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Changes in objectively measured sleep after a multidisciplinary lifestyle intervention in children with abdominal obesity: A randomized trial.
Catalán-Lambán, A, Ojeda-Rodríguez, A, Marti Del Moral, A, Azcona-Sanjulian, C
Sleep medicine. 2023;109:252-260
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The main factors that contribute to obesity are genetics, excessive energy intake, decreased physical activity, and sedentarism. Sleep duration, sleep timing and chronotype have also recently been recognised as possible risk factors for obesity in children. The aim of this study was to assess the effectiveness of an intervention (usual care vs. intervention group) on sleep quality and its relationship with changes in biochemical and metabolic syndrome related anthropometric parameters. This study was a randomised controlled trial. The multidisciplinary intervention consisted of a two-year program that comprised a 2-month intensive phase with individual and group sessions and a follow-up period at 12 and 24 months. Subjects were randomly assigned to the usual care or intervention group at a ratio of 1:3. Results showed that a lifestyle intervention improved most sleep parameters in children and adolescents with abdominal obesity. In fact, the lifestyle intervention showed a reduction in anthropometric indexes and several biochemical parameters, and improved sleep quality at 2, 12, and 24 months of follow-up. Decreasing sleep latency, awakenings duration and wakefulness after sleep onset (WASO) also accompanied improved sleep efficiency. Authors conclude that their findings add to the growing body of research on the relationship between sleep and metabolic health outcomes in children, emphasizing the need to consider multiple dimensions of sleep beyond just sleep duration.
Abstract
BACKGROUND/OBJECTIVE childhood obesity and sleep disorders have a well-established cross-sectional association, but lifestyle interventions' effects on sleep quality remain under-researched. This study aimed to evaluate the sleep quality of 122 participants (7-16 years) with abdominal obesity after a 2-year necessary lifestyle intervention. PATIENTS/METHODS participants were assigned to either the intervention group (moderate hypocaloric Mediterranean Diet) or the usual care group (standard recommendations on a healthy diet). Sleep was objectively assessed using triaxial accelerometry, and sleep parameters analyzed included latency, efficiency, wake after sleep onset, total time in bed, total sleep time, number of awakenings, and awakening duration. RESULTS AND CONCLUSIONS the results showed that the intervention group significantly improved sleep latency at 12 and 24 months and improved sleep efficiency at 2 and 12 months, compared to the usual care group. Wake after sleep onset and the number of awakenings were significantly reduced at 24 months in the intervention group. Wake after sleep onset and leptin levels were positively associated in all participants. Total time in bed was inversely associated with triglycerides and metabolic score, and total sleep time was inversely associated with leptin, triglycerides, and metabolic score after the 2-month intervention. Triglyceride levels were inversely associated with total time in bed and total sleep time at one year, while the metabolic score was directly associated with wake after sleep onset and the number of awakenings and inversely associated with efficiency. In conclusion, the multidisciplinary intervention in children and adolescents with abdominal obesity reduced anthropometric parameters and improved sleep habits.
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Probiotic intervention benefits multiple neural behaviors in older adults with mild cognitive impairment.
Fei, Y, Wang, R, Lu, J, Peng, S, Yang, S, Wang, Y, Zheng, K, Li, R, Lin, L, Li, M
Geriatric nursing (New York, N.Y.). 2023;51:167-175
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Mild cognitive impairment (MCI) is an intermediate stage between the normal cognitive changes associated with aging and dementia. Recent research shows that probiotic supplementation can regulate the balance of the intestinal flora and improve self-care ability and cognition in older adults. The aim of this study was to explore the effects and the underlying mechanisms of probiotic supplementation on MCI older adults. This study was a pilot randomised controlled trial (RCT) to investigate the effects of 12 weeks of probiotic supplementation in patients with MCI. Participants were randomly assigned to the probiotic group or control group. Results demonstrated the beneficial effects of probiotic supplementation intervention on multiple neural behaviours by regulating the homeostasis of the gut microbiota in older MCI patients. Authors conclude that this study provided new insights into nutrition interventions in older MCI patients. However, further trials with larger cohorts should be conducted to confirm the effects of probiotic intervention in MCI patients and provide more clinical evidence for its preventive and therapeutic effects.
Abstract
Probiotic supplements were shown to improve cognitive function in Alzheimer's disease (AD) patients. However, it is still unclear whether this applies to older individuals with mild cognitive impairment (MCI). We aimed to explore the effects of probiotic supplementation on multiple neural behaviors in older adults with MCI. Forty-two MCI patients (age > 60 years) were randomly divided into two groups and consumed either probiotics (n=21) or placebo (n=21) for 12 weeks. Various scale scores, gut microbiota measures and serological indicators were recorded pre- and posttreatment. After 12 weeks of intervention, cognitive function and sleep quality were improved in the probiotic group compared with those in the control group, and the underlying mechanisms were associated with changes in the intestinal microbiota. In conclusion, our study demonstrated that probiotic treatment enhanced cognitive function and sleep quality in older MCI patients, thus providing important insights into the clinical prevention and treatment of MCI.
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Attitudes and adherence to changes in nutrition and physical activity following surgery for prostate cancer: a qualitative study.
Robles, LA, Shingler, E, McGeagh, L, Rowe, E, Koupparis, A, Bahl, A, Shiridzinomwa, C, Persad, R, Martin, RM, Lane, JA
BMJ open. 2022;12(6):e055566
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Prostate cancer is a leading cancer in men from the United Kingdom. Diet and exercise are recommended for men with prostate cancer however, few achieve the recommendations. Psychological and behavioural factors are often responsible for the lack of change and this qualitative study aimed to determine the most common, with a view to helping individuals to affect change. The results showed that several men believed that diet and physical activity had no association with cancer and those who did, maintained a healthy diet and took regular exercise. Most men thought they had a good diet before diagnosis, however evidence for this was mixed. Barriers to change were plentiful and included physical inability, taste of food, and side effects of supplements. It was concluded that behaviour change models could help with adherence to a better diet and exercise regime. This study could be used by healthcare professionals to understand that it may not be enough to simply recommend diet and exercise to men with prostate cancer. Support and guidance may also be needed.
Abstract
OBJECTIVES Interventions designed to improve men's diet and physical activity (PA) have been recommended as methods of cancer prevention. However, little is known about specific factors that support men's adherence to these health behaviour changes, which could inform theory-led diet and PA interventions. We aimed to explore these factors in men following prostatectomy for prostate cancer (PCa). DESIGN, SETTING AND PARTICIPANTS A qualitative study using semistructured interviews with men, who made changes to their diet and/or PA as part of a factorial randomised controlled trial conducted at a single hospital in South West England. Participants were 17 men aged 66 years, diagnosed with localised PCa and underwent prostatectomy. Interview transcripts underwent thematic analysis. RESULTS Men were ambivalent about the relationship of nutrition and PA with PCa risk. They believed their diet and level of PA were reasonable before being randomised to their interventions. Men identified several barriers and facilitators to performing these new behaviours. Barriers included tolerance to dietary changes, PA limitations and external obstacles. Facilitators included partner involvement in diet, habit formation and brisk walking as an individual activity. Men discussed positive effects associated with brisk walking, such as feeling healthier, but not with nutrition interventions. CONCLUSIONS The facilitators to behaviour change suggest that adherence to trial interventions can be supported using well-established behaviour change models. Future studies may benefit from theory-based interventions to support adherence to diet and PA behaviour changes in men diagnosed with PCa.
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Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle interventions: secondary analyses of the "MIMOSA" randomized clinical trial.
Georgoulis, M, Yiannakouris, N, Kechribari, I, Lamprou, K, Perraki, E, Vagiakis, E, Kontogianni, MD
Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine. 2022;18(5):1251-1261
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Obstructive sleep apnoea (OSA) represents one of the most common and serious sleep-related breathing disorders. Excess body weight has emerged as the strongest modifiable predictor of the onset and severity of OSA. The aim of this study was to explore the dose-response relationship between the degree of weight loss and improvements in OSA severity. This study is a secondary analysis of the Mediterranean diet/lifestyle Intervention for the Management of Obstructive Sleep Apnea (MIMOSA) study, which was designed as a single-centre, single-blind, parallel, randomised, controlled clinical trial. Results show that respiratory events and oximetry indices improved only in patients who lost weight and improvements were proportional to the degree of weight loss. Authors conclude that their findings indicate a dose-response relationship between the degree of weight loss and improvement in OSA severity and symptoms. However, further research is needed to gather more data on the optimal degree of weight loss and appropriate weight-loss interventions for managing the wide spectrum of OSA severity to guide clinical practice.
Expert Review
Conflicts of interest:
None
Take Home Message:
Important from a public health perspective:
- This study has confirmed that even a small degree of weight loss can have a beneficial effect on respiratory events and oxygen desaturation in moderate-to-severe OSA, but clinicians should preferably aim at a ≥ 5% weight loss, and ideally a ≥ 10% weight loss, to achieve clinically meaningful reductions in OSA severity.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
OSA represents one of the most common and serious sleep-related breathing disorders, with a high worldwide prevalence of almost 1 billion people. OSA has numerous well-established cardiometabolic consequences.
The authors highlight that weight loss is essential for obstructive sleep apnea (OSA) management. However, the optimal degree of weight loss for improving OSA severity or eliminating sleep-disordered breathing has not been extensively studied. The aim of this study was to explore the dose-response relationship between the degree of weight loss and improvements in OSA severity.
Methods
This is a secondary analysis of the Mediterranean diet/lifestyle Intervention for the Management of Obstructive Sleep Apnea (MIMOSA) study. This study was designed as a single-center, single-blind, parallel, randomised, controlled clinical trial to evaluate the effectiveness of a weight-loss Mediterranean dietary/lifestyle intervention on managing OSA.
This 6-month long clinical trial included 180 adult, overweight/obese moderate-to-severe OSA patients (45 patients per study group plus a 29% dropout rate). All patients were prescribed the standard of care continuous positive airway pressure (CPAP) therapy and were randomised to 3 arms: standard care; Mediterranean diet; Mediterranean lifestyle
Based on percent change in weight at 6 months, participants were categorised into a weight-stable/gain (WS/GG) group or one of 3 weight-loss groups (WLG): < 5%WLG; 5%–10%WLG; ≥ 10%WLG. Polysomnographic data and OSA symptoms were also evaluated preintervention and postintervention.
Results
Results confirm a dose-response relationship between the degree of weight loss achieved through a dietary/lifestyle intervention and improvements in OSA severity.
- Respiratory events and oximetry indices improved only in patients who lost weight. Improvements were proportional to the degree of weight loss.
- Median percent change in apnea-hypopnea index (AHI) was −11.7%, − 37.9%, and − 49.3% in the < 5%WLG, 5%–10%WLG, and ≥ 10%WLG, respectively (P < .001).
- Compared to the WS/GG, the age-, sex-, baseline-, and CPAP use–adjusted relative risk (95% confidence interval) of severe OSA (AHI ≥ 30 events/h) was 0.45 (0.23–0.87) in the 5%–10%WLG and 0.32 (0.17–0.64) in the ≥ 10%WLG; the risk was also lower in the ≥ 10%WLG vs the < 5%WLG (0.42 [0.22–0.82]).
- Insomnia and daytime sleepiness also improved more in participants exhibiting ≥ 5% weight loss.
- The dose-response relationship between weight loss and improvement in OSA severity was evident regardless of self-reported CPAP use.
Conclusions
The authors conclude that even a < 5% weight loss was sufficient for improvements in respiratory events and oximetry indices, but the prevalence of severe OSA reduced only after a ≥ 5% weight loss, and patients achieving a ≥ 10% weight loss exhibited the greatest benefits compared to weight-stable/gain patients.
Clinical practice applications:
These findings might be useful for Nutritional Therapists and Clinical Practitioners:
- Clinicians should aim for a ≥ 5% weight loss, and ideally a ≥ 10% weight loss, to achieve clinically meaningful reductions in OSA severity.
- Improvements after weight loss were significant even though a healthy body weight was not achieved.
Considerations for future research:
- The study sample consisted of predominantly male, overweight, otherwise healthy patients with moderate-to-severe OSA. Therefore, findings cannot be generalised to the whole OSA population and further research is required with broader, diverse, study samples.
- 6 months is a short duration period, therefore longer trials are required.
- Self-reported CPAP use by participants is a limitation of this study. Further robust analysis methods should be considered for future trials.
- Participants were advised to abstain from CPAP therapy for 2 days prior to the follow-up PSG but this was not evaluated or confirmed in this study and should be in future research.
Abstract
STUDY OBJECTIVES Lifestyle-induced weight loss is a complementary therapeutic approach for obstructive sleep apnea (OSA). We aimed at identifying the dose-response relationship between weight loss and OSA severity improvement. METHODS This is a secondary analysis of a 6-month clinical trial in 180 adult, overweight/obese moderate-to-severe OSA patients. Participants were randomized to a standard care, a Mediterranean diet, or a Mediterranean lifestyle arm. All patients were prescribed with continuous positive airway pressure (CPAP), while intervention arms additionally participated in a weight-loss dietary/lifestyle intervention. Based on percent change in weight at 6 months, participants were categorized into a weight-stable/gain (WS/GG) group or 3 weight-loss groups (WLG): < 5%WLG, 5%-10%WLG, and ≥ 10%WLG. Polysomnographic data and OSA symptoms were evaluated preintervention and postintervention. RESULTS Respiratory events and oximetry indices improved only in patients who lost weight and improvements were proportional to the degree of weight loss. Median percent change in apnea-hypopnea index (AHI) was -11.7%, - 37.9%, and - 49.3% in the < 5%WLG, 5%-10%WLG, and ≥ 10%WLG, respectively (P < .001). Compared to the WS/GG, the age-, sex-, baseline-, and CPAP use-adjusted relative risk (95% confidence interval) of severe OSA (AHI ≥ 30 events/h) was 0.45 (0.23-0.87) in the 5%-10%WLG and 0.32 (0.17-0.64) in the ≥ 10%WLG; the risk was also lower in the ≥ 10%WLG vs the < 5%WLG (0.42 [0.22-0.82]). Insomnia and daytime sleepiness also improved more in participants exhibiting ≥ 5% weight loss. CONCLUSIONS Even a < 5% weight loss can reduce respiratory events, but a ≥ 5% and ideally ≥ 10% weight loss is necessary for reducing the prevalence of severe OSA. CLINICAL TRIAL REGISTRATION Registry: ClinicalTrials.gov; Name: Mediterranean Diet/Lifestyle Intervention in Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT02515357; Identifier: NCT02515357. CITATION Georgoulis M, Yiannakouris N, Kechribari I, et al. Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle intervention: secondary analyses of the "MIMOSA" randomized clinical trial. J Clin Sleep Med. 2022;18(5):1251-1261.
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Development and Effects of College-Based Lifestyle Modification Program for Menstrual Health of Young Adult Women with Irregular Menses: A Randomized Controlled Trial.
Park, YJ, Shin, H, Jeon, S, Cho, I, Park, HJ
International journal of environmental research and public health. 2020;18(1)
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Irregular menstruation is characterized by abnormal uterine bleeding, unpredictable menstrual volume, and irregularity of menstruation. A regular menstrual cycle demonstrates a normal sex hormone profile and functioning of reproductive organs, whereas irregularity may suggest a dysfunctional sex hormone profile or disorder of reproductive organs. This study is a randomised controlled trial intended to develop a College-based Lifestyle Modification Programme (LMP) to improve the menstrual health of young adult women who experienced irregular menstruation less than ten times a year, and its effects on their health. The study has two arms: intervention and control group. Female participants (n=46) were randomly assigned 1:1 to one of the two groups. Results show that the College-based LMP had positive effects on the alleviation of depression and anxiety, and improvement of sleep duration. Whereas there were no significant differences for certain variables (menstrual cycle index, sex hormone binding globulin, testosterone, free androgen index), overall premenstrual syndrome, menstrual volume, body composition parameters, and nutrient intake. Authors conclude that their findings demonstrated the importance of lifestyle modifications, which could provide ordinary young adult women with healthy menstruation. However, further studies with the use of supplements are required to address the limitations of the current study.
Abstract
Purpose: This study was conducted to develop the 'College-based Lifestyle Modification Program' (College-based LMP) for young adult women with irregular menstruation and examine its effects after intervention. Methods: The College-based LMP consisted of small group education, individual physical exercise counseling/training, individual diet counseling, and feedback and support. Participants were comprised of 38 females who reported less than 10 irregular menstruations in a year and were randomly assigned to the experimental and control groups. The primary outcome variables consisted of menstrual cycle index (MCI), sex hormone binding globulin (SHBG), and androgenic profile (testosterone-T, free androgen index-FAI), while the outcome variables included premenstrual symptoms (PMS), menstrual volume, body composition parameters, glycemic parameters (fasting blood sugar-FBS, insulin, HOMA-IR), sleep duration, perceived stress, and nutrient intake.. Results: There were no significant differences in primary outcome variables (MCI, SHBG, T, and FAI). In the variables, there were no significant differences except for the partial domain of PMS (symptoms of depression and anxiety) and sleep duration. Conclusions: The study was significant in that it demonstrated the importance of lifestyle, which could provide ordinary young adult women with healthy menstruation. The College-based LMP needs to be elaborated with further studies.
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Circadian Rhythms, Metabolism, and Chrononutrition in Rodents and Humans.
Johnston, JD, Ordovás, JM, Scheer, FA, Turek, FW
Advances in nutrition (Bethesda, Md.). 2016;7(2):399-406
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Chrononutrition is an emerging field that links the body’s metabolism to its endogenous circadian rhythm. It is now recognised that numerous circadian clocks are found within all major tissues and most cells of the body. This complex network of clocks influences a wide range of biological processes including neuronal, endocrine, metabolic and behavioural function. When there is a disruption in a single circadian clock, whole-organism homeostasis can be impacted, potentially resulting in the development of disease. This review explains the potential mechanisms by which circadian clocks influence biological processes through transgenic animal studies, and how they are being translated to human genetics and metabolomics. The principles of chrononutrition are clinically significant factors that should be considered when managing and treating metabolic disease, as well as maintaining health in the general population.
Abstract
Chrononutrition is an emerging discipline that builds on the intimate relation between endogenous circadian (24-h) rhythms and metabolism. Circadian regulation of metabolic function can be observed from the level of intracellular biochemistry to whole-organism physiology and even postprandial responses. Recent work has elucidated the metabolic roles of circadian clocks in key metabolic tissues, including liver, pancreas, white adipose, and skeletal muscle. For example, tissue-specific clock disruption in a single peripheral organ can cause obesity or disruption of whole-organism glucose homeostasis. This review explains mechanistic insights gained from transgenic animal studies and how these data are being translated into the study of human genetics and physiology. The principles of chrononutrition have already been demonstrated to improve human weight loss and are likely to benefit the health of individuals with metabolic disease, as well as of the general population.
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Multiple risk-behavior profiles of smokers with serious mental illness and motivation for change.
Prochaska, JJ, Fromont, SC, Delucchi, K, Young-Wolff, KC, Benowitz, NL, Hall, S, Bonas, T, Hall, SM
Health psychology : official journal of the Division of Health Psychology, American Psychological Association. 2014;33(12):1518-29
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Individuals with serious mental illness (SMI) are at greater risk for chronic disease, which are largely preventable through health behaviour change. Within this population tobacco use is a major health concern and recent trials have demonstrated treating tobacco dependence supports mental health recovery. As risk behaviours tend to co-occur, the aim of this study was to examine the behavioural risk profiles of adult smokers with SMI to further understand frequencies and patterns of risks in order to best inform interventional programmes. In the context of a tobacco-treatment trial, 693 adult smokers from inpatient psychiatry wards were recruited. The Staging Health Risk Assessment was used which screens for risk status and readiness to change 11 health behaviours. The findings of this study showed that most smokers with SMI engage in multiple risks including poor diet, inadequate sleep, physical inactivity and marijuana use. This study can help prioritise health intervention programme targets and provide further benefit for this population.
Abstract
OBJECTIVE Individuals with serious mental illness (SMI) are dying on average 25 years prematurely. The leading causes are chronic preventable diseases. In the context of a tobacco-treatment trial, this exploratory study examined the behavioral risk profiles of adults with SMI to identify broader interventional needs. METHOD Recruited from five acute inpatient psychiatry units, participants were 693 adult smokers (recruitment rate = 76%, 50% male, 45% Caucasian, age M = 39, 49% had income < $10,000) diagnosed with mood disorders (71%), substance-use disorders (63%), posttraumatic stress disorder (39%), psychotic disorders (25%), and attention deficit-hyperactivity disorder (25%). The Staging Health Risk Assessment, the primary measure used in this study, screened for risk status and readiness to change 11 health behaviors, referencing the period prior to acute hospitalization. RESULTS Participants averaged 5.2 (SD = 2.1) risk behaviors, including smoking (100%), high-fat diet (68%), inadequate fruits/vegetables (67%), poor sleep (53%), physical inactivity (52%), and marijuana use (46%). The percent prepared to change ranged from 23% for tobacco and marijuana to 76% for depression management. Latent class analysis differentiated three risk groups: the global higher risk group included patients elevated on all risk behaviors; the global lower risk group was low on all risks; and a mood and metabolic risk group, characterized by inactivity, unhealthy diet, sleep problems, and poor stress and depression management. The global higher risk group (11% of sample) was younger, largely male, and had the greatest number of risk behaviors and mental health diagnoses; had the most severe psychopathologies, addiction-treatment histories, and nicotine dependence; and the lowest confidence for quitting smoking and commitment to abstinence. CONCLUSION Most smokers with SMI engaged in multiple risks. Expanding targets to treat co-occurring risks and personalizing treatment to individuals' multibehavioral profiles may increase intervention relevance, interest, and impact on health.
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Timing of food intake predicts weight loss effectiveness.
Garaulet, M, Gómez-Abellán, P, Alburquerque-Béjar, JJ, Lee, YC, Ordovás, JM, Scheer, FA
International journal of obesity (2005). 2013;37(4):604-11
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As obesity is a multifactorial disease, dietary interventions must take into account a range of physiological and psychological variables. There is emerging evidence linking energy regulation to the circadian clock, emphasizing that the timing of eating may play a role in weight regulation. The aim of this study was to evaluate the role of food timing in weight loss effectiveness among 420 overweight or obese participants during a 20-week weight loss treatment. Participants were grouped as either early or late eaters for consuming their main meal, and their energy intake, expenditure, appetite hormones, CLOCK genotype, sleep duration and chronotype were studied. In this study, those who ate their main meal late lost significantly less weight than early eaters. The findings of this study indicate that timing of food intake relates to long-term weight loss effectiveness in humans. These findings may help in developing therapeutic strategies for weight loss that incorporates the timing of food consumption with the traditional energy balance and macronutrient composition.
Abstract
BACKGROUND There is emerging literature demonstrating a relationship between the timing of feeding and weight regulation in animals. However, whether the timing of food intake influences the success of a weight-loss diet in humans is unknown. OBJECTIVE To evaluate the role of food timing in weight-loss effectiveness in a sample of 420 individuals who followed a 20-week weight-loss treatment. METHODS Participants (49.5% female subjects; age (mean ± s.d.): 42 ± 11 years; BMI: 31.4 ± 5.4 kg m(-2)) were grouped in early eaters and late eaters, according to the timing of the main meal (lunch in this Mediterranean population). 51% of the subjects were early eaters and 49% were late eaters (lunch time before and after 1500 hours, respectively), energy intake and expenditure, appetite hormones, CLOCK genotype, sleep duration and chronotype were studied. RESULTS Late lunch eaters lost less weight and displayed a slower weight-loss rate during the 20 weeks of treatment than early eaters (P=0.002). Surprisingly, energy intake, dietary composition, estimated energy expenditure, appetite hormones and sleep duration was similar between both groups. Nevertheless, late eaters were more evening types, had less energetic breakfasts and skipped breakfast more frequently that early eaters (all; P<0.05). CLOCK rs4580704 single nucleotide polymorphism (SNP) associated with the timing of the main meal (P=0.015) with a higher frequency of minor allele (C) carriers among the late eaters (P=0.041). Neither sleep duration, nor CLOCK SNPs or morning/evening chronotype was independently associated with weight loss (all; P>0.05). CONCLUSIONS Eating late may influence the success of weight-loss therapy. Novel therapeutic strategies should incorporate not only the caloric intake and macronutrient distribution - as is classically done - but also the timing of food.
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Impact of five nights of sleep restriction on glucose metabolism, leptin and testosterone in young adult men.
Reynolds, AC, Dorrian, J, Liu, PY, Van Dongen, HP, Wittert, GA, Harmer, LJ, Banks, S
PloS one. 2012;7(7):e41218
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Chronic sleep deprivation is a feature of modern life. It may be due to social, lifestyle and/or occupational demands. It has been associated with metabolic disorders such as type 2 diabetes, metabolic syndrome, insulin resistance and obesity. This study aimed to examine the impact of sleep restriction on glucose metabolism, triglycerides and to explore the impact on testosterone, leptin and cortisol in healthy young men. The sample were 16 men aged between 22 and 36, who did not have any acute or chronic medical or psychological conditions. Subjects were studied in groups of 3 or 4 for 9 consecutive days, and had two baseline nights of 10 hours sleep followed by five nights of 4 hours sleep. Food intake was controlled during the laboratory phase. The study found evidence of impaired glucose metabolism following sleep restriction (elevated glucose and insulin). Researchers suggested this may be due to a rise in afternoon cortisol reflecting adrenal axis activation. Leptin levels also increased, but did not lead to appetite changes. Testosterone levels did not change but SHBG did decrease, possibly due to increases in insulin that could have down-regulated SHBG. There were also alterations in cortisol levels, with elevated levels in the afternoon and evening. The researchers concluded that short term sleep restriction may lead to an increased risk of type 2 diabetes.
Abstract
BACKGROUND Sleep restriction is associated with development of metabolic ill-health, and hormonal mechanisms may underlie these effects. The aim of this study was to determine the impact of short term sleep restriction on male health, particularly glucose metabolism, by examining adrenocorticotropic hormone (ACTH), cortisol, glucose, insulin, triglycerides, leptin, testosterone, and sex hormone binding globulin (SHBG). METHODOLOGY/PRINCIPAL FINDINGS N = 14 healthy men (aged 27.4±3.8, BMI 23.5±2.9) underwent a laboratory-based sleep restriction protocol consisting of 2 baseline nights of 10 h time in bed (TIB) (B1, B2; 22:00-08:00), followed by 5 nights of 4 h TIB (SR1-SR5; 04:00-08:00) and a recovery night of 10 h TIB (R1; 22:00-08:00). Subjects were allowed to move freely inside the laboratory; no strenuous activity was permitted during the study. Food intake was controlled, with subjects consuming an average 2000 kcal/day. Blood was sampled through an indwelling catheter on B1 and SR5, at 09:00 (fasting) and then every 2 hours from 10:00-20:00. On SR5 relative to B1, glucose (F(1,168) = 25.3, p<0.001) and insulin (F(1,168) = 12.2, p<0.001) were increased, triglycerides (F(1,168) = 7.5, p = 0.007) fell and there was no significant change in fasting homeostatic model assessment (HOMA) determined insulin resistance (F(1,168) = 1.3, p = 0.18). Also, cortisol (F(1,168) = 10.2, p = 0.002) and leptin (F(1,168) = 10.7, p = 0.001) increased, sex hormone binding globulin (F(1,167) = 12.1, p<0.001) fell and there were no significant changes in ACTH (F(1,168) = 0.3, p = 0.59) or total testosterone (F(1,168) = 2.8, p = 0.089). CONCLUSIONS/SIGNIFICANCE Sleep restriction impaired glucose, but improved lipid metabolism. This was associated with an increase in afternoon cortisol, without significant changes in ACTH, suggesting enhanced adrenal reactivity. Increased cortisol and reduced sex hormone binding globulin (SHBG) are both consistent with development of insulin resistance, although hepatic insulin resistance calculated from fasting HOMA did not change significantly. Short term sleep curtailment leads to changes in glucose metabolism and adrenal reactivity, which when experienced repeatedly may increase the risk for type 2 diabetes.
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Sleep restriction for 1 week reduces insulin sensitivity in healthy men.
Buxton, OM, Pavlova, M, Reid, EW, Wang, W, Simonson, DC, Adler, GK
Diabetes. 2010;59(9):2126-33
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Short sleep duration is associated with an increased risk of many chronic diseases including diabetes, however the effects of sleep restriction on insulin sensitivity have not yet been established. The aim of study was to assess the effects of decreased sleep duration on insulin sensitivity in a controlled environment. This 12-day inpatient study included 20 healthy men who were randmoised to receive a wakefulness-promoting drug, modafinil, or placebo during the sleep restriction phase. This study showed that sleep restriction for one week significantly reduces insulin sensitivity. These findings raise concerns about chronic insufficient sleep on the development of metabolic diseases and promote further research into these effects.
Abstract
OBJECTIVE Short sleep duration is associated with impaired glucose tolerance and an increased risk of diabetes. The effects of sleep restriction on insulin sensitivity have not been established. This study tests the hypothesis that decreasing nighttime sleep duration reduces insulin sensitivity and assesses the effects of a drug, modafinil, that increases alertness during wakefulness. RESEARCH DESIGN AND METHODS This 12-day inpatient General Clinical Research Center study included 20 healthy men (age 20-35 years and BMI 20-30 kg/m(2)). Subjects spent 10 h/night in bed for >or=8 nights including three inpatient nights (sleep-replete condition), followed by 5 h/night in bed for 7 nights (sleep-restricted condition). Subjects received 300 mg/day modafinil or placebo during sleep restriction. Diet and activity were controlled. On the last 2 days of each condition, we assessed glucose metabolism by intravenous glucose tolerance test (IVGTT) and euglycemic-hyperinsulinemic clamp. Salivary cortisol, 24-h urinary catecholamines, and neurobehavioral performance were measured. RESULTS IVGTT-derived insulin sensitivity was reduced by (means +/- SD) 20 +/- 24% after sleep restriction (P = 0.001), without significant alterations in the insulin secretory response. Similarly, insulin sensitivity assessed by clamp was reduced by 11 +/- 5.5% (P < 0.04) after sleep restriction. Glucose tolerance and the disposition index were reduced by sleep restriction. These outcomes were not affected by modafinil treatment. Changes in insulin sensitivity did not correlate with changes in salivary cortisol (increase of 51 +/- 8% with sleep restriction, P < 0.02), urinary catecholamines, or slow wave sleep. CONCLUSIONS Sleep restriction (5 h/night) for 1 week significantly reduces insulin sensitivity, raising concerns about effects of chronic insufficient sleep on disease processes associated with insulin resistance.