Sleep

1. Prioritize 7–9 Hours of Quality Sleep per Night
Insufficient sleep is linked with an increased risk of cardiovascular disease, diabetes, and obesity (https://doi.org/10.3390/healthcare7010001). In addition, it is associated with increased inflammation, oxidative stress, and low antioxidant levels (https://doi.org/10.1155/2015/824589). High-quality sleep has also emerged as a strong protective factor against cognitive decline and the development of dementia (https://doi.org/10.1097/YCO.0000000000000106). A single night of sleep deprivation will spike cortisol levels the next day (https://doi.org/10.1093/sleep/20.10.865) and will reduce the activity of natural killer cells (immune cells that detect and eliminate cancerous cells) (https://doi.org/10.1097/00006842-199411000-00004). Interestingly, getting too much sleep has also been linked to increased risk of cardiometabolic disease, mortality, and accidental injury, suggesting there may be a "sweet spot" for sleep duration (https://doi.org/10.1093/SLEEP/27.3.440, https://doi.org/10.2337/DIACARE.29.03.06.DC05-0879, https://doi.org/10.1016/j.sleh.2017.03.006, https://doi.org/10.1177/0194599815604103).

2. Maintain Regular Sleep-Wake Time
While total sleep time is important, maintaining consistent sleep-wake patterns (even on weekends 🙂) may be even more critical for well-being. Regularizing sleep schedules has been shown to reduce daytime sleepiness more effectively than simply increasing sleep duration (https://doi.org/10.1093/SLEEP/19.5.432). Adults with earlier and more consistent sleep timing tend to experience better health outcomes (https://doi.org/10.1139/apnm-2020-0032), and cognitive performance is optimized when sleep-wake cycles remain aligned with the body’s internal circadian rhythms (https://doi.org/10.1162/jocn.2006.18.4.508). Disruptions to these rhythms are linked with delayed circadian timing and even diminished academic performance amongst students (https://doi.org/10.1093/SLEEP/34.2.235). Light seems to play a crucial role in synchronizing the circadian system to the external environment, reinforcing the importance of maintaining exposure to natural light during the day (https://doi.org/10.1177/0748730405277983). Irregular sleep routines have also been associated with lower physiological arousal, impaired psychomotor performance, and more negative mood states (https://doi.org/10.1016/0301-0511(78)90041-8).

3. Protect Your Sleep Environment
People with insomnia often show less regularity in their daily routines compared to good sleepers, suggesting that maintaining consistent habits may support better nighttime rest (https://doi.org/10.3109/07420528.2014.956361). Exposure to screens in the evening (i.e. phones, tablets, and televisions) is consistently linked to poorer subjective sleep quality (https://doi.org/10.1093/eurpub/ckae144.164, https://doi.org/10.1016/j.sleh.2019.11.007). This effect may be driven in part by the suppressive impact of artificial light on melatonin (the hormone that "kicks off" sleep) production, which delays sleep onset and disrupts circadian rhythms. In fact, nighttime exposure to ambient light has been associated with increased rates of sleep disturbances and shorter sleep duration (https://doi.org/10.1016/j.scitotenv.2022.159303). Incorporating relaxing activities before bed has been shown to reduce the time it takes to fall asleep, especially when compared to stimulating tasks like exercise or cognitive vigilance (https://doi.org/10.1111/J.1469-8986.1976.TB00876.X).

4. Avoid Substances that Disrupt Sleep Architecture
When consumed near bedtime, caffeine has consistently been shown to delay sleep onset, reduce total sleep time and sleep efficiency, and worsen perceived sleep quality (https://doi.org/10.1016/j.smrv.2016.01.006, https://doi.org/10.1016/j.smrv.2023.101764). Nicotine, whether through cigarette smoking or other forms, also interferes with sleep. It is associated with shorter sleep duration, greater daytime sleepiness, and disrupted sleep patterns (https://doi.org/10.1097/ADT.0000000000000123, https://doi.org/10.2147/NSS.S18891). Alcohol, leads to abnormal sleep architecture by suppressing REM sleep and increasing slow-wave sleep, ultimately impairing sleep continuity (https://doi.org/10.1111/acer.12006). Chronic alcohol consumption is also linked to a higher risk of sleep-disordered breathing in men (https://doi.org/10.5664/JCSM.26795). Avoiding these substances (particularly in the evening) can help protect the integrity of natural sleep cycles and promotes more restorative rest.