Association between Breakfast Skipping and the Metabolic Syndrome: The Korea National Health and Nutrition Examination Survey, 2017

Effect of breakfast protein intake on muscle mass and strength in adults: a scoping review

BACKGROUND

The distribution of protein intake throughout the day is frequently skewed, with breakfast having the lowest protein intake across all age groups. There is no review that addresses the association between breakfast protein intake and muscle mass and strength.

OBJECTIVE

This scoping review aims to summarize the literature on the relationship between protein intake during breakfast and muscle mass and strength in adults.

METHODS

This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. Two independent reviewers screened and appraised the articles identified from 3 electronic databases (Medline, Web of Science, and Scopus) that focused on protein intake per meal and its impact on muscle-related outcomes.

RESULTS

A total of 14 763 articles were retrieved from 3 databases, and after the screening process, 15 articles were included for analysis. Approximately 58.8% of findings from 11 studies examining the association between high protein intake during breakfast and muscle mass indicated an increase in muscle mass among participants. Half of 6 studies (50.0%) exploring the relationship between high protein intake at breakfast and muscle strength demonstrated an increase in muscle strength. Consuming high amounts of protein at breakfast or more protein in the morning than in the evening was associated with an increase in the skeletal muscle index and lean body mass.

CONCLUSION

Protein consumption at breakfast revealed potential benefits in increasing muscle mass across 5 studies involving an elderly population and 2 studies encompassing middle-aged women and young men in our review. However, the relationship between protein intake at breakfast and muscle strength remains unclear. Further high-quality randomized controlled trials are required to examine whether adults can preserve skeletal muscle health outcomes by consuming higher amounts of protein at breakfast.

Circadian Deregulation: Back Facing the Sun Toward Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) Development

Earth's rotation around its axis has pressured its inhabitants to adapt to 24 h cycles of day and night. Humans adapted their own circadian rhythms to the Earth's rhythms with a light-aligned awake-sleep cycle. As a consequence, metabolism undergoes drastic changes throughout the circadian cycle and needs plasticity to cope with opposing conditions in the day (when there is an increase in energy demands and food availability), and during the night (when prolonged fasting couples with cyclic changes in the energy demands across the sleep stages). In the last century, human behavior changed dramatically with a disregard for the natural circadian cycles. This misalignment in sleep and eating schedules strongly modulates the metabolism and energy homeostasis, favoring the development of obesity, metabolic syndrome, and metabolic dysfunction-associated steatotic liver disease (MASLD). This review summarizes the effects of circadian disruption, with a particular focus on the feeding and sleep cycles in the development of MASLD and hepatocellular carcinoma.

Dietary Intake, Menopausal Symptoms, and Body Composition Associated with Possible Sarcopenia Among Vietnamese Middle-Aged Women: A Cross-Sectional Study

Background: This study aims to investigate the prevalence of possible sarcopenia and its associated factors among middle-aged Vietnamese women. Methods: A cross-sectional study was conducted on 205 women aged 40-55 years who were admitted to the Can Tho Obstetrics and Gynecology Hospital between February and December 2023. The presence of possible sarcopenia was determined according to the AWGS 2019 criteria. Associated factors were dietary intake (total energy, protein, lipid, and carbohydrate intake), the severity of menopausal symptoms by using the Kupperman index, and body composition by using the bioelectrical impedance analysis device, Inbody S10. Logistic regressions were built to analyze the association between possible sarcopenia and its associated factors. Results: The prevalence of possible sarcopenia was 29.8%, with a mean age of 47.2. Possible sarcopenia was detected in 23% of the participants based on the criterion of low handgrip strength, whereas 83.6% of the participants when considered low performance in the chair stand test. Adjusted logistic regression analysis showed that living in a rural area (adjusted odds ratio [AOR]: 2.16, 95% confidence interval [95% CI]: 1.22-4.72), energy intake <25 kcal/body weight, (AOR: 1.94, 95% CI: 1.75-5.06), protein intake <0.91 g/body weight (AOR: 2.42, 95% CI: 1.51-5.76), skipping breakfast (AOR: 2.03, 95% CI: 0.91-4.54), mild menopausal symptoms (AOR: 2.68, 95% CI: 1.61-5.36), and obesity (AOR: 1.59, 95% CI: 1.29-3.67) were significantly associated with higher risk of possible sarcopenia. Conversely, higher muscle mass and higher upper limb mass were associated with a decreased risk of possible sarcopenia (total muscle mass AOR: 0.20, 95% CI: 0.07-0.59). Conclusions: These findings would provide a basis for enhancing management and prevention strategies to reduce the risk of sarcopenia in Vietnam. In particular, attention to nutrient intake and the management of menopausal symptoms may reduce the risk of sarcopenia.

Chrononutrition and Cardiometabolic Health: An Overview of Epidemiological Evidence and Key Future Research Directions

Chrononutrition is a rapidly evolving field of nutritional epidemiology that addresses the complex relationship between temporal eating patterns, circadian rhythms, and metabolic health, but most prior research has focused on the cardiometabolic consequences of time-restricted feeding and intermittent fasting. The purpose of this topical review is to summarize epidemiological evidence from observational and intervention studies regarding the role of chrononutrition metrics related to eating timing and regularity in cardiometabolic health preservation and cardiovascular disease prevention. Observational studies are limited due to the lack of time-stamped diet data in most population-based studies. Findings from cohort studies generally indicate that breakfast skipping or the later timing of the first eating occasion, a later lunch and dinner, and a greater proportion of caloric intake consumed in the evening are associated with adverse cardiometabolic outcomes, including higher risk for coronary heart disease, hypertension, type 2 diabetes, obesity, dyslipidemia, and systemic inflammation. Randomized controlled trials are also limited, as most in the field of chrononutrition focus on the cardiometabolic consequences of time-restricted feeding. Overall, interventions that shift eating timing patterns to earlier in the day and that restrict evening caloric intake tend to have protective effects on cardiometabolic health, but small sample sizes and short follow-up are notable limitations. Innovation in dietary assessment approaches, to develop low-cost validated tools with acceptable participant burden that reliably capture chrononutrition metrics, is needed for advancing observational evidence. Culturally responsive pragmatic intervention studies with sufficiently large and representative samples are needed to understand the impact of fixed and earlier eating timing schedules on cardiometabolic health. Additional research is warranted to understand the modifiable determinants of temporal eating patterns, to investigate the role of chrononutrition in the context of other dimensions of diet (quantity, quality, and food and nutrition security) in achieving cardiometabolic health equity, and to elucidate underlying physiological mechanisms.

Scoping review: Exploring the relationship between chrononutrition and glycemic responses in the adult population

Chrononutrition, an emerging body of evidence on the relationship between biological rhythms and metabolism, has been established to be associated with glycemic responses. However, the available evidence is inconsistent, due to protocol variations. Therefore, this review aims to summarize the findings on chrononutrition characteristics and their association with glycemic responses among adults. Systematic searches were conducted across six databases (PubMed, EBSCO Host, ProQuest Central, MEDLINE & Ovid, Scopus and Web of Science) to identify all relevant studies published from January 2012. Two reviewers independently screened the abstracts and full-text articles based on the inclusion and exclusion criteria. Details about population characteristics, study methods and key findings were extracted following the PRISMA-ScR guideline. The quality of selected studies was evaluated using the mixed methods appraisal tool. The searchers identified 49 studies eligible for analysis. The results showed that meal timing, particularly night-time eating and snacking were associated with glycemic responses. Regarding meal regularity, skipping breakfast may affect glycemic responses, but no clear conclusion was drawn about its effect on insulin. The association between meal frequency and glycemic responses was inconclusive. Night fasting duration and restricted eating window are potentially associated with glycemic responses. The current review extensively investigates the association between chrononutrition factors and glycemic responses in adults. However, more prospective cohort and interventional studies are needed to better understand this causal-effect relationship.

Unfavorable Mealtime, Meal Skipping, and Shiftwork Are Associated with Circadian Syndrome in Adults Participating in NHANES 2005-2016

The concept of Circadian Syndrome (CircS) aims to emphasize the circadian disruptions underlying cardiometabolic conditions. Meal timing and shiftwork may disrupt circadian rhythms, increasing cardiometabolic risk. This study aimed to assess the associations of meal timing, meal skipping, and shiftwork with CircS in US adults and explore effect modifications by sociodemographic and lifestyle factors. CircS was defined using Metabolic Syndrome components in addition to short sleep and depression symptoms. Data from 10,486 participants of the National Health and Nutrition Examination Survey 2005-2016 were analyzed cross-sectionally. Mealtime was assessed by calculating the midpoint of intake between breakfast and dinner and dichotomizing it into favorable mealtime (between 12:30 and 13:15) and unfavorable mealtime using a data-driven approach. Meal skippers were categorized separately. Participants working evening, night, or rotating shifts were classified as shift workers. In the multivariable logistic regression analysis, an unfavorable mealtime, meal skipping, and shiftwork were associated with a higher likelihood of CircS (OR = 1.24; 95%CI 1.07-1.44, OR = 1.39; 95%CI 1.16-1.67, and OR = 1.37; 95%CI 1.01-1.87, respectively). Subgroup analyses revealed no significant interactions between meal timing, meal skipping, or shiftwork and socioeconomic status or lifestyle regarding CircS. These findings highlight the importance of aligning mealtimes with circadian rhythms for improved circadian health.

Eating patterns in Korean adults, 1998-2018: increased energy contribution of ultra-processed foods in main meals and snacks

PURPOSE

Unfavorable changes in eating patterns over time may contribute to upward trends in chronic diseases, such as obesity. We examined 20-year trends in the percentage of energy from main meals and snacks and the food sources of each eating occasion among Korean adults.

METHODS

This study used nationally representative data from the 1st, 4th, and 7th Korea National Health and Nutrition Examination Surveys (1998, 2007-2009, and 2016-2018) among adults aged 20-69 years (n = 29,389). Each eating occasion (breakfast, lunch, dinner, and snacks) was defined by respondents during a 24-h dietary recall interview. To identify the food sources of each eating occasion, we used the NOVA system. The percentage of energy at each eating occasion and that from each NOVA group across survey cycles were estimated, and tests for linear trends were conducted using orthogonal polynomial contrasts in linear regression models. All analyses accounted for the complex survey design.

RESULTS

After adjusting for age and sex, the percentage of energy from breakfast decreased from 25.0% in 1998 to 16.7% in 2018 (difference, - 8.2%; standard error [SE], 0.3), whereas that from dinner and snacks increased from 31.1 to 33.8% (difference, + 2.7%; SE, 0.4) and from 14.0 to 19.0% (difference, + 5.0%; SE, 0.5), respectively (all P < 0.001). At all eating occasions, the percentage of energy from minimally processed foods declined (difference, - 18.6% for breakfast; - 13.1% for lunch; - 21.1% for dinner; - 20.7% for snacks), while that from ultra-processed foods increased (difference, + 17.0% for breakfast; + 11.3% for lunch; + 18.0% for dinner; + 30.7% for snacks). When stratified by age, the given trends were shown to a greater extent in younger adults (< 50 years old) than in older adults (≥ 50 years old).

CONCLUSIONS

The eating patterns of Korean adults changed from 1998 to 2018, with the greatest decrease in energy intake from breakfast and the greatest increase from snacking. At all eating occasions, the contribution of minimally processed foods declined, while that of ultra-processed foods increased, especially among younger adults.

Association between breakfast frequency and metabolic syndrome among young adults in South Korea

Skipping breakfast is highly prevalent but it is not clear whether breakfast frequency is associated with metabolic syndrome in young adults. We aimed to assess the association between breakfast frequency and metabolic syndrome in Korean young adults. This cross-sectional study was based on health check-up data of university students aged 18-39 years between 2016 and 2018. Participants were stratified into three groups by breakfast frequency (non-skipper, skipper 1-3 days/week, skipper 4-7 days/week). Multivariable-adjusted logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of metabolic syndrome. Out of 12,302 participants, 56.8% skipped breakfast at least 4 days/week. Metabolic syndrome prevalence was higher in those skipping breakfast for 4 or more days/week compared to non-skipper. (3.1% vs 1.7%) In the age- and sex-adjusted model, individuals skipping breakfast for 4-7 days per week had a higher OR of metabolic syndrome (OR 1.73, 95% CI 1.21-2.49) compared to non-skipper. Although this association became insignificant (OR 1.49, 95% CI 0.99-2.23) after a fully adjusted multivariable model, trends of positive association between frequency of breakfast skipping and metabolic syndrome was significant (P for trend = 0.038). Frequent breakfast skipping was associated with higher odds of metabolic syndrome in young adults. Further longitudinal studies in the long term are needed to understand the association of meal patterns with metabolic syndrome.

Breakfast Practices in Malaysia, Nutrient Intake and Diet Quality: A Study Based on the Malaysian Food Barometer

Breakfast is often referred to as the "most important meal of the day" in shaping diet quality. This study established the patterns of breakfast consumption in Malaysia and assessed its contribution to the overall quality of the diet based on the 24 h recall data from the nationally representative and cross-sectional Malaysian Food Barometer (MFB, second data collection, 2018) to assess breakfast intake among adults (n = 1604). Diet quality was measured using the Nutrient Rich Food index (NRF) 9.3. The nutritional profile of breakfast was compared across tertiles of NRF 9.3. Overall, 89% of Malaysians consume breakfast. Breakfast was found to provide 474 kcal on average. The Malaysian daily diet was found to be rich in fats, saturated fats, total sugars, and sodium, with breakfast making a significant contribution to the daily intakes of these nutrients. Intakes of fiber, potassium, calcium, vitamins C and D, folate, iron, zinc, and magnesium were low. Breakfast was related to the overall diet quality measured by the NRF index. This study revealed that the breakfasts consumed by Malaysian adults were found to be nutritionally unbalanced. This analysis could serve as a basis for nutrient recommendations grounded in existing social and cultural breakfast patterns.

Intermittent Fasting Is Associated With a Decreased Risk of Age-Related Macular Degeneration

PURPOSE

To investigate the association between intermittent fasting and age-related macular degeneration (AMD) in the general older adult population.

DESIGN

A cross-sectional study using a population-based, government-led survey data, Korean National Health and Nutrition Examination Survey (KNHANES).

METHODS

A total of 4504 individuals aged ≥55 years with comprehensive data including meal frequency and fundus photography were selected using the KNHANES 2015-2018 database. Participants were divided into 2 groups based on breakfast frequency per week; intermittent fasting (nearly 0 time/week) and nonfasting (5-7 times/week) groups. Multiple logistic regression analysis was performed to determine the risk factors for AMD identified by fundus photography.

RESULTS

AMD was identified in 25.1% of total participants. The intermittent fasting group had a decreased risk of AMD compared with the nonfasting group (adjusted odds ratio [aOR] 0.413, 95% CI 0.203-0.841), especially in individuals with a younger age (<70 years, aOR 0.357, 95% CI 0.153-0.833), obesity (aOR 0.663, 95% CI 0.424-1.037), and urban residence (aOR 0.437, 95% CI 0.248-0.769). Increased age (aOR 1.058, 95% CI 1.041-1.076) and serum high-density lipoprotein levels (aOR 1.011, 95% CI 1.002-1.021) were also independent risk factors for AMD.

CONCLUSIONS

Using the population-based survey data, we demonstrated that intermittent fasting by skipping breakfast was significantly associated with a reduced risk of AMD in a representative older adult population, especially in individuals with age <70 years, obesity, and urban residence.

Lifestyle Factors Associated with Metabolic Syndrome in Urban Cambodia

This study aimed to identify lifestyle factors associated with metabolic syndrome (MetS) in urban Cambodia. In this cross-sectional study, we used existing health checkup data from a private hospital in Phnom Penh, Cambodia. The participants comprised 5459 Cambodians aged ≥20 years who underwent health checkups between 2017 and 2019. The harmonized diagnostic definition was used as the MetS criteria. The prevalence of MetS was 56.6% overall, 60.4% in men and 52.6% in women. The lifestyle factor significantly associated with MetS in both sexes were "eating quicker than others", (men: odds ratio [OR]= 2.25, 95% confidence interval [CI] = 1.68-3.03, women: OR = 1.92, 95%CI = 1.41-2.60), "walking faster than others", (men: OR = 0.78, 95% CI = 0.67-0.92, women: OR = 0.75, 95% CI = 0.62-0.89) and "drinking alcohol" (men: OR = 1.33, 95% CI = 1.10-1.61, women: OR = 1.33, 95% CI = 1.09-1.62). Other significant associations with MetS for men was "eating speed is normal", (OR = 1.73, 95%CI = 1.30-2.31), and, for women, "eating food after dinner at least 3 days a week", (OR = 1.25, 95%CI = 1.01-1.55), "skipping breakfast at least 3 days a week", (OR = 0.83, 95%CI = 0.69-0.99) and "getting enough rest from sleep" (OR = 1.19, 95% CI = 1.01-1.42) were significantly associated with MetS. Lifestyle interventions through health education and guidance may be effective in preventing MetS in Cambodia.

Hydration and meal habits of physicians and medical learners: a literature review

PURPOSE

Nutrition and hydration are important components of physician and medical learner well-being; meal-skipping and insufficient hydration are known to negatively impact cognition. Existing data on these phenomena are sparse and rarely considered together; furthermore, there is a lack of literature on interventions to address these problems. We therefore aimed to characterize existing literature on this topic.

METHODS

We conducted a literature review of existing literature on the prevalence of and reasons for meal-skipping and insufficient hydration in physicians and medical learners.

RESULTS

Reported prevalences varied widely, as did the ways in which the data were collected. Reasons for meal-skipping and insufficient hydration are less studied, but a lack of time is the most commonly reported reason, among a variety of other barriers.

CONCLUSION

Further research is required to better characterize the prevalences and reasons for meal-skipping in physicians and medical learners. By consolidating the state of current knowledge on this topic in this work, we establish the groundwork for future studies and allow intervention studies to be based on a broader data set.

Association of Coffee Consumption and Its Types According to Addition of Sugar and Creamer with Metabolic Syndrome Incidence in a Korean Population from the Health Examinees (HEXA) Study

Coffee is widely consumed worldwide, and numerous studies indicate that coffee consumption may potentially affect the development of chronic diseases. Metabolic syndrome (MetS) may constitute a risk factor for chronic diseases. We aimed to prospectively evaluate the association between coffee consumption and MetS incidence. All participants were selected from the Health Examinees study. MetS was defined by the Adult Treatment Panel III criteria of the National Cholesterol Education Program. A multivariate Cox proportional hazards regression model was used to assess the relationship between coffee consumption and MetS incidence. In comparison with non-consumers, male moderate consumers (≤3 cups/day) showed a lower risk for low high-density lipoprotein cholesterol (HDL-C) (≤1 cup/day, hazard ratio (HR): 0.445, 95% confidence interval (CI): 0.254-0.780; 1-3 cups/day, HR: 0.507, 95% CI: 0.299-0.859) and high fasting blood glucose (FPG) (≤1 cup/day, HR: 0.694, 95% CI: 0.538-0.895; 1-3 cups/day, HR: 0.763, 95% CI: 0.598-0.972). Male 3-in-1 coffee (coffee with sugar and creamer) consumers also showed a lower risk for low HDL-C (HR: 0.423, 95% CI: 0.218-0.824) and high FPG (HR: 0.659, 95% CI: 0.497-0.874). These findings indicate a negative association between moderate coffee consumption and low HDL-C and high FPG among Korean male adults.

Association between breakfast skipping and metabolic outcomes by sex, age, and work status stratification

BACKGROUND

The association between breakfast skipping and abnormal metabolic outcomes remains controversial. A comprehensive study with various stratified data is required.

OBJECTIVE

The aim of this study was to investigate the relationship between abnormal metabolic outcomes and breakfast skipping by sex, age, and work status stratification.

METHODS

We used data from the Korea National Health and Nutrition Examination Surveys from 2013 to 2018. A total of 21,193 (9022 men and 12,171 women) participants were included in the final analysis. The risk of metabolic outcomes linked to breakfast skipping was estimated using the negative binomial regression analysis by sex, work status, and age stratification.

RESULTS

A total of 11,952 (56.4%) participants consumed breakfast regularly. The prevalence of abnormal metabolic outcomes was higher among those with irregular breakfast consumption habits. Among young male workers, negative binomial regression analysis showed that irregular breakfast eaters had a higher risk of abnormal metabolic outcomes, after adjusting for covariates (odds ratio, 1.15; 95% confidence interval, 1.03-1.27).

CONCLUSIONS

The risk of abnormal metabolic outcomes was significant in young men in the working population. Further studies are required to understand the association of specific working conditions (working hours or shift work) with breakfast intake status and the risk of metabolic diseases.

Unexpectedly High Prevalence of Breakfast Skipping in Low Body-Weight Middle-Aged Men: Results of the Kanagawa Investigation of Total Checkup Data from the National Data Base-7 (KITCHEN-7)

Breakfast skipping (BS) has been considered to be associated with obesity, particularly among younger generations. However, few studies have addressed this issue in a middle-aged population considering sex and the conditions prior to breakfast. Therefore, we investigated clinical parameters, self-reported BS, late-night dinner (LND) eating, and late-night snacking (LNS) in ten body mass index (BMI) categories in a cross-sectional study of 892,578 non-diabetic people aged 40-74 years old who underwent a checkup. BS and LND were more prevalent in men (20.7% and 40.5%, respectively) than women (10.9% and 17.4%), whereas LNS was more prevalent in women (15.0%) than men (12.2%; all p < 0.0001). The overall prevalence of BS increased linearly with increasing BMI. However, when subjects were divided into men and women, the prevalence of BS showed a U-shaped relationship with BMI in men (n = 479,203). When male subjects were restricted to those in their 40s or those reporting LND, the prevalence of BS further increased, maintaining a U-shaped form. Logistic regression analysis also showed a U-shaped relationship in the adjusted odds ratios of BMI categories for BS in men and a J-shaped curve in women. In conclusion, our study revealed an unexpectedly high prevalence of BS in middle-aged low-body-weight men.