Background/Objectives: Sleep is essential for athletes. However, the impact of dietary habits on sleep quality in female endurance athletes at risk for low energy availability (LEA) is underexplored. This was a pilot study to examine the correlation between dietary patterns and sleep quality in healthy female endurance athletes. Methods: Twenty-four female endurance athletes recorded their dietary intake and sleeping habits for 6 days. Dietary intake data were collected via meal logs and photos. Sleep parameters were tracked using the Fitbit Charge 3 device. Correlation analyses were performed to explore the associations between macronutrient intake and sleep. Results: The athletes' mean consumption was 2049.3 ± 396.9 kcal/day (52.9% carbohydrates, 28.2% fat, and 17.2% protein). One-third of the athletes had poor sleep quality, and thirty-eight percent experienced high daytime sleepiness. A higher protein intake was correlated with a lower awake time (R = -0.491; p = 0.015), and fat intake was related to a lower duration of deep sleep (R = -0.477; p = 0.019). Deep sleep was negatively correlated with fat intake during dinner (R = -0.417; p = 0.042) and was positively correlated with carbohydrate intake (R = 0.417; p = 0.042). Conclusions: In healthy female endurance athletes without LEA, dietary fat intake, especially at dinner, negatively affects deep sleep. Meanwhile, carbohydrates promote deep sleep. Therefore, optimizing macronutrient balance during evening meals may enhance sleep quality and, consequently, athletic performance.

Few studies have explored the relationship between macronutrient intake and sleep outcomes using daily data from mobile apps.

This cross-sectional study aimed to examine the associations between macronutrients, dietary components, and sleep parameters, considering their interdependencies.

We analyzed data from 4825 users of the Pokémon Sleep and Asken smartphone apps, each used for at least 7 days to record objective sleep parameters and dietary components, respectively. Multivariable regression explored the associations between quartiles of macronutrients (protein; carbohydrate; and total fat, including saturated, monounsaturated, and polyunsaturated fats), dietary components (sodium, potassium, dietary fiber, and sodium-to-potassium ratio), and sleep variables (total sleep time [TST], sleep latency [SL], and percentage of wakefulness after sleep onset [%WASO]). The lowest intake group was the reference. Compositional data analysis accounted for macronutrient interdependencies. Models were adjusted for age, sex, and BMI.

Greater protein intake was associated with longer TST in the third (+0.17, 95% CI 0.09-0.26 h) and fourth (+0.18, 95% CI 0.09-0.27 h) quartiles. In contrast, greater fat intake was linked to shorter TST in the third (-0.11, 95% CI -0.20 to -0.27 h) and fourth (-0.16, 95% CI -0.25 to -0.07 h) quartiles. Greater carbohydrate intake was associated with shorter %WASO in the third (-0.82%, 95% CI -1.37% to -0.26%) and fourth (-0.57%, 95% CI -1.13% to -0.01%) quartiles, while greater fat intake was linked to longer %WASO in the fourth quartile (+0.62%, 95% CI 0.06%-1.18%). Dietary fiber intake correlated with longer TST and shorter SL. A greater sodium-to-potassium ratio was associated with shorter TST in the third (-0.11, 95% CI -0.20 to -0.02 h) and fourth (-0.19, 95% CI -0.28 to -0.10 h) quartiles; longer SL in the second (+1.03, 95% CI 0.08-1.98 min) and fourth (+1.50, 95% CI 0.53-2.47 min) quartiles; and longer %WASO in the fourth quartile (0.71%, 95% CI 0.15%-1.28%). Compositional data analysis, involving 6% changes in macronutrient proportions, showed that greater protein intake was associated with an elevated TST (+0.27, 95% CI 0.18-0.35 h), while greater monounsaturated fat intake was associated with a longer SL (+4.6, 95% CI 1.93-7.34 min) and a larger %WASO (+2.2%, 95% CI 0.63%-3.78%). In contrast, greater polyunsaturated fat intake was associated with a reduced TST (-0.22, 95% CI -0.39 to -0.05 h), a shorter SL (-4.7, 95% CI to 6.58 to -2.86 min), and a shorter %WASO (+2.0%, 95% CI -3.08% to -0.92%).

Greater protein and fiber intake were associated with longer TST, while greater fat intake and sodium-to-potassium ratios were linked to shorter TST and longer WASO. Increasing protein intake in place of other nutrients was associated with longer TST, while higher polyunsaturated fat intake improved SL and reduced WASO.

Insomnia is a significant public health problem affecting a large population. Although previous research has explored the relationship between specific nutrients and insomnia, comprehensive analyses of daily eating patterns of macro- and micronutrients remain limited. Since nocturnal hypertension is related to sodium/potassium intake and sleep disturbances, the present cross-sectional study hypothesized that daily eating patterns of potassium and sodium would be associated with Athens Insomnia Scale (AIS) scores.

Dietary data (breakfast, lunch, dinner, and snack intake) and additional online questionnaire responses were obtained from users (N = 4568; age: 43.5 ± 11.2 years) of Asken, a Japanese food-logging mobile health application. AIS scores were divided into three groups according to symptom classification.

Multiple regression analyses revealed that individuals with higher AIS scores had lower daily potassium intake; potassium at dinner was especially crucial.

These results underscore the potential importance of potassium intake in relation to sleep and highlight a novel association between sleep disturbances and the timing of sodium and potassium consumption.

Obesity is a global issue, with over 1.9 billion adults overweight. Disruption of circadian rhythms (CR) leads to obesity and metabolic disorders. Dietary nutrition significantly impacts sleep disorders and disruption in CR, influencing hormones and inflammation, which can contribute to insomnia. The dietary insulin index (DII) and dietary insulin load (DIL) are important factors in determining sleep quality. The current study aims to investigate the association between DII and DIL with CR and sleep quality among with overweight and obesity women.

A case-control study involved 280 overweight/obese women aged 25-40 from Tehran University Medical Science. They were assessed for dietary intake, physical activity, and sleep using validated questionnaires. The study also assessed body composition, bioelectrical impedance analysis, biochemical components, anthropometric components, and blood pressure. Socio-demographic and lifestyle characteristics, such as age, educational level, physical activity, and smoking habits, were also assessed through questionnaires.

In the crude and adjustment models, high adherence of DII compared with lower adherence increased the odds of poor sleep quality index among participants. This significant association remained even after adjustment for confounding variables (P < 0.05), such that the odds of poor sleep quality index was 1.92 times higher.

This study showed high adherence to DII and DIL may cause CR disruption. Furthermore, higher adherence to DII lead to poor sleep quality in women.

To evaluate an association between eating patterns and sleep quality in Chilean university students.

A cross-sectional analytical study was conducted. Participants included students from 4 Chilean universities. Each student was administered survey Questionnaire on the frequency of healthy and unhealthy eating habits and Pittsburgh Sleep Quality Index and their weight and height were taken to obtain the Body Mass Index (BMI).

A total of 1,079 young university students, 80.26 % were women and the average age was 21.7 years. The 73.68 % have inadequate sleep quality. There is a significant differences in frequency between sleep quality and the intake of breakfast (p<0.001), fish (p<0.05) and dinner (p<0.05), that is, university students who reported optimal sleep consume breakfast and dinner on a daily basis and their fish intake is in line with nutritional recommendations. With respect to the association between sleep quality and healthy dietary patterns, it is observed a significant association (p<0.01) between optimal sleep and daily breakfast consumption in model 3 (Odds Ratio (OR): 0.61 (0.46-0.82)). Regarding unhealthy dietary patterns, a significant association (p<0.05) is observed in model 3 between sleep quality and alcohol consumption (OR: 1.42 (1.02-1.96)). Furthermore, a significant association between optimal sleep and salt consumption is observed in both model 2 (OR: 0.73 (0.54-0.99)) and model 3 (OR: 0.72 (0.53-0.97)). Finally, a significant relationship between not tobacco use and optimal sleep is observed (OR: 0.68 (0.48-0.96)).

A positive relationship between healthy diet and sleep quality was observed in university students, which certain dietary patterns, such as the consumption of breakfast and low salt consumption and alcohol, are crucial to talk about a good sleep quality in this population group.

In this study, we aim to examine the impact of dietary total antioxidant capacity (TAC) on sleep problems and depressive symptoms (DS); besides, we seek to elucidate the potential mediating effect of dietary TAC on the relationships between sleep problems and DS.

Weighted Kruskal-Wallis tests for continuous variables and Chi-square tests for categorical variables were employed to discriminate between DS and non-DS participants. Multivariable logistic regression and restricted cubic spline analysis were applied to evaluate the associations of TAC with DS and sleep problems.

Among the 21,805 participants, 1,947 participants suffered from DS. Weighted multivariable logistical regression indicated that shorter sleep hours were linked to an increased likelihood of risk of DS even after complete adjustments. Restricted cubic spline cure displayed that TAC was almost non-linearly correlated with DS and sleep problems. Mediation analysis indicated that sleep duration slightly mediated the association between TAC and DS (proportion of mediation: 3.12%, p < 0.001).

This study illustrated the inverse association between TAC value and sleep problems and DS. Furthermore, TAC slightly mediated the effect of sleep duration on the DS, and there was a nearly non-linear relationship between TAC and DS, and TAC and sleep problems.

This study aimed to assess the association between vitamin D and sleep health and to investigate whether depression could mediate this relationship.

A cross-sectional analysis was performed using the 2005-2014 US National Health and Nutrition Examination Survey (NHANES) data. The logistic regression models were conducted to evaluate association of serum vitamin D concentrations with sleep health and depression. Mediation analyses were conducted to investigate the mediated effects of depression on the association of vitamin D with sleep health.

In multivariate logistic models, vitamin D was found to be negatively associated with an increased risk of poor sleep health, with an odds ratio (OR) of vitamin D deficiency versus sufficiency was 1.256 (95% CI = 1.084-1.455). Additionally, univariate logistic models showed that vitamin D was also negatively associated with depression risk (vitamin D deficiency vs. sufficiency: OR = 1.699, 95% CI = (1.373-2.103). Further mediation analyses showed that the association of vitamin D with sleep health was mediated by depression, with the mediating effects of depression accounted for 44.56% of the total effects.

Vitamin D affects sleep health directly and indirectly through depression. The results suggest that interventions increasing intake of vitamin D should be prioritized to promote sleep health of persons with or at risk of depression.

The symptoms of primary hyperparathyroidism are often subtle, such as fatigue, mood changes, and sleep disturbances. After parathyroidectomy, patients often report improvement in sleep and mood; however, objective data supporting these improvements is lacking.

This prospective study uses standard measures to objectively and subjectively assess sleep in patients with primary hyperparathyroidism before and after parathyroidectomy.

A longitudinal prospective study was conducted over three one-week-long periods: pre-parathyroidectomy, 1-week post-parathyroidectomy, and three months post-parathyroidectomy. During each time point, patients wore an actigraphy device, recorded a sleep diary, and completed the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Depression Anxiety Stress Scale (DASS). Statistical analysis was performed using repeated measures models to compare the average measures among the three time points and test for trends over time.

Single institution, tertiary care center.

Patients with primary hyperparathyroidism from ages 18 to 89 years old.

Parathyroidectomy between September 2020 and January 2024.

Actigraphy data, consensus sleep diary, Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Depression Anxiety Stress Scales - 21 Items (DASS).

Thirty-six patients were enrolled, and 34 patients completed the study. Actigraphy data showed a significant negative trend in average sleep latency (p = 0.045) and average time in bed (p = 0.046). Sleep diary data showed additional differences in the number of awakenings (p = 0.002), wake after sleep onset (p < 0.001), sleep quality (p < 0.001), and sleep efficiency (p = 0.02) among the three time points and/or as a significant negative trend. PSQI and ISI scores were significantly different among the three time points (p = 0.002 and p < 0.001, respectively) and also declined significantly over time (p = 0.008 and p = 0.007, respectively). DASS depression, anxiety, and stress scores were significantly different among the three time points (p < 0.001, p = 0.01, and p < 0.001, respectively), and stress also declined significantly over time (p = 0.005).

This study represents the most extensive prospective study demonstrating objective and subjective sleep and mood improvement in patients with primary hyperparathyroidism after parathyroidectomy.

Arthritis is associated with health challenges. Lifestyle traits are believed to influence arthritis development and progression; however, data to support personalized treatment regimens based on holistic lifestyle factors are missing. This study aims to provide a comprehensive list of associations between lifestyle traits and the health status of individuals with arthritis in the Canadian population, using binary logistic regression analysis on data from the Canadian Community Health Survey, which includes 104,359 respondents. Firstly, we explored the association between arthritis and various aspects of health status including self-reported lifestyle factors. Secondly, we examined the associations between self-reported dietary intake and smoking status with general, mental, and oral health, and sleep disturbance among individuals both with and without arthritis. Our analysis revealed that individuals with arthritis reported considerably poorer general, mental, and oral health, and poorer sleep quality compared to those without arthritis. Associations were also found between self-reported dietary intake and various measures of health status in individuals with arthritis. Smoking and exposure to passive smoking were associated not only with arthritis but also with compromised sleep quality and poorer general, mental, and oral health in people with and without arthritis. This study highlights the need for personalized and holistic approaches that may include a combination of dietary interventions, oral health improvements, sleep therapies, and smoking cessation for improved arthritis prevention and care.

Background: Oxidative stress plays an important role in the occurrence and pathological process of numerous human diseases. A bidirectional relationship was found between sleep disorders and oxidative stress. However, the association between circulating antioxidant levels and the risk of sleep disorders at the population-scale has yet to be determined. Methods: We used the dataset from the National Health and Nutrition Examination Survey (NHANES) 2017-2018 data release cycle and included 3062 adult participants aged 25-75 years. The circulating antioxidants levels in serum were measured, and the sleep status was assessed by self-reported sleep disorder questionnaire tests. We investigated the association and exposure-response relationship between the 12 main circulating antioxidants and sleep disorders using a generalized additive model (GAM), multiple linear, binary logistic, and restricted cubic spline (RCS) regression models. Multiple sensitivity analyses were conducted to validate the results of our study. Results: Significantly lower serum concentrations of ten antioxidants were observed in the group which had trouble sleeping symptoms compared to the control group. After adjusting for all the covariates, the binary logistic regression models indicated that six of the circulating antioxidants including alpha-carotene, alpha-cryptoxanthin, trans-beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin, and vitamin C, showed a significant association with the risk of overall trouble sleeping symptoms, with odds ratios corresponding to 0.88 (95% CI: 0.80-0.96), 0.74 (95% CI: 0.62-0.87), 0.87 (95% CI: 0.79-0.97), 0.85 (95% CI: 0.75-0.95), 0.72 (95% CI: 0.61-0.84), and 0.83 (95% CI: 0.74-0.93), respectively. The GAM and multiple linear regression revealed similar associations whereas the RCS regression models further confirmed their significant negative exposure-response relationship. Conclusions: The circulating carotenoids and vitamin C levels were negatively correlated with the risk of sleep disorders. Higher circulating antioxidant levels were significantly associated with a lower risk of sleep disorders. The potential health risk of low circulating antioxidants levels was higher in the female population than in the male population.

The objective of this study was to examine the association between dietary diversity and sleep quality among Chinese middle-aged and older adults.

The Lifestyle and Healthy Aging of Chinese Square Dancer Study is a prospective, community-based cohort study that enrolled participants aged 45 years and above from 2020 to 2021. Using the semiquantitative food frequency questionnaire to investigate the diets of study participants, and using the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality. Dietary diversity was assessed using two scoring methods covering ten food groups and 66 food items, respectively: the dietary diversity score (DDS) and the food variety score (FVS). The higher scores of DDS and FVS indicated greater dietary diversity and higher dietary quality. Logistic regression analysis explored the associations between these scores and sleep quality.

A total of 2409 individuals with completed information on PSQI and FFQ were included in this study, of whom 767 (31.8%) had poor sleep quality. Participants with higher DDS were associated with an 18% lower odds of poor sleep quality compared to those with low DDS (OR = 0.82, 95% CI, 0.68-0.98). Participants in the highest quartile of the FVS had a 32% lower odds of poor sleep quality than those in the lowest quartile (OR = 0.68, 95% CI, 0.52-0.89).

There was a positive correlation between higher FVS and DDS with better sleep quality. Therefore, ensuring a diverse diet may be beneficial for maintaining good sleep quality among middle-aged and older adults.

Vitamin C is an important micronutrient for human. Association between vitamin C and trouble sleeping was less studied. Therefore, the purpose of this study was to investigate the possible link between vitamin C in serum and trouble sleeping. The cross-sectional data was derived from the National Health and Nutrition Examination Survey (NHANES, 2017-2018). Trouble sleeping was measured by asking participants: "Have you ever told doctor had trouble sleeping". Responses to this question was "yes" or "no". vitamin C in serum was obtained by measuring the serum samples. We used multivariable binary logistic regressions to examine the possible link between vitamin C in serum and trouble sleeping, and then a subgroup analysis was performed. Moreover, the non-linear relationship between vitamin C in serum and trouble sleeping was further detected using a restricted cubic spline (RCS) model. A total of 3227 participants were included in the study. After adjusting all potential confounders, the results of multivariable logistic regression showed the significant negative association between vitamin C in serum and trouble sleeping(OR = 0.816; 95% CI:0.669 ~ 0.995). The significant inverse association was also found in female(OR = 0.713; 95% CI:0.546 ~ 0.931), age ≤ 65 years(OR = 0.773; 95% CI:0.600 ~ 0.996), and in participants with high cholesterol level(OR = 0.738; 95% CI:0.548 ~ 0.994). In addition, the RCS model demonstrated the significant non-linear relationship between vitamin C in serum and trouble sleeping (P value of nonlinear = 0.010). Our study demonstrates the significant negative association between vitamin C in serum and trouble sleeping.

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.

Over the years, there is a rapid increase in the prevalence of inadequate sleep and its detrimental consequences. Yet, the impact of prolonged nutritional interventions on sleep optimization remains unexplored. To examine the effect of carbohydrate manipulation combined with exercise training on sleep macro-structure.

Forty-two healthy, trained male volunteers were recruited for this study. The 4-week intervention consisted of three groups: i) Sleep Low-No Carbohydrates (SL-NCHO): participants consumed all their carbohydrate intake at regular intervals prior to evening training, ii) Sleep High-Low Glycemic Index (SH-LGI) and iii) Sleep High-High Glycemic Index (SH-HGI): Carbohydrate intake was spread throughout the day, both prior (60% of total CHO intake) and after evening training (40% of total CHO intake). The SH-LGI and SH-HGI groups differentiated by consuming either LGI or HGI foods in the evening, respectively. Alongside, participants performed a standardized exercise program combining resistance exercise and high-intensity interval training. Participants' sleep macro-structure was assessed with polysomnography, actigraphy, sleep diary, and sleep-wake questionnaires.

Objective assessments revealed a substantial time-effect on sleep initiation, duration, and continuity. After the intervention, sleep onset latency decreased (p < 0.001), sleep duration was prolonged (p = 0.006), sleep efficiency increased (p < 0.001), and wake after sleep onset decreased (p = 0.035). Sleep macroarchitecture did not significantly change, while the percentage of REM sleep stage to the total sleep time increased over time (p < 0.01). Consistent with the objective findings, subjects reported improved subjective sleep quality (p = 0.043) and reduced daytime sleepiness (p = 0.047).

The combination of a personalized dietary plan with exercise training enhances sleep initiation, sleep continuity, sleep duration, REM and N1 sleep stages, independently of carbohydrate type or timing. Lifestyle interventions should be investigated further to promote sleep quality and recovery.

The trial was registered at clinicaltrials.gov as NCT05464342.

Previous studies have related single essential metal elements (EMEs) to sleep quality among older adults, however, the association of the EME mixture with sleep quality remained poorly understood. This study aimed to investigate the relationships between single EMEs and the EME mixture and sleep quality in older adults living in Chinese communities. This study consisted of 3957 older adults aged 60 years or over. Urinary concentrations of cobalt (Co), vanadium (V), selenium (Se), molybdenum (Mo), strontium (Sr), calcium (Ca), and magnesium (Mg) were detected using inductively coupled plasma mass spectrometry. Sleep quality was evaluated using Pittsburgh Sleep Quality Index (PSQI). The associations of single EMEs and EME mixture with sleep quality were assessed using logistic regression and Bayesian kernel machine regression (BKMR) models, respectively. Adjusted single-element logistic regression models showed that Mo (OR = 0.927, 95%CI:0.867-0.990), Sr (OR = 0.927, 95%CI:0.864-0.994), and Mg (OR = 0.934, 95%CI:0.873-0.997) were negatively related to poor sleep quality. BKMR models exhibited similar results. Also, higher levels of the EME mixture in urine were inversely related to the odds of poor sleep quality after adjustment for covariates, and Mo had the largest conditional posterior inclusion probability (condPIP) value in the mixture. Mo, Sr, and Mg were negatively related to poor sleep quality, separately and as the mixture. The EME mixture in urine was associated with decreased odds of poor sleep quality in older adults, and Mo was the greatest contributor within the mixture. Additional cohort research is warranted to clarify the relationship of multiple EMEs with sleep quality.

Oxidative stress, an imbalance between pro-oxidant and antioxidant status, favouring the pro-oxidant state is a result of increased production of reactive oxygen species (ROS) or inadequate antioxidant protection. ROS are produced through several mechanisms in cells including during mitochondrial oxidative phosphorylation. Increased mitochondrial-derived ROS are associated with mitochondrial dysfunction, an early event in age-related diseases such as Alzheimer's diseases (ADs) and in metabolic disorders including diabetes. AD post-mortem investigations of affected brain regions have shown the accumulation of oxidative damage to macromolecules, and oxidative stress has been considered an important contributor to disease pathology. An increase in oxidative stress, which leads to increased levels of superoxide, hydrogen peroxide and other ROS in a potentially vicious cycle is both causative and a consequence of mitochondrial dysfunction. Mitochondrial dysfunction may be ameliorated by molecules with antioxidant capacities that accumulate in mitochondria such as carotenoids. However, the role of carotenoids in mitigating mitochondrial dysfunction is not fully understood. A better understanding of the role of antioxidants in mitochondrial function is a promising lead towards the development of novel and effective treatment strategies for age-related diseases. This review evaluates and summarises some of the latest developments and insights into the effects of carotenoids on mitochondrial dysfunction with a focus on the antioxidant properties of carotenoids. The mitochondria-protective role of carotenoids may be key in therapeutic strategies and targeting the mitochondria ROS is emerging in drug development for age-related diseases.

Sleep disorder is a growing concern, and calcium supplementation is often recommended as a potential intervention for sleep disorders. However, the causal relationship between calcium levels and the incidence of sleep disorders remains unclear. Mendelian randomization techniques utilizing genetic variants that affect calcium levels, can provide valuable insights into causality. This study aims to examine the association between calcium levels and sleep disorders in a diverse population that includes both adolescents and adults, and investigate the effects of calcium levels on sleep disorders.

Mendelian randomization analysis was conducted using data from UK Biobank and FinnGen datasets. The inverse-variance weighting (IVW) was selected as the primary method. In addition, traditional mediation analysis was performed on a subset of the NHANES data spanning from 2007 to 2018.

Our findings provide evidence supporting a causal relationship between calcium intake and reduced risk of sleep disorders (beta = -0.079, SE = 0.0395, P = 0.0457). While not reaching statistical significance, other MR methods such as weighted median and Mr-Egger exhibited similar directional trends. Analysis of the NHANES cohort revealed a negative association between calcium levels and the prevalence of sleep disorders in male, black, and physically active populations. However, this association was not observed in other demographic groups.

Our results suggested that there is no significant correlation between calcium levels and sleep disorder in non-exercise populations. This raises concerns about the long-term high-dose calcium supplementation in clinical practice, which requires further investigation.

Alzheimer's disease (AD) affects more women than men, with women throughout the menopausal transition potentially being the most under researched and at-risk group. Sleep disruptions, which are an established risk factor for AD, increase in prevalence with normal aging and are exacerbated in women during menopause. Sex differences showing more disrupted sleep patterns and increased AD pathology in women and female animal models have been established in literature, with much emphasis placed on loss of circulating gonadal hormones with age. Interestingly, increases in gonadotropins such as follicle stimulating hormone are emerging to be a major contributor to AD pathogenesis and may also play a role in sleep disruption, perhaps in combination with other lesser studied hormones. Several sleep influencing regions of the brain appear to be affected early in AD progression and some may exhibit sexual dimorphisms that may contribute to increased sleep disruptions in women with age. Additionally, some of the most common sleep disorders, as well as multiple health conditions that impair sleep quality, are more prevalent and more severe in women. These conditions are often comorbid with AD and have bi-directional relationships that contribute synergistically to cognitive decline and neuropathology. The association during aging of increased sleep disruption and sleep disorders, dramatic hormonal changes during and after menopause, and increased AD pathology may be interacting and contributing factors that lead to the increased number of women living with AD.

Poor sleep is associated with numerous adverse health outcomes. Berries are rich in micronutrients and antioxidants that may improve sleep quality and duration. We determined the association of berry consumption and sleep duration and sleep difficulty among adult participants in NHANES.

We analyzed the diet of US adults aged ≥ 20 y using two non-consecutive 24 h recalls from the National Health and Nutrition Examination Survey 2005 to 2018 (N = 29,217). Poor sleep quality was measured by sleep duration (short sleep duration: <7 h), long sleep (≥9 h), and reported sleep difficulty. The relative risk of poor sleep outcomes for berry consumers vs. nonconsumers was modelled using population weight-adjusted multivariable general logistic regression.

About 46% of participants reported inadequate sleep duration, and 27% reported sleep difficulties. Twenty-two percent reported consuming berries. Berry consumers had a 10-17% decreased risk of short sleep. The findings were consistent for specific berry types including strawberries and blueberries (p < 0.05). No significant associations with long sleep were found for total berries and any berry types. A decreased risk of sleep difficulties was found to be linked to blackberry consumption (adjusted OR = 0.63, 95% CI: 0.40-0.97; p = 0.036) but not for other berries.

US adult berry consumers had a decreased risk of reporting short sleep compared to nonconsumers. Berries are underconsumed foods in the US adult population, and increased berry consumption may improve sleep quality.

To investigate the relationship between dietary carotenoid intake and sleep duration.

Adults enrolled in the National Health and Nutrition Examination Survey (NHANES) 2007-2018 without missing information on dietary carotenoid intake (α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein + zeaxanthin), sleep duration, and covariates were included. Participants' carotenoid consumption was divided into three groups by quartiles and sleep duration was grouped as short (< 7 h/night), optimal (7-8 h/night), and long (> 8 h/night). Multinominal logistic regression was constructed to examine the association between dietary carotenoid intake and sleep duration. Restricted cubic spline (RCS) regression was further utilized to explore their dose-response relationship. The weighted quantile sum (WQS) model was adopted to calculate the mixed and individual effect of 5 carotenoid sub-types on sleep duration.

Multinominal logistic regression presented that people with higher intakes of α-carotene, β-carotene, β-cryptoxanthin, lycopene, and lutein + zeaxanthin were less likely to sleep too short or too long. Consistent with the findings from multinominal logistic regression, the RCS models suggested a reverse U-shaped relationship between sleep duration and carotenoid intakes. The mixed effects were also significant, where β-cryptoxanthin and lutein + zeaxanthin were the top 2 contributors associated with the decreased risks of short sleep duration, while β-carotene, α-carotene, and β-cryptoxanthin were the main factors related to the lower risk of long sleep duration.

Our study revealed that the American adults with optimal sleep duration were associated with more dietary carotenoid intake, in comparison to short or long sleepers.

Poor diet can cause sleep disorders; however, this association has not been established in older populations. This study investigated the association between dietary patterns and insomnia symptoms in independent older adults.

This cross-sectional study targeted independent older Japanese adults aged ≥74 years. We used insomnia symptoms classified into three domains: difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and insomnia. These symptoms were assessed as dependent variables by a self-reported questionnaire. Dietary patterns (DP), identified by principal component analysis of a self-administered diet history questionnaire, were used as independent variables. Poisson regression analysis was used to estimate the prevalence ratios and 95% confidence intervals with adjustment for potential confounders.

Among 1,311 participants (mean age = 80.1; women, 48.5%), we identified three dietary patterns: DP1 was characterized by a high intake of vegetables, soy products, and fruits and a low intake of rice; DP2 was characterized by a high intake of fish, chicken, processed meat, and noodles and a low intake of soy products; and DP3 was characterized by a lower intake of fruits and confectionaries. Higher DP1 scores were significantly associated with a lower prevalence of DIS (p-for-trend = 0.012). A higher DP2 score was significantly associated with a higher prevalence of insomnia (p-for-trend = 0.032). There was no significant association between DP3 and insomnia symptoms (p-for-trend >0.05).

Our results highlighted that a dietary pattern with a high intake of vegetables, soy products, and fruits may contribute to reducing insomnia symptoms among independent older adults.

Previous studies have suggested a possible association between metals and sleep disorders. This study aimed to explore the association between Zn, Cu, Se, Mg and Ca and sleep disorders in single and multi-metal co-exposure models.

Logistic regression models, restricted cubic spline model (RCS), Quantile g computation (Q-gcomp), Weighted Quantile Sum (WQS), and Bayesian kernel machine regression (BKMR) models were used to investigate the association between metal levels and sleep disorders.

Logistic regression showed that in the total population, the second, third, and fourth quartile Zn concentration exhibited a lower risk of sleep disorders compared with the first quartile, with odds ratios (ORs) of 0.783, 0.711, and 0.704, respectively. Compared with Zn/Cu and Zn/Se in the first quartile, the third and fourth quartiles showed a lower risk of sleep disorders. In the 30-59 years group, the risk of sleep disorders was 0.699 times greater for the fourth quartile Mg concentration than that for the first quartile. The risk of sleep disorders in Mg/Ca concentration in the third quartile was 0.737 times higher than in the first quartile. Q-gcomp, WQS, and BKMR model analysis showed the negative overall effect of mixtures of the five metals on sleep disorders, with Zn being the largest contributor.

Our study showed that plasma Zn, Mg, Zn/Cu, Zn/Se, and Mg/Ca reduced the risk of sleep disorders, and the combined effect of multiple metals was negatively associated with the risk of sleep disorders, with Zn being the largest contributor to this relationship.

We compared the 24 h changes in interstitial fluid glucose concentration (IGC) following a simulated soccer match between subjects consuming a high-carbohydrate (HCHO; 8 g/kg BW/day) diet and those consuming a moderate-carbohydrate (MCHO; 4 g/kg BW/day) diet. Eight active healthy males participated in two different trials. The subjects were provided with the prescribed diets from days 1 to 3. On day 3, the subjects performed 90 min (2 bouts × 45 min) of exercise simulating a soccer match. The IGC of the upper arm was continuously monitored from days 1 to 4. No significant difference in the IGC was observed between trials during exercise. The total area under the curve (t-AUC) value during exercise did not significantly differ between the HCHO (9719 ± 305 mg/dL·90 min) and MCHO (9991 ± 140 mg/dL·90 min). Serum total ketone body and beta-hydroxybutyrate concentrations were significantly higher in the MCHO than in the HCHO after a second bout of exercise. No significant differences in the IGC were observed between trials at any time point during the night after exercise (0:00-7:00). In addition, t-AUC value during the night did not significantly differ between the HCHO (32,378 ± 873 mg/dL·420 min) and MCHO (31,749 ± 633 mg/dL·420 min). In conclusion, two days of consuming different carbohydrate intake levels did not significantly affect the IGC during a 90 min simulated soccer match. Moreover, the IGC during the night following the exercise did not significantly differ between the two trials despite the different carbohydrate intake levels (8 vs. 4 g/kg BW/day).

We investigated the association between dietary oxidative balance score (DOBS) and mortality and whether this association can be modified by sleep duration.

We calculated DOBS to estimate the overall oxidative effects of the diet, with higher DOBS reflecting more antioxidant intake and less pro-oxidant intake. Cox proportional hazards models were employed to examine the associations between DOBS and all-cause, CVD and cancer mortality in the general population and people with different sleep durations.

Prospective analysis was conducted using data from the US National Health and Nutrition Examination Survey (NHANES, 2005-2015).

A total of 15 991 US adults with complete information on dietary intake, sleep duration and mortality were included.

During a median follow-up of 7·4 years, 1675 deaths were observed. Participants in the highest quartile of DOBS were significantly associated with the lower risk of all-cause mortality (hazard ratio (HR) = 0·75; 95 % CI 0·61, 0·93) compared with those in the lowest. Furthermore, we found statistically significant interactions between DOBS and sleep duration on all-cause mortality (P interaction = 0·021). The inverse association between DOBS and all-cause mortality was significant in short sleepers (HR = 0·66, 95 % CI 0·48, 0·92), but not in normal and long sleepers.

Our study observed that higher DOBS was associated with lower all-cause mortality, and this association appeared to be stronger among short sleepers. This study provides nutritional guidelines for improving health outcomes in adults, especially for short sleepers.

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

A cross-sectional study.

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

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.

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).

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.

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.

Both sodium intake and sleep have an important effect on cardiovascular health. However, few studies have looked at the association between sodium intake and sleep. Therefore, we analysed the association of sodium intake with sleep quality, sleep duration and nocturnal urination. The data for the present study were obtained from the Kangbuk Samsung Health Study. Study participants were 156 696 working-aged Korean adults (average age 38.0 years ±8.0 in men and 36.0 years ±8.1 in women). They were categorised into five groups by quintile of sodium intake, measured by food frequency questionnaire. Poor sleep quality and short sleep duration were determined by Pittsburgh Sleep Quality Index >5, and sleep duration <7 h, respectively. Nocturnal urination was defined as awakening to urinate more than three times a week. Multivariable adjusted logistic regression analysis was used in calculating the odds ratio (OR) and 95% confidence interval (CI) for poor sleep quality, short sleep duration and nocturnal urination (adjusted OR [95% CI]) across five study groups. In all study participants, increased sodium intake was significantly associated with poor sleep quality (quintile 1: reference, quintile 2: 1.07 [1.04-1.11], quintile 3: 1.12 [1.08-1.16], quintile 4: 1.15 [1.11-1.19] and quintile 5: 1.13 [1.09-1.18]). This pattern of relationship was similarly observed in association of sodium intake with short sleep duration (p for trend <0.001) and nocturnal urination (p for trend <0.001). In gender subgroup analysis, increased sodium intake had a significant association with poor sleep quality and short sleep duration in men and with poor sleep quality and nocturnal urination in women. In conclusion, high sodium intake is associated with an increased likelihood of poor sleep quality, short sleep duration and nocturnal urination.

This study was a narrative review of the importance of circadian rhythm (CR), describes the underlying mechanisms of CR in sports performance, emphasizes the reciprocal link between CR, endocrine homeostasis and sex differences, and the unique role of the circadian clock in immune system function and coordination.

As a narrative review study, a comprehensive search was conducted in PubMed, Scopus, and Web of Science (core collection) databases using the keywords "circadian rhythm", "sports performance", "hormonal regulation", "immune system", and "injury prevention". Inclusion criteria were studies published in English and peer-reviewed journals until July 2023. Studies that examined the role of CR in sports performance, hormonal status, immune system function, and injury prevention in athletes were selected for review.

CR is followed by almost all physiological and biochemical activities in the human body. In humans, the superchiasmatic nucleus controls many daily biorhythms under solar time, including the sleep-wake cycle. A body of literature indicates that the peak performance of essential indicators of sports performance is primarily in the afternoon hours, and the evening of actions occurs roughly at the peak of core body temperature. Recent studies have demonstrated that the time of day that exercise is performed affects the achievement of good physical performance. This review also shows various biomarkers of cellular damage in weariness and the underlying mechanisms of diurnal fluctuations. According to the clock, CR can be synchronized with photonic and non-photonic stimuli (i.e., temperature, physical activity, and food intake), and feeding patterns and diet changes can affect CR and redox markers. It also emphasizes the reciprocal links between CR and endocrine homeostasis, the specific role of the circadian clock in coordinating immune system function, and the relationship between circadian clocks and sex differences.

The interaction between insufficient sleep and time of day on performance has been established in this study because it is crucial to balance training, recovery, and sleep duration to attain optimal sports performance.

While dietary intake has previously been related to various indices of poor sleep (e.g., short sleep duration, poor sleep quality), to date, few studies have examined chrononutrition from the perspectives of the relationship between dietary intake and social jet lag and temporal sleep variability. Moreover, recently it has been suggested that previous methods of measuring social jet lag have the potential to lead to large overestimations. Together, this precludes a clear understanding of the role of nutritional composition in the pathophysiology of poor sleep, via social jet lag and temporal sleep variability, or vice versa. The aim of the present study was to determine the relationships between nutrient intake and social jet lag (using a revised index, taking account of intention to sleep and sleep onset and offset difficulties), and temporal sleep variability. Using a cross-sectional survey, 657 healthy participants (mean age 26.7 ± 6.1 years), without sleep disorders, were recruited via an online platform and completed measures of weekly dietary intake, social jet lag, temporal sleep variability, stress/sleep reactivity and mood. Results showed limited associations between nutritional composition and social jet lag. However, levels of temporal sleep variability were predicted by consumption of polyunsaturated fats, sodium, chloride and total energy intake. The results suggest further examinations of specific nutrients are warranted in a first step to tailoring interventions to manage diet and temporal variabilities in sleep patterns.

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.

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.

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).

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.

Poor sleep quality is a common issue among patients with end-stage renal disease (ESRD) who undergo dialysis. Nutritional habits are associated with sleep hygiene in patients undergoing dialysis. The objective of this study was to examine the potential correlation between nutritional status and sleep quality in individuals receiving hemodialysis treatment.

This cross-sectional study included 160 hemodialysis patients. A food frequency questionnaire (FFQ) was used to measure food intake in participants. The Persian-validated version of the Pittsburgh Sleep Quality Index (PSQI) was used to assess sleep quality. Patients were classified as poor or good sleepers with a PSQI score of <5 and >5, respectively.

Eighty-four percent of hemodialysis patients had bad sleep hygiene. There was a significant association between sleep quality and educational status and age (P < 0.001). Poor sleepers were older (61.65 years versus 51.12) and less educated (31.1% versus 4%). However, there was no significant difference in the intake of micro- and macronutrients between poor and good sleepers (P > 0.05).

The results of this study suggest that sleep quality has no significant relationship with nutrient intake in hemodialysis patients. Demographic factors, such as age and educational status, have played a more effective role than nutritional factors in patients' sleep quality.

Sleep difficulties are a common sleep-related problem among children and adolescents. However, the association between eating habits and sleep difficulties has not been extensively studied. Therefore, this study aimed to investigate the relationship between eating habits and sleep difficulties in children and adolescents.

This study utilized cross-sectional data from the 2013/2014 Health Behaviour in School-aged Children survey. A total of 213,879 young adolescents provided self-reported information on their weekday and weekend breakfast consumption, fruit and vegetable intake, sweet and soft drink consumption, and sleep difficulties. Covariates such as sex, age, family affluence, physical activity, and body mass index were also assessed. Multilevel generalized linear modelling was used to analyse the association between independent and dependent. Results were reported as odds ratios (OR) with 95% confidence intervals.

Of all study participants, approximately 50% were girls. Regression models indicated that more frequent breakfast consumption was associated with fewer sleep difficulties (e.g., consuming breakfast on weekdays for 5 days: OR = 1.49, 95% CI: 1.45-1.54). Fruit and vegetable consumption once a week or more was also linked to fewer sleep difficulties (all OR > 1.08, ≥ 1.07). In addition, consuming fewer sweets and soft drinks was generally associated with fewer sleep difficulties.

This study provides evidence supporting the association between healthier eating habits and reduced sleep difficulties in children and adolescents. Future research using longitudinal or experimental designs is encouraged to confirm or negate these findings. Additionally, this study offers practical guidance for nutritional counselling professionals and sleep health promotion practitioners.

Based on nationally representative samples from US, we aimed to assess the associations of vitamins with hearing loss, vision disorder and sleep problem. A total of 25,312, 8425 and 24,234 participants were included in this study to investigate the relationship of vitamins with hearing loss, vision disorder and sleep problem from National Health and Nutrition Examination Survey, respectively. Vitamins including niacin, folic acid, vitamin B6, A, C, E and carotenoids were considered in our study. Logistic regression models were used to assess the associations between all included dietary vitamin intake concentrations and the prevalence of specific outcomes. Increased lycopene (odds ratio [OR]: 0.904, 95% confidence interval [CI]: 0.829-0.985) intake was associated with a deceased prevalence of hearing loss. Higher dietary intake of folic acid (OR: 0.637, 95% CI: 0.443-0.904), vitamin B6 (0.667, 0.465-0.947), alpha-carotene (0.695, 0.494-0.968), beta-carotene (0.703, 0.505-0.969) and lutein + zeaxanthin (0.640, 0.455-0.892) were associated with a decreased prevalence of vision disorder. The inversely associations of sleeping problem with niacin (OR: 0.902, 95% CI: 0.826-0.985), folic acid (0.882, 0.811-0.959), vitamin B6 (0.892, 0.818-0.973), vitamin C (0.908, 0.835-0.987), vitamin E (0.885, 0.813-0.963) and lycopene (0.919, 0.845-0.998) were also observed. Our findings provide evidence that increased specific vitamin intake is associated with decreased prevalence of hearing loss, vision disorder and sleep problem.

Patients with a generalized anxiety disorder (GAD) often report preeminent sleep disturbances. Recently, calcium homeostasis gained interest because of its role in the regulation of sleep-wake rhythms and anxiety symptoms. This cross-sectional study aimed at investigating the association between calcium homeostasis imbalance, anxiety, and quality of sleep in patients with GAD. A total of 211 patients were assessed using the Hamilton Rating Scale for Anxiety (HAM-A), Pittsburgh Sleep Quality Index questionnaire (PSQI) and Insomnia Severity Index (ISI) scales. Calcium, vitamin D, and parathyroid hormone (PTH) levels were evaluated in blood samples. A correlation and linear regression analysis were run to evaluate the association of HAM-A, PSQI, and ISI scores with peripheral markers of calcium homeostasis imbalance. Significant correlations emerged between HAM-A, PSQI, ISI, PTH, and vitamin D. The regression models showed that patients with GAD displaying low levels of vitamin D and higher levels of PTH exhibit a poor subjective quality of sleep and higher levels of anxiety, underpinning higher psychopathological burden. A strong relationship between peripheral biomarkers of calcium homeostasis imbalance, insomnia, poor sleep quality, and anxiety symptomatology was underlined. Future studies could shed light on the causal and temporal relationship between calcium metabolism imbalance, anxiety, and sleep.

Poor sleep quality and insufficient sleep affect a large portion of the population. This is concerning given increasing evidence that poor sleep health is a behavioral risk factor for the development of cardiometabolic diseases. A healthy diet is associated with a plethora of favorable health outcomes, and emerging research now highlights diet as a potential determinant of sleep health that could be leveraged to improve sleep quality. Dairy products are notably rich in tryptophan (Trp), a key substrate for serotonin and melatonin production, which are instrumental for initiating and maintaining sleep. Furthermore, dairy products provide a range of micronutrients that serve as cofactors in the synthesis of melatonin from Trp, which could contribute to sleep-promoting effects. In this review, we evaluate population studies and clinical trials to examine a possible link between dairy consumption and sleep. Available epidemiologic studies illustrate positive associations between dairy intake and sleep outcomes. Moreover, some intervention studies support a causal effect of dairy intake on sleep. Given these data, we discuss potential mechanisms, invite additional clinical research on this topic, and provide insights on how limitations of current studies can be addressed in future trials.

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.

Even though various studies have been conducted to investigate the relationship between trace metals and sleep, few epidemiological studies have evaluated the relationship between trace metals and sleep disorders in American adults.

This study intended to evaluate the associations of serum zinc (Zn), copper (Cu), selenium (Se), Zn/Cu, Zn/Se, and Cu/Se ratios with sleep disorders in American adults.

We conducted a cross-sectional analysis of 3660 adults aged ≥18 years old who participated in the National Health and Nutrition Examination Survey (NHANES) 2011-2016. Binary logistic regression was employed to calculate the odds ratio (OR) and 95 % confidence interval (CI) of either serum trace metals or serum trace metals ratios with risks among sleep disorder phenotypes. The restricted cubic spline (RCS) model was additionally utilized to check the dose-response relationships between serum trace metals, serum trace metals ratios, and sleep disorders.

Logistic regression demonstrated that higher serum Zn (OR: 0.70, 95 % CI: 0.51-0.97, p = 0.035), Zn/Cu (OR: 0.62, 95 % CI: 0.45-0.87, p = 0.007), and Zn/Se (OR: 0.68, 95 % CI: 0.49-0.95, p = 0.025) were related to a decreased likelihood of self-reported sleep disorders, and dose-response relationships were detected by the RCS models, after adjustment for sociodemographic, behavioral, and health characteristics. No associations between serum Cu, Se, Cu/Se, and sleep disorders were observed. The findings in the sensitivity analyses were consistent with these results.

Our study revealed that serum Zn, Zn/Cu, and Zn/Se were inversely associated with the risk of self-reported sleep disorders in US adults.

There is good evidence to indicate severe sleep restriction increases subjective feelings of hunger, but the impact of mild to moderate sleep restriction (i.e., 5-7 h) on hunger has not been systematically evaluated. Healthy male participants (n = 116; 22.8 ± 2.1 years; 22.9 ± 3.7 kg⋅m^-2) were recruited to a ten-day laboratory study. In a between groups design, participants were allocated to one of five time in bed conditions (5 h, 6 h, 7 h, 8 h or 9 h) for seven consecutive nights. Participants were provided a eucaloric diet and ratings of hunger, nausea and desire to eat certain foods were collected using visual analogue scales prior to meals (breakfast, lunch, afternoon snack, dinner and evening snack) on four days during the study. Data were analysed using linear mixed models with time in bed, time of day and study day as fixed effects and participant as a random effect. There was no main effect of time in bed, and no interaction between time in bed and study day, on hunger, nausea, prospective hunger or desire to eat certain foods. However, post-hoc analyses indicated that participants in the 5-h condition had an elevated desire to consume sweet foods and fruit on the final morning of the protocol. There was a main effect of time of day and study day on hunger; participants were hungriest prior to lunch time and hunger decreased over consecutive days of the protocol. When provided with a eucaloric diet, only 5-h time in bed increased desire to consume sweet foods and fruit in healthy young men.

Throughout the course of life, there are age-related changes in sleep. Despite these normal changes, there is a high percentage of older adults that report sleep dissatisfaction with a high pervasiveness of chronic insomnia, the most common sleep disorder worldwide, with its prevalence being expected to continuously increase due to the growing rates of aging and obesity. This can have different adverse health outcomes, especially by promoting both physical and cognitive decline, which ultimately may aggravate frailty in older adults. Moreover, age-related frailty and sleep dysfunction may have a common mechanism related to the hallmarks of cellular aging. Cellular aging was categorized into nine hallmarks, such as DNA damage, telomere attrition and epigenetic changes. In the context of geriatric and chronic insomnia research, this review aims at discussing the current evidence from both animal models and human cohorts addressing the link between chronic insomnia, the hallmarks of aging and their impact on frailty. Moreover, the most recent research about the putative effect of insomnia therapeutic approaches on hallmarks of aging will be also highlighted.

There is sufficient evidence showing that greater sleep quality improves weight loss outcomes achieved through dietary modifications; however, the effects of dietary modifications such as caloric restriction on sleep outcomes is less established. Caloric restriction is a commonly recommended weight-loss method, yet it may result in short-term weight loss and subsequent weight regain, known as "weight cycling", which has recently been shown to be associated with both poor sleep and worse cardiovascular health. The purpose of this brief narrative review was to summarize the evidence from recent studies of the effects of caloric restriction on sleep. Six articles were identified that specifically measured effects of a caloric restriction-based intervention on aspects of sleep as primary or secondary outcomes. Most research to date indicates that caloric restriction improves sleep outcomes including sleep quality and sleep onset latency. However, the relation between caloric restriction and sleep duration is less clear. Given the mixed results and the potential for severe caloric restriction to lead to weight cycling, future studies are needed to clarify how caloric restriction affects sleep and the potential implications for weight-management efforts.

To investigate the association of 24-hour urinary potassium excretion with self-reported sleep quality in the general population.

In this cross-sectional study, a population of patients aged 18 years or older was randomly selected from Xinjiang, China in 2019, 24-hour urine samples collected, and Pittsburgh Sleep Quality Index (PSQI) questionnaires assessed. Participants were divided into 2 groups (upper and lower median of 24-hour urinary potassium excretion). Poor sleep quality was defined as PSQI global score ≥ 6. Associations between 24-hour urinary potassium excretion and [24.8 mmol/L] sleep quality were assessed by multiple logistic regression analysis in total participants and those stratified by sex.

In total, 24-hour urine samples were collected from 1,147 participants, of whom data for those with complete urine samples and PSQI data were analyzed (n = 727; mean age = 48.7 years; percentage of women = 62%). Compared with the upper median group for 24-hour urinary potassium excretion, the lower median group showed a significantly higher PSQI global score (6 vs 5, P = .011), and prevalence of poor sleep quality (51.7% vs 42.2%, P = .011). In a fully-adjusted model of multivariate logistic regression, the lower median group showed 1.50-fold increased odds for presence of poor sleep quality (95% confidence interval: 1.01-2.24, P = .045). Sex-specific analyses translated these results to women, but not to men.

These results suggest that low potassium intake, indicated by lower potassium excretion, is associated with poor sleep quality in the general population, especially among women. Therefore, additional research is necessary to clarify the effect of increasing potassium intake to improve sleep quality.

Li M, Heizhati M, Wang L, et al. 24-hour urinary potassium excretion is negatively associated with self-reported sleep quality in the general population, independently of sleep-disordered breathing. J Clin Sleep Med. 2022;18(11):2589-2596.