tests were used as appropriate.

RESULTS

Our results showed that there was a significant inverse association between adherence to the Mediterranean diet and mild and moderate anxiety scores (p < 0.05). In addition, there was an inverse association between adherence to the DASH diet and the risk of severe depression and extremely severe stress scores (p < 0.05). Moreover, higher adherence to both dietary scores was associated with good sleep quality (p < 0.05). There was a significant relationship between circadian rhythm and the DASH diet (p < 0.05).

CONCLUSION

A significant association exists between a DASH and Mediterranean diet with sleep status, mental health, and chronotype in women of childbearing age with obesity and overweight.

LEVEL OF EVIDENCE

Level V, Cross-sectional observational study.

Diet quality, sleep and quality of life in Parkinson's disease: a cross-sectional study

BACKGROUND

Parkinson's disease (PD) is a neurodegenerative disorder characterised by motor and non-motor symptoms that impact quality of daily life, including diet and sleep. However, relatively little is known about dietary intake and quality in people with PD (PwP). Lifestyle factors, and how they relate to diet, are also insufficiently understood. The aims of this study were to investigate dietary intake and quality, sleep and quality of life in PwP, and to explore the relationships between these factors.

METHODS

Forty-five community-dwelling participants with PD (n = 45) were recruited to this cross-sectional study through the Cork Parkinson's Association, Ireland. Dietary intake was assessed using the EPIC food frequency questionnaire, and diet quality was assessed using the Healthy Diet Indicator. Dietary intakes were compared to Irish RDAs for adults > 65 years. Sleep duration and quality were subjectively measured using the PD Sleep Scale and Pittsburgh sleep quality index and objectively measured by actigraphy in a subset of participants (n = 27). QOL was measured using the validated PDQ-39 questionnaire.

RESULTS

Energy intake in PwP was significantly higher than that of the general population (2013 vs 1755 kcal/d, p = 0.01), despite their lower mean BMI (25.9 vs 27.7 kg/m2, p = 0.02). Intakes of carbohydrate, protein and fruits and vegetables were significantly higher in PwP compared to recommended and population intakes (all p < 0.01), but fibre intake was significantly lower than recommended (17.3 vs 25 g/d, p [Formula: see text] 0.05). Seventy-eight percent of participants had poor dietary quality, and poor sleep quality was associated with poor QOL.

CONCLUSIONS

Carbohydrates, protein, fruit and vegetable intakes were greater in PwP than population norms, but overall diet quality was low. Interventions to improve dietary and lifestyle factors may improve health and QOL in PwP.

Impact of Body Composition on Sleep and Its Relationship with Sleep Disorders: Current Insights

Sleep is involved in many physiological processes and is essential for both physical and mental health. Obesity and sleep deprivation due to sleep disorders are major public health issues. Their incidence is increasing, and they have a wide range of adverse health-related consequences, including life-threatening cardiovascular disease. The impact of sleep on obesity and body composition is well-known, and many studies have shown an association between insufficient or excessive sleep duration and obesity, body fat percentage, and weight gain. However, there is growing evidence of the effects of body composition on sleep and sleep disorders (particularly sleep disordered breathing) through anatomical and physiological mechanisms (nocturnal fluid shift, core body temperature, or diet). Although some research has been conducted on the bidirectional effects of sleep-disordered breathing and body composition, the specific effects of obesity and body composition on sleep and the underlying mechanisms that explain these effects remain unclear. Therefore, this review summarizes the findings on the effects of body composition on sleep and draws conclusions and proposals for future research in this field.

Vegetarians have an indirect positive effect on sleep quality through depression condition

This study aimed to assess the association between a vegetarian diet and sleep quality among Chinese healthy adults and explore potential contributing factors. A cross-sectional study was conducted with 280 vegetarians and 280 age- and sex-matched omnivores from Shanghai, China. The Pittsburgh Sleep Quality Index (PSQI) and the Central Depression Scale (CES-D) were used to assess sleep and depression condition, respectively. A validated semi-quantitative food frequency questionnaires (SQFFQ) was employed to assess dietary intakes, and body composition was measured with InBody720. Multi-linear regression and logistic regression analysis were performed for the data analysis. The sleep quality was significantly better in the vegetarians than in the omnivores (PSQI score: 2.80 ± 2.02 vs. 3.27 ± 1.90, p = 0.005). The proportion of vegetarians who reported self-satisfied sleep was also higher than that of the omnivores (84.6% vs. 76.1%, p = 0.011). However, after adjusted for the depression condition (CES-D scores), the difference in sleep quality between vegetarians and omnivores became insignificant (p = 0.053). Compared to omnivores, vegetarians had lower depression scores (CES-D: 9.37 ± 6.24 vs. 10.94 ± 7.00, p = 0.006). After controlling for confounding factors, there was positive association between depression condition and sleep quality (β = 0.106, 95%CI: 0.083 to 0.129, p < 0.001). Similarly, participants with better CES-D score had a lower risk of sleep disorders after controlling for the same confounding factors (OR = 1.109, 95%CI: 1.072 to 1.147, p < 0.001). Different contributing factors were reported in the vegetarian group and omnivore group. In conclusion, a vegetarian diet might improve sleep quality by moderating mental health, particularly depression condition.

Sleep physiology, pathophysiology, and sleep hygiene

Despite sleep's fundamental role in maintaining and improving physical and mental health, many people get less than the recommended amount of sleep or suffer from sleeping disorders. This review highlights sleep's instrumental biological functions, various sleep problems, and sleep hygiene and lifestyle interventions that can help improve sleep quality. Quality sleep allows for improved cardiovascular health, mental health, cognition, memory consolidation, immunity, reproductive health, and hormone regulation. Sleep disorders, such as insomnia, sleep apnea, and circadian-rhythm-disorders, or disrupted sleep from lifestyle choices, environmental conditions, or other medical issues can lead to significant morbidity and can contribute to or exacerbate medical and psychiatric conditions. The best treatment for long-term sleep improvement is proper sleep hygiene through behavior and sleep habit modification. Recommendations to improve sleep include achieving 7 to 9 h of sleep, maintaining a consistent sleep/wake schedule, a regular bedtime routine, engaging in regular exercise, and adopting a contemplative practice. In addition, avoiding many substances late in the day can help improve sleep. Caffeine, alcohol, heavy meals, and light exposure later in the day are associated with fragmented poor-quality sleep. These sleep hygiene practices can promote better quality and duration of sleep, with corresponding health benefits.

Time in Bed, Sleeping Difficulties, and Nutrition in Pregnant New Zealand Women

We consider the relationship between time in bed (TIB) and sleeping difficulties with demographic variables and nutrient intakes in the second (T2) and third (T3) trimester of pregnancy. Data were acquired from a volunteer sample of New Zealand pregnant women. In T2 and T3, questionnaires were administered, diets were obtained from one 24 h recall and three weighed food records, and physical activity was measured with the use of three 24 h diaries. In total, 370 women had complete information in T2 and 310 in T3. In both trimesters, TIB was associated with welfare or disability status, marital status and age. In T2, TIB was associated with work, childcare, education and pre-pregnancy alcohol consumption. There were fewer significant lifestyle covariates in T3. In both trimesters, TIB declined with increasing dietary intake, especially water, protein, biotin, potassium, magnesium, calcium, phosphorus and manganese. Adjusted for weight of dietary intake and welfare/disability, TIB declined with increasing nutrient density of B vitamins, saturated fats, potassium, fructose and lactose; and TIB increased with carbohydrate, sucrose and vitamin E. Subjective sleeping difficulties increased with the week of gestation, morning sickness severity, anxiety, dairy and saturated fat intake, and they decreased with fruit, vegetable and monounsaturated fat intake. The study highlights the changing influence of covariates throughout the pregnancy and corroborates several published findings on the relationship of diet and sleep.

Sleep Duration, Midday Napping, and Serum Homocysteine Levels: A Gene-Environment Interaction Study

The associations of sleep duration and midday napping with homocysteine (Hcy) levels, and whether these sleep behaviors modify the association between genetic predisposition and Hcy levels, has yet to be investigated. We included 19,426 participants without severe health conditions at baseline from the Dongfeng−Tongji cohort. In a subgroup of 15,126 participants with genetic data, a genetic risk score (GRS) based on 18 Hcy-related loci was constructed to test the gene−sleep interactions in Hcy. Hcy levels were higher in subjects with a long sleep duration (≥9 h) and midday napping (>90 min), as compared to those who reported a moderate sleep duration (7 to <8 h) and midday napping (1−30 min) (all p values < 0.05). A long sleep duration and midday napping showed a joint effect in increasing Hcy (p for trend < 0.001). Significant interactions regarding Hcy levels were observed for a long sleep duration with GRS and MTHFR rs1801133, and long midday napping with DPEP1 rs12921383 (all p values for interaction < 0.05). Overall findings indicated that a long sleep duration and midday napping were associated with elevated serum Hcy levels, independently and jointly, and amplified the genetic susceptibility to higher Hcy.

Interactions between heavy metals and sleep duration among pre-and postmenopausal women: A current approach to molecular mechanisms involved

The effects of heavy metals (cadmium, lead, and mercury) and their mixtures on sleep duration in pre-and postmenopausal women, particularly the molecular mechanisms, remain unknown. Here, we assessed the interaction between heavy metals and sleep duration among pre-and postmenopausal women (n = 1134). Furthermore, molecular mechanisms related to sleep disorders induced by studied heavy metals were further analyzed to support the previous findings. We found that serum lead levels were positively related to weekend and weekday sleep duration in premenopausal women. There were interactions between serum lead and mercury and menopausal status for sleep duration. Serum lead and mercury levels were shown to be inversely related to sleep duration in postmenopausal women. Despite the lack of statistically significant associations between mixed heavy metals and sleep duration, there were increasing trends in premenopausal women's sleeping patterns and decreasing trends in postmenopausal women's sleeping patterns. In silico analysis, IL1B, hsa-21-5p, hsa-887-3p, hsa-877-3p, and NR4A1 were identified as the most relevant genes, miRNAs, and transcription factors linked with sleep disorders induced by combined heavy metals (cadmium, lead, and mercury). Furthermore, "type 1 melanocortin receptor binding," "endocrine hormone secretion," "interleukin-1 receptor antagonist activity," "altered melanocortin system," and "sleep wake disorders" were identified as the predominant molecular mechanisms involved in the pathophysiology of sleep disorders induced by the studied heavy metals. Cut off point values and miRNA sponge templates for heavy metal exposure levels relevant to sleep disorders in pre- and postmenopausal women were reported. Future research is needed to verify our findings and provide insight into the molecular processes of long-term mixed heavy metal exposure in various populations, such as children and the elderly.

Association of Food Intake with Sleep Durations in Adolescents from a Capital City in Northeastern Brazil

(1) Background: During adolescence, there are significant changes in food consumption, such as reducing the consumption of in natura or minimally processed foods and increasing the consumption of ultra-processed foods. Thus, eating habits can influence sleep duration and, consequently, affect the quality of life of young people. This study thus aims to estimate the association of consumption of in natura or minimally processed, processed, and ultra-processed foods with sleep durations in adolescents. (2) Methods: This is a cross-sectional study including 964 adolescents (18 to 19 years old) from the 1997 to 1998 birth cohort in São Luís, Maranhão. Food consumption was assessed using the food frequency questionnaire (FFQ) and stratified based on the NOVA classification. Sleep duration was verified using accelerometry in hours. The analysis of the association between the consumption of in natura or minimally processed, processedand ultra-processed foods with sleep durations in adolescents used crude and adjusted linear regression (by gender, age, skin color, education, economic class, work, consumption of alcohol, smoking, screen time, physical activity, use of illicit drugs, anxiety, depressive symptoms, and lean and fat mass). A directed acyclic graph (DAG) was used to determine the minimum set of adjustment factors. (3) Results: Of the 964 individuals evaluated, 52.0% were female. The mean sleep duration was 6 h (± 0.95). In the crude and adjusted analyses, no association was observed between food consumption according to the degree of processing and adolescent sleep durations. (4) Conclusion: There was no association between the consumption of in natura or minimally processed, processed, and ultra-processed foods with sleep durations.

Do Sleep Disorders and Western Diet Influence Psoriasis? A Scoping Review

Western diet may trigger sleep disorders and vice versa, but their single and mutual effects on systemic inflammatory diseases (i.e., psoriasis) are far from being fully elucidated. At the same time, psoriatic patients display a great burden of sleep disorders and dysmetabolisms related to an unhealthy lifestyle (i.e., diet). These patients are also affected by a chronic disorder deeply modulated by environmental factors (i.e., sleep and diet) capable to influence drug-response and disease progression. Thus, we aimed to summarize the evidence in the literature that may highlight a potential link among psoriasis–diet–sleep in order to further promote a multidisciplinary approach to psoriatic patients in the scientific community.

Sleep Quality and Dietary Patterns in an Occupational Cohort of Police Officers

We examined the association between self-reported sleep quality, sleep duration, and dietary patterns among police officers in the Buffalo Cardio-Metabolic Occupational Stress (BCOPS) study.422 police officers aged 21-74 (2004-2009).We used a cross-sectional study design and obtained sleep quality and duration from responses to the 19-item Pittsburgh Sleep Quality Index. Using 46 energy-adjusted food groups derived from a 125-item food frequency questionnaire, we identified dietary patterns using exploratory factor analysis. Multiple linear regression analysis was used to examine the associations of sleep quality and duration with the derived dietary patterns.We identified major dietary patterns: fruits and vegetables (FV), dairy products, starches and fried foods, and meat and eggs. Individuals with poor sleep quality had a lower average FV score than those with optimal sleep (β [SE] = -0.32 [0.13]; p = .01). Significant interactions were observed between sex and the FV and dairy products dietary patterns, where women with poor sleep quality had a lower mean FV score compared to women with optimal sleep quality (β [SE] = -0.81 [0.29]; p = .01). Women with < 6 hours sleep duration had a lower mean dairy score compared to women with ≥ 7 hours sleep duration (β [SE] = -0.69 [0.29]; p = .02). We did not observe these associations among men.Among women, good sleep quality and long sleep duration were associated with a dietary pattern high in consumption of both fruits and vegetables and dairy products.Abbreviations: BCOPS: Buffalo Cardio-Metabolic Occupational Stress study; BMI: body mass index; FFQ: food frequency questionnaire; FV: fruits and vegetables; KMO: Kaiser-Meyer-Olkin test; MET: metabolic equivalent of task score; PSQI: Pittsburgh Sleep Quality Index questionnaire.

Sleep Quality: A Narrative Review on Nutrition, Stimulants, and Physical Activity as Important Factors

Sleep is a cyclically occurring, transient, and functional state that is controlled primarily by neurobiological processes. Sleep disorders and insomnia are increasingly being diagnosed at all ages. These are risk factors for depression, mental disorders, coronary heart disease, metabolic syndrome, and/or high blood pressure. A number of factors can negatively affect sleep quality, including the use of stimulants, stress, anxiety, and the use of electronic devices before sleep. A growing body of evidence suggests that nutrition, physical activity, and sleep hygiene can significantly affect the quality of sleep. The aim of this review was to discuss the factors that can affect sleep quality, such as nutrition, stimulants, and physical activity.

Anxiety-Induced Sleep Disturbance and Associated Lifestyle Behaviors According to Sex in Argentine Adolescents

Purpose

The aim of the current study was twofold: first, to determine the prevalence of anxiety-induced sleep disturbances among Argentine adolescents according to sex, and second, to identify the association between these sleep disturbances and lifestyle behaviors in this population.

Methods

This is a cross-sectional study with data from the Global School-based Student Health Survey (GSHS) in Argentina (2018). A total of 32,393 adolescents (aged 12–17 years; 53.4% girls) were included in the final analysis. Anxiety-induced sleep disturbances were assessed with the question “During the past 12 months, how often have you been so worried about something that you could not sleep at night?”

Results

The prevalence of anxiety-induced sleep disturbances was higher in girls (17.4%) than in boys (7.9%) (p < 0.001). In boys, results indicated that those who used marijuana (cannabis) (odds ratio [OR] = 1.46, 95% confidence interval [CI] 1.08–1.98), used amphetamine or methamphetamine (OR = 2.19, 95% CI 1.28–3.77), walked or biked to or from school (OR = 1.53, 95% CI 1.19–1.96), and spent 3 h or more in sedentary behaviors (OR = 1.35, 95% CI 1.05–1.74) were more likely to report anxiety-induced sleep disturbances. In girls, those who ate from a fast-food restaurant (OR = 1.24, 95% CI 1.05–1.47), consumed alcoholic beverages (OR = 1.45, 95% CI 1.19–1.75), smoked cigarettes (OR = 2.09, 95%CI 1.05–4.14), consumed any tobacco product (OR = 1.47, 95% CI 1.19–1.82), used amphetamine or methamphetamine (OR = 2.08, 95% CI 1.33–3.26), and those who spent 3 h or more in sedentary behaviors (OR = 1.32, 95% CI 1.11–1.57) were more likely to report frequent anxiety-induced sleep disturbances.

Conclusion

In conclusion, considerable sex differences were observed with respect to the prevalence of anxiety-related sleep disturbances and associated lifestyle aspects.

Sphinganine is associated with 24-h MAP in the non-sleepy with OSA

INTRODUCTION

Excessive daytime sleepiness is a debilitating symptom of obstructive sleep apnea (OSA) linked to cardiovascular disease, and metabolomic mechanisms underlying this relationship remain unknown. We examine whether metabolites from inflammatory and oxidative stress-related pathways that were identified in our prior work could be involved in connecting the two phenomena.

METHODS

This study included 57 sleepy (Epworth Sleepiness Scale (ESS) ≥ 10) and 37 non-sleepy (ESS < 10) participants newly diagnosed and untreated for OSA that completed an overnight in-lab or at home sleep study who were recruited from the Emory Mechanisms of Sleepiness Symptoms Study (EMOSS). Differences in fasting blood samples of metabolites were explored in participants with sleepiness versus those without and multiple linear regression models were utilized to examine the association between metabolites and mean arterial pressure (MAP).

RESULTS

The 24-h MAP was higher in sleepy 92.8 mmHg (8.4) as compared to non-sleepy 88.8 mmHg (8.1) individuals (P = 0.03). Although targeted metabolites were not significantly associated with MAP, when we stratified by sleepiness group, we found that sphinganine is significantly associated with MAP (Estimate = 8.7, SE = 3.7, P = 0.045) in non-sleepy patients when controlling for age, BMI, smoking status, and apnea-hypopnea index (AHI).

CONCLUSION

This is the first study to evaluate the relationship of inflammation and oxidative stress related metabolites in sleepy versus non-sleepy participants with newly diagnosed OSA and their association with 24-h MAP. Our study suggests that Sphinganine is associated with 24 hour MAP in the non-sleepy participants with OSA.

Higher HEI-2015 Scores Are Associated with Lower Risk of Sleep Disorder: Results from a Nationally Representative Survey of United States Adults

Whether there is an association between dietary quality and sleep disorder in American adults is unclear. We conducted this study to analyze whether dietary quality, using the Healthy Eating Index-2015 (HEI-2015) scores as the measure, was associated with self-reported sleep disorders. Data came from the National Health and Nutrition Examination Survey (2005–2014). Step-weighted logistic regression models were performed to explore the relationships between the HEI-2015 scores and sleep disorder. Weighted quantile sum regression model was used to identify the HEI-2015 components most strongly associated with sleep disorders. According to quartiles, HEI scores were categorized into inadequate (<25%), average (25–75%), and optimal (>75%). Compared to inadequate HEI status, average HEI status (OR: 0.961, 95%CI: 0.959–0.962) and optimal HEI status (OR: 0.913, 95% CI: 0.912–0.915) were associated with reduced risk of sleep disorder after multivariable adjustments. Greens and beans, added sugars, saturated fats, total vegetables and total protein foods were the top five important components for sleep disorders. Our results suggest that there is a statistically significant association between better dietary quality and reduced risk of sleep disorder among United States adults.

The independent association between vitamin B12 and insomnia in Chinese patients with type 2 diabetes mellitus: a cross-sectional study

Background/objectives

Insomnia is highly prevalent in patients with type 2 diabetes mellitus (T2DM). This study therefore evaluated the associations between various micronutrients and insomnia in patients with T2DM.

Subjects/methods

Between January 2018 and December 2020, a total of 418 T2DM patients with or without insomnia were recruited. Clinical and biochemical parameters, as well as micronutrient levels, were measured in each participant. Insomnia and sleep quality were assessed using the Athens Insomnia Scale and Pittsburgh Sleep Quality Index, respectively.

Results

Insomnia was found in 24.16% of patients with T2DM. Compared with T2DM patients without insomnia, patients with insomnia had significantly higher levels of vitamin B12 (VitB12). Increased VitB12 was an independent risk factor for insomnia (OR 1.61 [1.06–2.45], P = 0.03). A cut-off value of 517.50 pg/ml VitB12 (P = 0.01, AUC 0.61, standard error 0.04) predicted insomnia risk. Moreover, increased VitB12 levels in patients with insomnia were closely correlated with the use of mecobalamin.

Conclusions

This study suggests that elevated serum VitB12 level is independently associated with the incidence of insomnia and predicts increased insomnia risk in Chinese patients with T2DM.

Patterns of Eating Associated with Sleep Characteristics: A Pilot Study among Individuals of Mexican Descent at the US-Mexico Border

Introduction: Previous studies have linked sleep to risk of diabetes and obesity, at least partially via alterations in food intake. Diabetes and obesity are common among Hispanics/Latinos, and studies are needed to better clarify the role of sleep in health among this group. Utilizing the revised TFEQ-R-18, this study will examine whether eating behaviors such as cognitive restraint, emotional eating and uncontrolled eating are related to self-reported sleep experiences. Specifically, we hypothesized that poor eating habits would be associated with (1) more insomnia symptoms, (2) overall worse sleep quality, (3) increased daytime sleepiness, and (4) shorter sleep duration.Methods: Data were collected from N = 100 adults (age 18-60, 47% female) of Mexican descent in the city of Nogales, AZ (34% not born in the US). Surveys were presented in English or Spanish. Eating Patterns were assessed with the Three-Factor Eating Questionnaire (TFEQ), which resulted in a total score and subscales for "cognitive restraint," "uncontrolled eating," and "emotional eating." Insomnia was assessed with the use of the Insomnia Severity Index (ISI), Sleepiness with the use of the Epworth Sleepiness Scale (ESS), Sleep quality with the use of the Pittsburgh Sleep Quality Index (PSQI), and weekday and weekend sleep duration with the use of the Sleep Timing Questionnaire (STQ). Covariates included age, sex, Body Mass Index (BMI), education and immigrant status.Results: Overall TFEQ score (problematic eating) was positively associated with greater insomnia, poorer sleep quality, more sleepiness, and less weekend (but not weekday) sleep. Mean TFEQ score in the sample was 18.7 (range 0-51). In adjusted analyses, every point on the TFEQ was associated with 0.6 ISI points, 0.8 PSQI points, 0.5 ESS points, and 1.1 minutes of less weekend sleep duration. Regarding subscale scores, relationships were generally seenbetween sleep and emotional eating and unrestricted eating, and not cognitive restraint.Conclusions: Greater insomnia, poorer sleep quality, increased daytime sleepiness and decreased weekend sleep duration were associated with eating patterns at the US-Mexico border, particularly in the area of unrestricted eating and emotional eating. This suggests possible mechanisms linking sleep and obesity in Hispanic/Latinos.

PUFA ω-3 and ω-6 biomarkers and sleep: a pooled analysis of cohort studies on behalf of the Fatty Acids and Outcomes Research Consortium (FORCE)

BACKGROUND

n-3 and n-6 PUFAs have physiologic roles in sleep processes, but little is known regarding circulating n-3 and n-6 PUFA and sleep parameters.

OBJECTIVES

We sought to assess associations between biomarkers of n-3 and n-6 PUFA intake with self-reported sleep duration and difficulty falling sleeping in the Fatty Acids and Outcome Research Consortium.

METHODS

Harmonized, de novo, individual-level analyses were performed and pooled across 12 cohorts. Participants were 35-96 y old and from 5 nations. Circulating measures included α-linolenic acid (ALA), EPA, docosapentaenoic acid (DPA), DHA, EPA + DPA + DHA, linoleic acid, and arachidonic acid. Sleep duration (10 cohorts, n = 18,791) was categorized as short (≤6 h), 7-8 h (reference), or long (≥9 h). Difficulty falling asleep (8 cohorts, n = 12,500) was categorized as yes or no. Associations between PUFAs, sleep duration, and difficulty falling sleeping were assessed by cross-sectional multinomial logistic regression using standardized protocols and covariates. Cohort-specific multivariable-adjusted ORs per quintile of PUFAs were pooled with inverse-variance weighted meta-analysis.

RESULTS

In pooled analysis adjusted for sociodemographic characteristics and health status, participants with higher very long-chain n-3 PUFAs were less likely to have long sleep duration. In the top compared with the bottom quintiles, the multivariable-adjusted ORs (95% CIs) for long sleep were 0.78 (95% CI: 0.65, 0.95) for DHA and 0.76 (95% CI: 0.63, 0.93) for EPA + DPA + DHA. Significant associations for ALA and n-6 PUFA with short sleep duration or difficulty falling sleeping were not identified.

CONCLUSIONS

Participants with higher concentrations of very long-chain n-3 PUFAs were less likely to have long sleep duration. While objective biomarkers reduce recall bias and misclassification, the cross-sectional design limits assessment of the temporal nature of this relation. These novel findings across 12 cohorts highlight the need for experimental and biological assessments of very long-chain n-3 PUFAs and sleep duration.

Sleep duration as an independent factor associated with vitamin D levels in the EPISONO cohort

STUDY OBJECTIVES

Obstructive sleep apnea and short sleep duration have been separately associated with inadequate serum 25-hydroxyvitamin D [25(OH)D] levels. However, whether these 2 factors may concurrently influence 25(OH)D in the general population is unknown. We hypothesized that both obstructive sleep apnea and short sleep duration would be independently associated with lower concentrations of 25(OH)D in a sex-dependent manner.

METHODS

In this cross-sectional study, 712 individuals, part of the prospective EPISONO cohort (Brazil), underwent polysomnography, answered sleep questionnaires, and had their blood collected for serum 25(OH)D quantification.

RESULTS

Individuals with a sleep duration of < 6 hours had 2-fold increased odds of 25(OH)D < 20 ng/mL compared with those who reported 6 or more hours of sleep, even after adjusting for confounding factors. Subset sex analysis revealed that men with a sleep duration of < 6 hours had 4-fold increased odds of 25(OH)D < 20 ng/mL. In women, short sleep duration was not associated with lower 25(OH)D levels. The presence of obstructive sleep apnea (as classified according to the individual's apnea-hypopnea index) was not independently related to 25(OH)D concentrations in men or women. Sleep parameters, including sleep latency and sleep efficiency, had no association with 25(OH)D < 20 ng/mL.

CONCLUSIONS

Short sleep, but not apnea-hypopnea index, was an independent factor associated with low 25(OH)D serum levels in men, but not in women. Apnea-hypopnea index scores were not associated with 25(OH)D levels in either sex. These results raise the possibility of investigating sex-specific characteristics, such as gonadal hormone regulation, and re-evaluating obstructive events by classifying them in mild, moderate, and severe obstructive sleep apnea.

CITATION

de Oliveira DL, Dokkedal-Silva V, Fernandes GL, Kim LJ, Tufik S, Andersen ML. Sleep duration as an independent factor associated with vitamin D levels in the EPISONO cohort. J Clin Sleep Med. 2021;17(12):2439-2449.

Sleep duration and quality are associated with nutrient intake in elite female athletes

OBJECTIVES

Sleep is important for athlete health and performance; however, the relationship between diet and sleep in elite female athletes is not well understood. This study examined associations between energy, macronutrient and micronutrient intakes, and sleep in elite female Australian footballers.

DESIGN

Prospective cohort study.

METHODS

Thirty-two players had their diet and sleep monitored for 10 consecutive days during pre-season. Sleep was monitored using activity monitors and sleep diaries. Sleep outcomes included sleep duration, sleep onset latency (SOL), wake time after sleep onset (WASO), and sleep efficiency (SE). Dietary intake was monitored using the smartphone applications Easy Diet Diary and FoodWorks. Relationships between nutrient intake and sleep were assessed using Generalised Estimating Equations.

RESULTS

For each 1-g·kg^-1 increase in carbohydrate intake, WASO increased by 3.6 min (p = 0.007) and SE decreased by 0.6% (p = 0.007). For each 1-g increase in daily saturated fat intake, SOL decreased by 0.27 min (p = 0.030). For each 1-mg increase in iron intake, sleep duration increased by 0.55 min (p < 0.001). For each 1-mg increase in zinc intake, SE increased by 0.23% (p = 0.006). For each 1-μg increase in vitamin B12 intake, WASO decreased by 1.72 min (p < 0.02) and SE increased by 0.40% (p = 0.033).

CONCLUSIONS

Nutrient intake in elite female athletes is associated with sleep and may contribute to sleep problems. Research should explore causal relationships between nutrient intake and sleep, and the efficacy of dietary interventions for improving sleep in female athletes with nutrient deficiencies.

Association between low carbohydrate diet (LCD) and sleep quality by mediating role of inflammatory factors in women with overweight and obesity: A cross-sectional study

Poor sleep quality can lead to increased obesity. Low carbohydrate diet (LCD) is considered as an approach for sleep quality and obesity improvement. The aim of this investigation is to evaluate the relationship between LCD and sleep quality with the mediatory effect of inflammatory markers including transforming growth factor-β (TGF-β), high-sensitivity C-reactive protein (hs-CRP), total antioxidant capacity: In our cross-sectional study, 304 obese women aged from 19 to 50 years were enrolled. Body mass index (BMI) in these women ranged from 25.2 to 48.3 kg/m2. LCD score was assessed by a 147- item semi-quantitative food frequency questionnaire (FFQ). The Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep quality. FFQ and PSQI questionnaires are completed simultaneously by the participants. Biochemical indicators (inflammatory markers) were measured and anthropometric components were evaluated. The relationship between sleep quality and LCD with quantitative variables was assessed by independent sample t-test and with qualitative variables by chi-square test. Binary logistic regression was used to estimate confounding variables including age, job, stress, weight to investigate the relationship between LCD and sleep. Following of LCD had a significant negative relationship with PSQI score. It can be said that with increasing LCD adherence, the possibility of poor sleep quality decrease (OR = 0.43, 95% CI = 0.19-0.94,p = .03). It was also showed, hs-CRP (OR = 0.61, 95% CI = 0.3-1.21, p = .16) and TAC (OR = 0.6, 95% CI = 0.25-1.4, p = 0.24), eliminated the significance of the association and it is possible that they play a mediating role in this relationship Following the LCD can have a positive effect on improving PSQI scores by reduction in inflammatory markers levels.

Eucaloric Balanced Diet Improved Objective Sleep in Adolescents with Obesity

Background: A better understanding of the influence of energy balance on sleep in adolescents, particularly those with obesity, could help develop strategies to optimize sleep in these populations. The purpose of this study was to investigate sleep under ad libitum-vs-controlled diets adjusted to energy requirement (eucaloric) among adolescents with obesity and their normal weight controls. Methods: Twenty-eight male adolescents aged between 12 and 15 years, n = 14 adolescents with obesity (OB: BMI ≥ 90th centile) and n = 14 normal weight age matched controls (NW), completed an experimental protocol comprising ad libitum or eucaloric meals for three days, in random order. During the third night of each condition, they underwent in home polysomnography (PSG). Results: An interaction effect of energy intake (EI) was detected (p < 0.001). EI was higher during ad libitum compared to the eucaloric condition (p < 0.001) and in OB compared to NW (p < 0.001) in the absence of any substantial modification to macronutrient proportions. Analyses of energy intake distribution throughout the day showed a significant interaction with both a condition and group effect during lunch and dinner. Sleep improvements were noted in OB group during the eucaloric condition compared to ad libitum with reduced sleep onset latency and N1 stage. Sleep improvements were correlated to reduced EI, especially during the evening meal. Conclusion: Simply adjusting dietary intake to energy requirement and reducing the energy proportion of the evening meal could have therapeutic effects on sleep in adolescents with obesity. However, positive energy balance alone cannot justify worsened sleep among adolescents with obesity compared to normal weight counterparts.

Association of Daytime Napping with chronic diseases among Tibetan people in China: a cross-sectional study

BACKGROUND

Obesity, diabetes, and hypertension, as three of the most prevalent chronic diseases, remain a daunting health challenge. However, to our knowledge, no study has made a thorough examination of the association between the three chronic diseases and daytime napping, a widely accepted behavior in many countries. This is especially necessary among Tibetan populations, whose lifestyles and health outcomes may be unique, yet patterns of chronic diseases and napping are under-examined. Thus, we sought to explore the aforementioned association in the Tibetan population of China.

METHODS

A total of 2902 participants aged 45-79 in 2019 were included. Multivariate logistic regressions were conducted in 2020. The sex disparity was examined through interaction and stratified analyses.

RESULTS

Hypertension (40.7%) was more prevalent than obesity (20.2%) and diabetes (21.6%). Comparing to non-nappers, those who napped were more likely to have any conditions (OR = 1.30, 95% CI = 1.04-1.62 for 1-59 min/day group and OR = 1.40, 95% CI = 1.10-1.80 for ≥60 min/day group). Participants who had 1-59 min/day of napping were more likely to develop obesity (OR = 1.37, 95% CI = 1.07-1.75), and ≥ 60 min/day of napping was associated with diabetes (OR = 1.33, 95% CI = 1.01-1.74). The interactions between napping and sex were not statistically significant in the models.

CONCLUSIONS

The study revealed napping was unfavorably associated with obesity, diabetes, and any conditions in Tibetan people living on the Tibetan Plateau. Future interventions regarding the three chronic diseases may pay more attention to napping.

TRIAL REGISTRATION

Not applicable.

Eating habits are associated with subjective sleep quality outcomes among university students: findings of a cross-sectional study

PURPOSE

This study investigated the relationships between eating habits and sleep quality among university students.

METHODS

In a cross-sectional study, university students completed a self-report questionnaire to assess eating habits and meal timing. We assessed subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire and examined the associations between eating habits and overall sleep quality and its components.

RESULTS

Four hundred ninety-eight students participated in the study. Students who used to skip breakfast, ate late-night snacks, and replaced meals with snacks were at 1.20 times, 1.24 times, and 1.25 times higher likelihood of having poor overall sleep quality, respectively. Multiple logistic regression analysis showed that skipping breakfast (r =  - 0.111, P = 0.007), late-night snacks (r =  - 0.109, P = 0.007), replacing meals with snacks (r =  - 0.126, P = 0.002), and irregular mealtimes (r =  - 0.094, P = 0.018) were the best correlates with poor sleep quality. After adjustment to demographic variables, replacing meals with snacks followed by skipping breakfast were the best independent associations with poor sleep quality by the PSQI.

CONCLUSIONS

Eating habits and meal timing were significantly associated with sleep quality. We speculate that healthy eating habits may lead to improved sleep quality and sleep components among university students.

Effectiveness of a customised mobile phone text messaging intervention supported by data from activity monitors for improving lifestyle factors related to the risk of type 2 diabetes among women after gestational diabetes: protocol for a multicentre randomised controlled trial (SMART MUMS with smart phones 2)

INTRODUCTION

Gestational diabetes (GDM) contributes substantially to the population burden of type 2 diabetes (T2DM), with a high long-term risk of developing T2DM. This study will assess whether a structured lifestyle modification programme for women immediately after a GDM pregnancy, delivered via customised text messages and further individualised using data from activity monitors, improves T2DM risk factors, namely weight, physical activity (PA) and diet.

METHODS AND ANALYSIS

This multicentre randomised controlled trial will recruit 180 women with GDM attending Westmead, Campbelltown or Blacktown hospital services in Western Sydney. They will be randomised (1:1) on delivery to usual care with activity monitor (active control) or usual care plus activity monitor and customised education, motivation and support delivered via text messaging (intervention). The intervention will be customised based on breastfeeding status, and messages including their step count achievements to encourage PA. Messages on PA and healthy eating will encourage good lifestyle habits. The primary outcome of the study is healthy lifestyle composed of weight, dietary and PA outcomes, to be evaluated at 6 months. The secondary objectives include the primary objective components, body mass index, breastfeeding duration and frequency, postnatal depression, utilisation of the activity monitor, adherence to obtaining an oral glucose tolerance test post partum and the incidence of dysglycaemia at 12 months. Relative risks and their 95% CIs will be presented for the primary objective and the appropriate regression analysis, adjusting for the baseline outcome results, will be done for each outcome.

ETHICS AND DISSEMINATION

Ethics approval has been received from the Western Sydney Local Health District Human Research Ethics Committee (2019/ETH13240). All patients will provide written informed consent. Study results will be disseminated via the usual channels including peer-reviewed publications and presentations at national and international conferences.

TRIAL REGISTRATION NUMBER

ACTRN12620000615987; Pre-results.

Association of plant-based diet index with inflammatory markers and sleep quality in overweight and obese female adults: A cross-sectional study

BACKGROUND

Inflammation and sleep disturbances increase the risk of multiple diseases, including cardiovascular disease, type 2 diabetes and dementia. Since diet plays a significant role in inflammatory responses and sleep quality, this study aimed to investigate the association of a plant-based diet index (PDI) with sleep quality and inflammatory markers in overweight and obese women.

METHODS

390 overweight and obese women aged 18-48 years participated in this cross-sectional study. A validated food frequency questionnaire (FFQ) was used to create an overall PDI, healthful plant-based diet index (hPDI) and unhealthful plant-based diet index (uPDI). Sleep quality was assessed by Pittsburgh Sleep Quality Index (PSQI). Higher scores on the PSQI were indicative of poor sleep. Anthropometric measurements and serum concentrations of high-sensitivity C-reactive protein (hs-CRP), interleukin 1 beta (IL-1β) and transforming growth factor-beta (TGF-β) were evaluated. Linear regression models were used to determine the association between exposure and outcomes.

RESULTS

After taking potential confounders into account, we found a significant inverse association between adherence to hPDI and hs-CRP (β = -0.14, 95% confidence interval [CI]: -0.22,0.06, P = .001) and a significant positive association between uPDI and hs-CRP (β = 0.13, 95% CI: 0.05,0.21, P = .001). Overall, PDI was significantly associated with TGF-β (β = 2.04, 95% CI: 0.54,3.55, P = .008). No association was detected between PDI indices and IL-1β. Higher adherence to uPDI was significantly associated with higher PSQI score (lower sleep quality) (β= 0.20, 95% CI:0.007,0.40, P = .04). A significant positive association was found between TGF-β (β = 0.05, 95% CI:0.005,0.10, P = .03) and hs-CRP (β = 0.32, 95% CI:0.02,0.62, P = .03) with PSQI.

CONCLUSION

Our findings indicated a significant association between adherence to a plant-based diet with inflammation and sleep quality in obese and overweight females. WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Sleep is an essential part of life, and sleep quality has a significant impact on individual well-being and performance. There is a bidirectional relationship between disturbed sleep and elevated levels of inflammatory markers. Diet plays a major part in sleep quality and its related health consequences. Plant-based diets are associated with lower risk of chronic diseases such as coronary artery disease (CAD), type 2 diabetes, obesity and reduced level of inflammation. WHAT DOES THIS ARTICLE ADD?: Adherence to a healthful plant-based diet is associated with lower level of hs-CRP, while adherence to an unhealthful plant-based diet is associated with higher concentrations of hs-CRP. Adherence to an unhealthful plant-based diet is associated with lower sleep quality.

Laurent CW, Spencer RMC. Unhealthy Diet Is Associated With Poor Sleep in Preschool-Aged Children

Unhealthy dietary choices are associated with poor sleep in children through adults. Yet, how diet and sleep are related in early childhood, when diet is reliant on parent choices around food availability, is unknown. The authors aimed to explore how frequency of fruit, vegetable, fast food, and soda consumption are associated with preschool children's sleep quality. They also considered how parenting factors may impact the relationship between children's sleep and diet. Actigraphy data were collected from 383 children 33-70 months old. Caregivers reported on child food and beverage frequency, demographics, and health items. Parenting strategies were assessed using the Parenting Scale. Multiple linear regression was used to examine associations between sleep and dietary measures with socioeconomic status, race-ethnicity, physical activity, and body mass index as covariates. Shorter nap duration was associated with more frequent consumption of fruits and vegetables (B = -3.6, p = .03). Shorter nighttime and 24-hr sleep durations were associated with more frequent consumption of fast food (B = -6.5, p = .01; B = -5.8, p = .01). Shorter nighttime sleep and later sleep onset were associated with more frequent soda consumption (B = -9.2, p = .01; B = 0.23, p = .001). Use of ineffective parenting strategies was negatively associated with fruit and vegetable consumption (r = -.29, p = .01) and positively associated with soda consumption (r = .25, p = .02) but was unrelated to sleep measures. Thus, ineffective parenting strategies may underlie child access to unhealthy foods, which, in turn, contributes to poor sleep. Encouraging healthier dietary habits and educating caregivers on how to reinforce such practices may lead to better sleep outcomes in early childhood.

Culturally-consistent diet among individuals of Mexican descent at the US-Mexico border is associated with sleep duration and snoring

BACKGROUND

Existing studies show that consuming food consistent with one's culture reduces cardiometabolic risk. However, few studies have assessed whether these dietary choices influence sleep health. Accordingly, this study assessed how Mexican food consumption by individuals of Mexican descent residing at the US-Mexico border, was associated with various measures of sleep, after accounting for acculturation.

METHODS

Data were provided by 100 adults between the ages of 18-60, in the city of Nogales, AZ. Questionnaires were provided in either Spanish or English. Acculturation was assessed with the Acculturation Scale for Mexican-Americans (ARSMA-II), with an additional question, asking how often "my family cooks Mexican foods." Frequency of cooking Mexican food was coded as either "yes" or "no." Sleep was assessed, using validated measures that include the Insomnia Severity Index (ISI), the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index (PSQI), and sleep duration with the item "how many hours of actual sleep did you get at night?" Regression models estimated the associations between sleep health variables as outcomes and consumption of Mexican food as the independent variable. Covariates included age, sex, and acculturation scores. Parental education level was also included, as an indicator of childhood socioeconomic status and since food culture likely involves parents.

RESULT

We found that among individuals who identified as Mexican-Americans who consumed culturally-consistent foods, was associated with, on average, 1.41 more hours of sleep (95% CI 0.19, 2.62; p = 0.024) and were less likely to report snoring (OR: 0.25; 95% CI 0.07, 0.93; p = 0.039). Consuming Mexican food was not associated with sleep quality, insomnia severity or sleepiness.

CONCLUSION

Individuals of Mexican descent residing at the US-Mexico border who regularly consumed Mexican food, reported more sleep and less snoring. Mexican acculturation has been shown previously to improve sleep health. This is likely due to consumption of a culturally- consistent diet. Future studies should examine the role of acculturation in sleep health, dietary choices, and subsequent cardiometabolic risk.

A screen for sleep and starvation resistance identifies a wake-promoting role for the auxiliary channel unc79

The regulation of sleep and metabolism are highly interconnected, and dysregulation of sleep is linked to metabolic diseases that include obesity, diabetes, and heart disease. Furthermore, both acute and long-term changes in diet potently impact sleep duration and quality. To identify novel factors that modulate interactions between sleep and metabolic state, we performed a genetic screen for their roles in regulating sleep duration, starvation resistance, and starvation-dependent modulation of sleep. This screen identified a number of genes with potential roles in regulating sleep, metabolism, or both processes. One such gene encodes the auxiliary ion channel UNC79, which was implicated in both the regulation of sleep and starvation resistance. Genetic knockdown or mutation of unc79 results in flies with increased sleep duration, as well as increased starvation resistance. Previous findings have shown that unc79 is required in pacemaker for 24-hours circadian rhythms. Here, we find that unc79 functions in the mushroom body, but not pacemaker neurons, to regulate sleep duration and starvation resistance. Together, these findings reveal spatially localized separable functions of unc79 in the regulation of circadian behavior, sleep, and metabolic function.

Practice nurse-supported weight self-management delivered within the national child immunisation programme for postnatal women: a feasibility cluster RCT

BACKGROUND

Pregnancy is a high-risk time for excessive weight gain. The rising prevalence of obesity in women, combined with excess weight gain during pregnancy, means that there are more women with obesity in the postnatal period. This can have adverse health consequences for women in later life and increases the health risks during subsequent pregnancies.

OBJECTIVE

The primary aim was to produce evidence of whether or not a Phase III trial of a brief weight management intervention, in which postnatal women are encouraged by practice nurses as part of the national child immunisation programme to self-monitor their weight and use an online weight management programme, is feasible and acceptable.

DESIGN

The research involved a cluster randomised controlled feasibility trial and two semistructured interview studies with intervention participants and practice nurses who delivered the intervention. Trial data were collected at baseline and 3 months later. The interview studies took place after trial follow-up.

SETTING

The trial took place in Birmingham, UK.

PARTICIPANTS

Twenty-eight postnatal women who were overweight/obese were recruited via Birmingham Women's Hospital or general practices. Nine intervention participants and seven nurses were interviewed.

INTERVENTIONS

The intervention was delivered in the context of the national child immunisation programme. The intervention group were offered brief support that encouraged self-management of weight when they attended their practice to have their child immunised at 2, 3 and 4 months of age. The intervention involved the provision of motivation and support by nurses to encourage participants to make healthier lifestyle choices through self-monitoring of weight and signposting to an online weight management programme. The role of the nurse was to provide regular external accountability for weight loss. Women were asked to weigh themselves weekly and record this on a record card in their child's health record ('red book') or using the online programme. The behavioural goal was for women to lose 0.5-1 kg per week. The usual-care group received a healthy lifestyle leaflet.

MAIN OUTCOME MEASURES

The primary outcome was the feasibility of a Phase III trial to test the effectiveness of the intervention, as assessed against three traffic-light stop-go criteria (recruitment, adherence to regular self-weighing and registration with an online weight management programme).

RESULTS

The traffic-light criteria results were red for recruitment (28/80, 35% of target), amber for registration with the online weight loss programme (9/16, 56%) and green for adherence to weekly self-weighing (10/16, 63%). Nurses delivered the intervention with high fidelity. In the qualitative studies, participants indicated that the intervention was acceptable to them and they welcomed receiving support to lose weight at their child immunisation appointments. Although nurses raised some caveats to implementation, they felt that the intervention was easy to deliver and that it would motivate postnatal women to lose weight.

LIMITATIONS

Fewer participants were recruited than planned.

CONCLUSIONS

Although women and practice nurses responded well to the intervention and adherence to self-weighing was high, recruitment was challenging and there is scope to improve engagement with the intervention.

FUTURE WORK

Future research should focus on investigating other methods of recruitment and, thereafter, testing the effectiveness of the intervention.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN12209332.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 49. See the NIHR Journals Library website for further project information.

The Relationship Between Diet and Sleep in Older Adults: a Narrative Review

PURPOSE OF REVIEW

Older adults more frequently experience reduced sleep quality and quantity compared to younger adults. Diet is one modifiable lifestyle factor that may influence sleep outcomes in older adults. The purpose of this review is to synthesise the current literature investigating the impact of diet, including foods and nutrients, on the sleep quality and quantity of older adults.

RECENT FINDINGS

Overall, the observational and intervention studies suggest that following a Mediterranean diet, and the consumption of certain food items (e.g. milk), and nutrients (e.g. vitamin D and vitamin E) may influence (improve or reduce) sleep quality and quantity. This review describes the potential efficacy for dietary factors to improve sleep outcomes in older adults. However, given the heterogeneity of included studies in this review (i.e. aims, methodologies, and outcomes assessed), it is difficult to consolidate the available evidence to make specific recommendations. More targeted research exploring the relationship between diet and sleep in older adults is needed to strengthen the current evidence base.

Dietary patterns and sleep disorders in Mexican adults from a National Health and Nutrition Survey

Given the high prevalence of multiple non-communicable chronic diseases in Mexico, the aim of the present study was to assess the association between dietary patterns and sleep disorders in a national representative sample of 5076 Mexican adults (20–59 years) from the 2016 National Health and Nutrition Survey. Through a cross-sectional study, we used the Berlin sleep symptoms questionnaire to estimate the proportion of adults with insomnia, obstructive sleep apnoea (OSA) and other related problems such as daytime symptoms and inadequate sleep duration. Dietary data were collected through a seven-day semi-quantitative food frequency questionnaire, and dietary patterns were determined through cluster analysis. Associations between dietary patterns and sleep disorders were assessed by multivariate logistic regression models adjusted for age, sex, well-being, rural/urban area type, geographical region, tobacco use, physical activity level and energy intake. Three dietary patterns were identified: traditional (high in legumes and tortilla), industrialised (high in sugar-sweetened beverages, fast foods, and alcohol, coffee or tea) and mixed (high in meat, poultry, fruits and vegetables). Multivariate logistic regression showed that the industrialised pattern yielded higher odds for daytime symptoms (OR 1⋅49; 95 % CI 1⋅12, 1⋅99) and OSA (OR 1⋅63; 95 % CI 1⋅21, 2⋅19) compared with the traditional pattern. In conclusion, dietary patterns are associated with sleep disorders in Mexican adults. Further research is required to break the vicious cycle of poor-quality diet, sleep symptoms and health.

A Systematic Review, Meta-Analysis and Meta-Regression on the Effects of Carbohydrates on Sleep

This study aimed to assess the effects of quantity, quality and periodization of carbohydrates consumption on sleep. PubMed, SCOPUS and Cochrane Library were searched through October 2020. Data were pooled using random-effects meta-analysis. Eleven articles were included in the meta-analysis which consisted of 27 separate nutrition trials, resulting in 16 comparison data sets (sleep quantity n = 11; sleep quality n = 5). Compared to high carbohydrate (HCI), low carbohydrate intake (LCI) moderately increased duration and proportion of N3 sleep stage (ES = 0.37; 95% CI = 0.18, 0.56; p < 0.001 and ES = 0.51; 95% CI = 0.33, 0.69; p < 0.001, respectively). HCI prolonged rapid eye movement (REM) stage duration (ES = −0.38; 95% CI = 0.05, −8.05; p < 0.001) and proportion (ES = −0.46; 95% CI = −0.83, −0.01; p < 0.001), compared to LCI. The quality of carbohydrate intake did not affect sleep stages. Meta-regression showed that the effectiveness of carbohydrate quantity and quality in sleep onset latency was significantly explained by alterations of carbohydrate intake as a percentage of daily energy intake (R² = 25.87, p = 0.018) and alterations in the glycemic load (R² = 50.8, p = 0.048), respectively. Alterations in glycemic load partially explained the variance of the effectiveness of carbohydrate quality in sleep efficiency (R² = 89.2, p < 0.001) and wake after sleep onset (R² = 64.9, p = 0.018). Carbohydrate quantity was shown to affect sleep architecture, and especially N3 and REM sleep stages. Alterations in both quantity and quality of carbohydrate intake showed a significant effect on sleep initiation. Variations in carbohydrate quality significantly affected measures of sleep continuation. Further studies are needed to assess the effect of long-term carbohydrate interventions on sleep.

Dietary Factors and Sleep Quality Among Hemodialysis Patients in Malaysia

OBJECTIVES

Poor sleep quality is a commonly seen problem in hemodialysis patients. This study investigated the associations between dietary factors and sleep quality among hemodialysis patients.

DESIGN AND METHODS

This is a cross-sectional study conducted among 184 eligible hemodialysis patients at four dialysis units in Malaysia. Three days dietary recall were used in the analysis of dietary intake and behavior. Sleep quality was assessed through Pittsburgh Sleep Quality Index.

RESULTS

More than half of the patients were poor sleepers. Among the sleep components, sleep latency affected patients the most, with the use of sleep medications was relatively low. A majority of the patients had inadequate dietary intake of energy (88%) and protein (75%). Dietary protein, potassium adjusted for body weight, and sodium intake were significantly increased in poor sleepers. Lower percentage of energy from carbohydrates; higher percentage of energy from fats; higher intakes of dietary protein, fat, phosphorus, and sodium were correlated with poorer sleep quality and its components. Skipping dinner on non-dialysis days and having supper on dialysis days were associated with poor sleep quality.

CONCLUSION

Poor sleep is prevalent among hemodialysis patients. Sleep quality of hemodialysis patients was highly associated with certain dietary factors. Periodical assessment of sleep quality and dietary intake is necessary to identify poor sleepers with inappropriate dietary intake to allow effective clinical and nutritional interventions to improve the sleep quality and nutritional status of these patients.

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.

[Sleep-related problems and associated factors among the Brazilian population: National Health Survey, 2013]

The scope of this study was to estimate the frequency of sleep-related problems and associated factors. It was a study based on data from the National Health Survey conducted in Brazil in 2013. Sleep-related problems were assessed with the question "How often have you had sleep problems in the last two weeks, such as difficulty falling asleep, waking up frequently during the night or sleeping more than usual?" The answers were grouped into: none of the days, less than half of the days and more than half of the days. Of the individuals evaluated, 71.1% reported having no problems with sleep on any day, 14.0% on at least half of the days and 14.9% on more than half of the days. The highest frequencies of sleep-related problems were reported by women and more advanced age. For men and women, smoking, alcohol abuse, physical inactivity, sedentary behavior, and high blood pressure were significantly associated with the frequency of sleep problems on more than half of the days, and also excess weight for women. Thus, the frequency of sleep-related problems in the Brazilian population was high. Women, older individuals with lifestyle-related risk behaviors, high blood pressure, and overweight were the highest risk subgroups.