Major dietary patterns in relation to obesity and quality of sleep among female university students

Associations between body mass index and physical fitness indicators among Chinese university students: a multicenter cross-sectional study

BACKGROUND

Increasing body mass index (BMI) has many negative effects on the physical and mental health of university students and has become a common public health problem in all countries. However, there are few studies on the association between BMI and physical fitness indicators among Chinese university students in developing countries, and the findings are inconsistent. The present study aims to analyze the association between BMI and physical fitness indicators among Chinese university students, to assist in university students' health development and intervention.

METHODS

In this study, we conducted a cross-sectional assessment of BMI of 29,371 university students and a cross-sectional assessment of physical fitness indicators of vital capacity, sit and reach, pull-up(boys), sit-up(girls), standing long jump, 50 m dash, 1000 m run(boys ), 800 m run(girls). One-way analysis of variance (ANOVA), Pearson's correlation analysis, and nonlinear regression modeling were used to analyze the associations that existed between BMI and various physical fitness indicators.

RESULTS

The percentages of Chinese university students in emaciated, normal, overweight, and obese were 17.8%, 65.3%, 14.9%, and 2.0%, respectively. Comparing between different BMI groups (emaciated, normal, overweight, and obesity), for boys, the effect values ranged from 1.0 to 2.0% for the items of vital capacity, sit and reach, pull-up/situp, standing long jump, 50 m dash, and 1000/800 m-run. For run events, the range of effect sizes ranged from 0.2 to 0.9; the range of effect sizes for girls also ranged from 0.2 to 0.9.

CONCLUSIONS

The physical fitness level of emaciated and obese Chinese university students is generally lower than that of normal-weight students, and the relationship between BMI and physical fitness indicators shows a "U-shape" or "inverted U-shape" curve. The effect of BMI on physical fitness is more significant in boys than in university girls. In the future, targeted physical exercise and health education should be provided to emaciated and obese university students to maintain a reasonable body weight and promote the healthy development of physical fitness.

The association of dietary inflammatory index with sleep outcomes: A systematic review

Background

Sleep is a vital physiological process that plays a crucial role in various aspects of human health and well-being. Regarding the important role of diet on the sleep quality, the present study aimed to assess the association of dietary inflammatory index (DII) with the sleep outcomes and also to provide the potential mechanisms of action.

Methods

PubMed, Web of Science and Scopus databases and Google Scholar search engine were systematically searched for relevant studies related to DII and sleep outcomes using appropriate search terms until February 2024.

Results

From the initial systematic search of databases, 197 studies were retrieved. However, only 14 of them met the criteria for evaluation. Out of these, eleven studies indicated a significant correlation between higher DII scores and poor overall sleep quality and/or short/long sleep duration or its subscales. On the contrary, four studies did not find any proof of this association.

Conclusion

This systematic review indicated that following an anti-inflammatory diet could potentially lead to an improvement in the sleep outcomes. Well-designed clinical trials in the future will be necessary to provide a better understanding and quantification of this association.

Adherence to the Mediterranean Diet in Women and Reproductive Health across the Lifespan: A Narrative Review

The Mediterranean diet (MD) has been previously proven to have various health-related benefits; however, its effect on women's reproductive health over a lifespan is yet to be summarized. This study aimed to summarize the evidence-based knowledge regarding the association between the MD and selected reproductive health outcomes. By searching PubMed, ScienceDirect, and Google Scholar databases, as well as reference lists, 21 studies were included in this narrative review. The available evidence was very limited; however, there is some suggestion that higher adherence to the MD may be positively associated with a lower risk of early age menarche (1 study) and shorter menstrual cycles (1 study), but is unrelated to dysmenorrhea (1 study). Moreover, no study to date has examined the relationship between the MD and the onset age of natural menopause. Considering reproductive health diseases, there was limited evidence that a higher adherence to the MD was associated with a lower risk of premenstrual syndrome (1 study), an improvement in sexual health and a lower prevalence of sexual dysfunction (3 studies), and an improvement in the general condition of with endometriosis and the pain they can experience (1 study). The largest number of studies were found for polycystic ovarian syndrome (PCOS; 7 studies) and infertility (6 studies). Results showed that a higher adherence to the MD was associated with a lower risk of infertility, while results for PCOS were unclear, but mostly indicated a beneficial trend. Further investigations are necessary to establish the role of adherence to the MD in reproductive health maintenance and its possible role in the prevention and treatment of reproductive health diseases in women.

Intake of ultra-processed foods and sleep-related outcomes: A systematic review and meta-analysis

The aim of this review article was to evaluate the association between the intake of ultra-processed foods and sleep-related outcomes through a systematic review and meta-analysis. Pubmed, LILACS, Scielo, Scopus, Embase, and Web of Science were searched on December 31, 2021, for studies that evaluated the association between ultra-processed foods and sleep-related outcomes (self-reported sleep duration and quality). Pooled odds ratios were assessed through a random-effects model; heterogeneity was evaluated using the I² statistic. Fifteen cross-sectional studies were included; 14 showed that the high intake of ultra-processed foods was statistically significantly associated with sleep-related outcomes (sleep duration and quality). In the crude analysis, compared with low intake, high intake of ultra-processed foods increased the odds of sleep-related outcomes, with increased odds among children and/or adolescents, and null results among adults. When adjusted for cofounders, we found statistically significant results for all ages. The high intake of ultra-processed foods was associated with sleep-related outcomes, with moderate credibility of the evidence. Longitudinal studies and clinical trials confirming these findings are necessary.

Dietary pattern changes, obesity and excess body fat in adults of a Brazilian birth cohort

BACKGROUND

Few studies have assessed dietary patterns (DPs) and the changes in these patterns over time in adults. The present study aimed to investigate whether possible changes in DPs in two assessments are associated with obesity and excess body fat.

METHODS

A prospective study was conducted in which data were collected from 1082 adults of a Brazilian birth cohort during two periods 15 years apart (T1: 2002-2004; T2: 2016-2017). Food consumption was assessed in both periods using validated food frequency questionnaires. Three similar DPs were found in the two assessments, and adherence to these patterns was classified as prudent, risk or mixed. Nine DPs changes were defined. At T2, subjects with a body mass index ≥ 30.0 kg m^- ² were classified as obese, and men and women with a body fat (BF) percentage ≥ 25.0 and ≥ 35.0, respectively, were classified as having excess BF. A directed acyclic graph was built to adjust the association for confounding variables.

RESULTS

At T2, 34.4% of the subjects were obese and 61.4% had excess BF. In the adjusted analysis, the changes associated with obesity and excess BF were prudent-mixed (prevalence ratio [PR] 1.55; 95% confidence interval [CI] = 1.04-2.29 and PR = 1.35; 95% CI = 1.10-1.65), risk-risk (PR = 1.49; 95% CI = 1.03-2.13 and PR = 1.27; 95% CI = 1.04-1.53), risk-mixed (PR = 1.56; 95% CI = 1.05-2.31 and PR = 1.33; 95% CI = 1.07-1.63) and mixed-risk (PR = 1.61; 95% CI = 1.10-2.35 and PR = 1.29; 95% CI = 1.04-1.58).

CONCLUSIONS

A decline in food quality over time or stagnation in an unhealthy DP can lead to obesity and excess BF.

Association of healthy beverage index with circadian rhythm and quality of sleep among overweight and obese women: a cross-sectional study

PURPOSE

Circadian rhythm is a behavioral, physiological, and molecular change with a cycle length of approximately 24 h. Changes to the circadian rhythm can result in sleep difficulty. The healthy beverage index (HBI) is a holistic concept for evaluating the quality of overall beverage intake and its association with health-related outcomes in nutritional epidemiological studies. This study aimed to assess the relationship of HBI with circadian rhythm and sleep quality among overweight/obese women.

METHODS

The current study was conducted among 208 overweight and obese women between 18-48 years in Tehran, Iran. We evaluated potential HBI with a valid food frequency questionnaire. Following standard procedures, trained personnel assessed anthropometric measures, blood samples, and other baseline characteristics. The Pittsburgh Sleep Quality Index and the morning-eveningness questionnaire were applied to evaluate sleep quality and circadian rhythm respectively.

RESULTS

The mean (SD) BMI for this study was 30.8 (4.2) kg/m². We observed that subjects in the least tertile had significantly high levels of triglyceride (p = 0.04) and low-density lipoprotein (p = 0.009). High-density lipoprotein was significantly different across the tertiles (p = 0.003). After adjusting for potential covariates, subjects in the second tertile of HBI had 5.07 odds of having the worst quality of sleep as compared to those in the third tertile, p < 0.05. We also observed a significant inverse association between the HBI and the "moderately evening type" participants (OR 0.86; 95% CI 0.68-0.99; p: 0.02) after adjusting for potential confounders.

CONCLUSION

Healthy beverage consumption may have the potential of improving sleep quality among overweight and obese subjects.

LEVEL OF EVIDENCE

Level IV, evidence obtained from a descriptive study.

The relationship between dietary patterns and sleep disorders in shift workers

BACKGROUND: Few studies have been done on the association of dietary intakes with sleep disorders among shift workers, in particular those exposed to air pollution. OBJECTIVE: We aimed to investigate the association of major dietary patterns with risk of sleep disorders in shift workers of a cement factory. METHODS: This cross-sectional study was carried out on 257 male shift workers in a cement factory in Iran. Usual dietary intake of participants was assessed using a validated self-administrated 147-item dish-based food frequency questionnaire. To examine sleep disturbances of participants, we used the Epworth Sleepiness Scale. RESULTS: Three major dietary patterns including Classic Iranian, Modern Iranian, and High Protein Low Fruit and vegetables were identified. The Classic Iranian pattern was mainly consisted of high-protein animal foods, fruit, and vegetables, while the Modern Iranian pattern had high amounts of refined grains, solid oils, and caffeine drinks. No significant association was found between adherence to the Classic Iranian pattern and risk of sleep disorders (OR: 2.33; 95% CI: 0.69, 7.81) and also for the Modern Iranian dietary pattern (OR: 0.62; 95% CI: 0.20, 1.93). However, we found a significant direct association between the High Protein Low Fruit and vegetables dietary pattern and risk of sleep disorders (OR: 3.92; 95% CI: 1.03, 14.86). CONCLUSIONS: This study showed a significant direct association between a dietary pattern high in animal proteins and solid oils and low in fruit and vegetables with risk of sleep disorders among shift workers in the cement factory. However, no such association was found for the two other dietary patterns.

The association between modified Nordic diet with sleep quality and circadian rhythm in overweight and obese woman: a cross-sectional study

OBJECTIVE

Previous studies have shown an association between diet quality and sleep quality. The objective of this study was to investigate the association between modified Nordic diet with sleep quality and circadian rhythm in overweight and obese woman.

METHODS

We enrolled 399 overweight and obese women (body mass index (BMI): 25-40 kg/m²), aged 18-48 years, in this cross-sectional study. For each participant, anthropometric measurements, biochemical tests, and food intake were evaluated. Sleep quality and circadian rhythm was measured by Pittsburgh Sleep Quality Index (PSQI) and morning-evening questionnaire (MEQ) questionnaire. Modified Nordic diet score was measured using a validated 147-item food frequency questionnaire (FFQ).

RESULTS

Overall, 51.7% of the subjects were good sleepers (the Pittsburgh Sleep Quality Index (PSQI) < 5) while 48.3% were poor sleepers (PSQI ≥ 5). Moreover, participants were divided into five groups of MEQ, namely, completely morning 8 (2.4%), rarely morning 82 (24.8%), normal 196 (59.2%), rarely evening 43 (13%), and completely evening 2 (0.6%). After controlling for confounders, there was a significant association between poor sleep quality and the modified Nordic diet (OR = 0.80, %95 CI = 0.66-0.98, P = 0.01). Moreover, a significant positive association was observed between the completely morning and modified Nordic diet (OR = 1.80, %95 CI = 0.54-6.00, P = 0.03), in addition to a significant inverse association between the completely evening type and modified Nordic diet (OR = 0.16, %95 CI = 0.002-5.41, P = 0.02).

CONCLUSIONS

The present study indicated that higher adherence to a modified Nordic diet reduces poor sleep quality. Also, the completely morning type was associated with higher adherence to a modified Nordic diet, and completely evening type was associated with lower adherence to a modified Nordic diet.

LEVELS OF EVIDENCE

Level IV, evidence obtained from multiple time series analysis.