Chrono-Nutrition Has Potential in Preventing Age-Related Muscle Loss and Dysfunction

Sleep Duration and Sarcopenia: An Updated Systematic Review and Meta-Analysis

OBJECTIVES

In adults, short and long sleep duration has been associated with sarcopenia risk. Studies have shown that various factors, including biological and psychological factors, could be the underlying cause of the association between aberrant sleep duration and sarcopenia risk. In this study, we have qualitatively and quantitatively summarized previously published studies on sleep duration to assess the relationship between sleep duration and sarcopenia risk in adults. This would aid in enhancing our understanding of recent advancements in this field and the association between sleep duration and sarcopenia risk.

DESIGN

Systematic review and meta-analysis.

SETTING AND PARTICIPANTS

In this review, we included studies evaluating the association between the duration of sleep and sarcopenia in adults in observational studies.

METHODS

Five electronic databases (PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, and Web of Science) were searched to April 20, 2023, to identify studies related to sarcopenia and sleep duration. Next, we calculated the odds ratios (ORs) for sarcopenia prevalence based on the adjusted data from individual studies. Statistical analyses were performed using Stata 11.0.

RESULTS

Sarcopenia prevalence was high (18%) in adults with long sleep duration. Our results showed a significant association between short duration of sleep and high sarcopenia prevalence in older adults (OR 1.2, 95% CI 1.02-1.41, I2 = 56.6%). Furthermore, a significant association was observed between all participants with long-duration sleep and high sarcopenia prevalence (OR 1.53, 95% CI 1.34-1.75, I2 = 56.8%). We also observed significant heterogeneity in the adjusted ORs.

CONCLUSIONS AND IMPLICATIONS

There was a correlation between sarcopenia and short or long sleep duration, especially in older adults. In adults with a long duration of sleep, sarcopenia prevalence was relatively high.

"Diet for the prevention and management of sarcopenia"

Sarcopenia is a geriatric condition characterized by a progressive loss of skeletal muscle mass and strength, with an increased risk of adverse health outcomes (e.g., falls, disability, institutionalization, reduced quality of life, mortality). Pharmacological remedies are currently unavailable for preventing the development of sarcopenia, halting its progression, or impeding its negative health outcomes. The most effective strategies to contrast sarcopenia rely on the adoption of healthier lifestyle behaviors, including adherence to high-quality diets and regular physical activity. In this review, the role of nutrition in the prevention and management of sarcopenia is summarized. Special attention is given to current "blockbuster" dietary regimes and agents used to counteract age-related muscle wasting, together with their putative mechanisms of action. Issues related to the design and implementation of effective nutritional strategies are discussed, with a focus on unanswered questions on the most appropriate timing of nutritional interventions to preserve muscle health and function into old age. A brief description is also provided on new technologies that can facilitate the development and implementation of personalized nutrition plans to contrast sarcopenia.

Effect of Circadian Rhythm Disturbance on the Human Musculoskeletal System and the Importance of Nutritional Strategies

The circadian system in the human body responds to daily environmental changes to optimise behaviour according to the biological clock and also influences various physiological processes. The suprachiasmatic nuclei are located in the anterior hypothalamus of the brain, and they synchronise to the 24 h light/dark cycle. Human physiological functions are highly dependent on the regulation of the internal circadian clock. Skeletal muscles comprise the largest collection of peripheral clocks in the human body. Both central and peripheral clocks regulate the interaction between the musculoskeletal system and energy metabolism. The skeletal muscle circadian clock plays a vital role in lipid and glucose metabolism. The pathogenesis of osteoporosis is related to an alteration in the circadian rhythm. In the present review, we discuss the disturbance of the circadian rhythm and its resultant effect on the musculoskeletal system. We also discuss the nutritional strategies that are potentially effective in maintaining the system's homeostasis. Active collaborations between nutritionists and physiologists in the field of chronobiological and chrononutrition will further clarify these interactions. This review may be necessary for successful interventions in reducing morbidity and mortality resulting from musculoskeletal disturbances.

Is There a Utility of Chrono-Specific Diets in Improving Cardiometabolic Health?

Modern lifestyle is generally associated with the consumption of three main meals per day, one of which is typically in the evening or at night. It is also well established that consumption of meals in the later part of the day, notably in the evenings, is associated with circadian desynchrony, which in turn increases the risk of non-communicable diseases, particularly cardiometabolic diseases. While it is not feasible to avoid food consumption during the evenings altogether, there is an opportunity to provide chrono-specific, diet-based solutions to mitigate some of these risks. To date, there has been substantial progress in the understanding of chrononutrition, with evidence derived mainly from in vitro and in vivo animal studies. Some of these approaches include the manipulation of the quality and quantity of certain nutrients to be consumed at specific times of the day, as well as incorporating certain dietary components (macronutrients, micronutrients, or non-nutrient bioactives, including polyphenols) with the ability to modulate circadian rhythmicity. However, robust human studies are generally lacking. In this review, the study has consolidated and critically appraised the current evidence base, with an aim to translate these findings to improve cardiometabolic health and provides recommendations to move this field forward.

Relationship Between Protein Intake in Each Traditional Meal and Physical Activity: Cross-sectional Study

Background

Protein intake plays an important role in the synthesis and maintenance of skeletal muscles for the prevention of health risks. It is also widely known that physical activity influences muscle function. However, no large-scale studies have examined the relationship between daily dietary habits, especially the timing of protein intake, and daily physical activity.

Objective

The purpose of this cross-sectional study was to investigate how protein intake and composition (involving the 3 major nutrients protein, fat, and carbohydrate) in the 3 traditional meals (breakfast, lunch, and dinner) are associated with physical activity.

Methods

Using daily dietary data accumulated in the smartphone food log app “Asken” and a web-based cross-sectional survey involving Asken users (N=8458), we analyzed nutrient intake and composition, as well as daily activity levels. As very few individuals skipped breakfast (1102/19,319 responses, 5.7%), we analyzed data for 3 meals per day.

Results

Spearman rank correlation analysis revealed that breakfast and lunch protein intakes had higher positive correlations with daily physical activity among the 3 major macronutrients (P<.001). These findings were confirmed by multivariate logistic regression analysis with confounding factors. Moreover, participants with higher protein intake and composition at breakfast or lunch tended to exhibit significantly greater physical activity than those with higher protein intake at dinner (P<.001).

Conclusions

Among the 3 macronutrients, protein intake during breakfast and lunch was closely associated with daily physical activity.

Circadian Synchrony: Sleep, Nutrition, and Physical Activity

The circadian clock in mammals regulates the sleep/wake cycle and many associated behavioral and physiological processes. The cellular clock mechanism involves a transcriptional negative feedback loop that gives rise to circadian rhythms in gene expression with an approximately 24-h periodicity. To maintain system robustness, clocks throughout the body must be synchronized and their functions coordinated. In mammals, the master clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN is entrained to the light/dark cycle through photic signal transduction and subsequent induction of core clock gene expression. The SCN in turn relays the time-of-day information to clocks in peripheral tissues. While the SCN is highly responsive to photic cues, peripheral clocks are more sensitive to non-photic resetting cues such as nutrients, body temperature, and neuroendocrine hormones. For example, feeding/fasting and physical activity can entrain peripheral clocks through signaling pathways and subsequent regulation of core clock genes and proteins. As such, timing of food intake and physical activity matters. In an ideal world, the sleep/wake and feeding/fasting cycles are synchronized to the light/dark cycle. However, asynchronous environmental cues, such as those experienced by shift workers and frequent travelers, often lead to misalignment between the master and peripheral clocks. Emerging evidence suggests that the resulting circadian disruption is associated with various diseases and chronic conditions that cause further circadian desynchrony and accelerate disease progression. In this review, we discuss how sleep, nutrition, and physical activity synchronize circadian clocks and how chronomedicine may offer novel strategies for disease intervention.

Circadian Synchrony: Sleep, Nutrition, and Physical Activity

The circadian clock in mammals regulates the sleep/wake cycle and many associated behavioral and physiological processes. The cellular clock mechanism involves a transcriptional negative feedback loop that gives rise to circadian rhythms in gene expression with an approximately 24-h periodicity. To maintain system robustness, clocks throughout the body must be synchronized and their functions coordinated. In mammals, the master clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN is entrained to the light/dark cycle through photic signal transduction and subsequent induction of core clock gene expression. The SCN in turn relays the time-of-day information to clocks in peripheral tissues. While the SCN is highly responsive to photic cues, peripheral clocks are more sensitive to non-photic resetting cues such as nutrients, body temperature, and neuroendocrine hormones. For example, feeding/fasting and physical activity can entrain peripheral clocks through signaling pathways and subsequent regulation of core clock genes and proteins. As such, timing of food intake and physical activity matters. In an ideal world, the sleep/wake and feeding/fasting cycles are synchronized to the light/dark cycle. However, asynchronous environmental cues, such as those experienced by shift workers and frequent travelers, often lead to misalignment between the master and peripheral clocks. Emerging evidence suggests that the resulting circadian disruption is associated with various diseases and chronic conditions that cause further circadian desynchrony and accelerate disease progression. In this review, we discuss how sleep, nutrition, and physical activity synchronize circadian clocks and how chronomedicine may offer novel strategies for disease intervention.