Waking window

Your body loves routine. Mastering sleep schedules help to balance circadian rhythm, thus, falling asleep and waking up becomes easier.

Complete this habit when you wake up and go to sleep under schedule.

Sleep is essential for the body and the brain to recover from the previous day, heal when sick, and function at its total capacity. Proper sleep slows the effects of aging and highly determines the quality of our lives, thus, having both - a correct length and quality of sleep - should be the foundation when pursuing a healthy lifestyle. 

Studies have indicated that the best:

• sleep time is between 9:57 PM and 1:06 AM;
• wake-up time is between 6:55 AM and 8:52 AM;
• sleep duration is 6-8 hours per night;

Recommendations to ensure falling asleep smoothly:

• increase physical activity throughout the day;
• eat more plant-based foods;
• reduce caffeine intake in the second half of the day (caffeine's effects on the body last for 12 hours and might affect the quality of your sleep);
• do not consume alcohol;
• stick close to the same sleep schedule on weekends or days off;
• see other habits - Daylight Viewing and Wind Down.

Improve your sleep quality by setting up the right environment:

• the optimal room temperature for good sleep is 64-66 Fahrenheit (18-19 Celcius);
• the bedroom should be as dark as possible. One study revealed that a dimly lit environment negatively affects the autonomic nervous system by increasing insulin resistance and heart rate and decreasing heart rate variability.

Impact

Sleep has remarkable restorative powers. It can counteract insulin resistance, poor mood and cognition, high blood pressure, and even healing pathways.

During sleep, the toxins that build up during the day are cleaned up by the glymphatic system. It loses effectiveness as we age, especially when we don't sleep properly. Harmful waste in our system starts to build up faster than it can be cleared away. Even a single night of missed sleep leads to an accumulation of toxins in the brain that predispose people to neurodegenerative diseases.

Sleep is vital for balancing hormones. For instance, going to sleep 1-2 hours later disrupts the regular release of growth hormone, which is essential for cell reproduction and regeneration. 

Imbalanced sleep duration has dramatic effects on our health. For instance, too much or insufficient sleep can lead to a higher risk of death due to cardiovascular disease, cancer, and other causes. A scientific study proved a 30% increase in the relative risk of death in people who slept too much, while those who slept too little had a 12% higher relative risk of death. Research in laboratory animals concluded that insufficient sleep produces reactive oxygen species in the gut, thus shortening lifespan.

A study with 363,886 adults proved that higher sleep quality is associated with a lower biological age. Meanwhile, in another study that tracked 328,850 people, people with better sleep quality were 15% less likely to develop diabetes, stroke, dementia, chronic obstructive pulmonary disease, congestive heart failure, myocardial infarction, or cancer.

Telomeres

Two independent studies published in 2018 and 2022 confirmed the impact of quality and duration of sleep on the central longevity biological factors – telomeres. Poor sleep quality, concise sleep duration, long sleep latency, and low sleep efficiency were associated with faster longitudinal shortening of telomeres.

 According to these studies, people who slept less than 6 hours per night, had an insomnia disorder, or slept longer than 8 hours were associated with short telomeres. The longest telomeres were found in people who slept 6-8 hours per night. Sleep latency was another indicator of telomere length. Telomeres were shortening faster when sleep latency was 25 min. The slowest shortening of telomeres was in a group of people who needed just 10 min for sleep latency.

Mason, I. C., Grimaldi, D., Reid, K. J., Warlick, C. D., Malkani, R. G., Abbott, S. M., & Zee, P. C. (2022). Light exposure during sleep impairs cardiometabolic function. Proceedings of the National Academy of Sciences of the United States of America, 119(12), e2113290119. https://doi.org/10.1073/pnas.2113290119

Cappuccio et al. Sleep duration and all-cause mortality: a systematic review and meta-analysis of prospective studies. Sleep 2010. https://doi.org/10.1093/sleep/33.5.585

Vaccaro et al. Sleep Loss Can Cause Death through Accumulation of Reactive Oxygen Species in the Gut. Cell 2020. https://doi.org/10.1016/j.cell.2020.04.049

Carroll et al. Postpartum sleep loss and accelerated epigenetic aging. Sleep Health 2021. https://doi.org/10.1016/j.sleh.2021.02.002

Svensson et al. Association of Sleep Duration With All- and Major-Cause Mortality Among Adults in Japan, China, Singapore, and Korea. JAMA Network Open 2021. https://doi.org/10.1001/jamanetworkopen.2021.22837

Sambou et al. Associations Between Sleep Quality and Health Span: A Prospective Cohort Study Based on 328,850 UK Biobank Participants. Frontiers in Genetics 2021. https://doi.org/10.3389/fgene.2021.663449

Gao et al. Role of sleep quality in the acceleration of biological aging and its potential for preventive interaction on air pollution insults: Findings from the UK Biobank cohort. Aging Cell 2022. https://doi.org/10.1111/acel.13610

Tempaku P, Hirotsu C, Mazzotti D, Xavier G, Maurya P, Brietzke E, Belangero S, Poyares D, Bittencourt L, Tufik S. Long Sleep Duration, Insomnia, and Insomnia With Short Objective Sleep Duration Are Independently Associated With Short Telomere Length. J Clin Sleep Med. 2018 Dec 15;14(12):2037-2045. doi: 10.5664/jcsm.7532. PMID: 30518442; PMCID: PMC6287731.

Jin JH, Kwon HS, Choi SH, Koh SH, Lee EH, Jeong JH, Jang JW, Park KW, Kim EJ, Kim HJ, Hong JY, Yoon SJ, Yoon B, Park HH, Ha J, Park JE, Han MH. Association between sleep parameters and longitudinal shortening of telomere length. Aging (Albany NY). 2022 Apr 2;14(7):2930-2944. doi: 10.18632/aging.203993. Epub 2022 Apr 2. PMID: 35366243; PMCID: PMC9037260.

Wynchank D, Bijlenga D, Penninx BW, Lamers F, Beekman AT, Kooij JJS, Verhoeven JE. Delayed sleep-onset and biological age: late sleep-onset is associated with shorter telomere length. Sleep. 2019 Oct 9;42(10):zsz139. doi: 10.1093/sleep/zsz139. PMID: 31270544.

Mazzotti DR, Guindalini C, Moraes WA, Andersen ML, Cendoroglo MS, Ramos LR, Tufik S. Human longevity is associated with regular sleep patterns, maintenance of slow wave sleep, and favorable lipid profile. Front Aging Neurosci. 2014 Jun 24;6:134. doi: 10.3389/fnagi.2014.00134. PMID: 25009494; PMCID: PMC4067693.