Besedovsky, L., Lange, T., & Born, J. (2012). Sleep and immune function. Pflügers Archiv: European Journal of Physiology, 463(1), 121–137. Consensus Conference Panel, Watson, N. F., Badr, M. S., Belenky, G., Bliwise, D. L., Buxton, O. M., Buysse, D., Dinges, D. F., Gangwisch, J., Grandner, M. A., Kushida, C., Malhotra, R. K., Martin, J. L., Patel, S. R., Quan, S. F., Tasali, E., Non-Participating Observers, Twery, M., Croft, J. B., Maher, E., … Heald, J. L. (2015). Recommended amount of sleep for a healthy adult: A joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. Journal of Clinical Sleep Medicine, 11(6), 591–592. Ju, Y. S., Ooms, S. J., Sutphen, C., Macauley, S. L., Zangrilli, M. A., Jerome, G., Fagan, A. M., Mignot, E., Zempel, J. M., Claassen, J., & Holtzman, D. M. (2017). Slow wave sleep disruption increases cerebrospinal fluid amyloid-β levels. Brain: A Journal of Neurology, 140(8), 2104–2111. only the ones that are most relevant to avoid saturating memory pathways. Although this theory is still under investigation, evidence shows that people obtain a higher proportion of deep sleep after learning a new task, and show higher concentrations of slow waves in brain areas related to the task. To calculate how much deep sleep you need, first determine how much sleep you need overall. Most adults should aim for at least seven hours

Additionally, sleep deprivation is associated with hormonal changes that drive our appetite for high-calorie food. Going short on slow-wave sleep, in particular, is believed to contribute to insulin resistance and the development of type 2 diabetes and heart disease. Catching up on sleep may reverse some of these effects While all stages of sleep are necessary for good health, deep sleep offers specific physical and mental benefits. During deep sleep, your body releases growth hormone and works to build and repair muscles, bones, and tissue. Deep sleep also promotes immune system functioning. Additionally, slow-wave sleep may be important for regulating glucose metabolism To a certain extent, the body self-regulates deep sleep. For example, you might spend more time in deep sleep if you are recovering from a period of sleep deprivation. By contrast, people who nap frequently may experience less deep sleep, as part of their deep sleep needs have already been fulfilled during the day. Typically, you descend into deep sleep within an hour of falling asleep, and experience progressively shorter periods of deep sleep as the night wears on. During deep sleep, body functions like breathing and heart rate are also very slow and your muscles are relaxed. It can be difficult for someone to wake you up, and waking up out of deep sleep may make you feel mentally foggy for up to an hour. What Are the Stages of Sleep? Take a warm bath: Heating your body at least an hour before bedtime may help induce slow-wave sleep. The warmth from the bath draws heat to your hands and feet which then dissipates. The process allows you to cool down to a comfortable temperature for sleeping.Stage 2: In this stage of light sleep, your breathing and heart rate slow even more. Your temperature drops, and your muscles relax. Stage 2 sleep lasts longer in each cycle throughout the night. About half of your total sleep

Some people with insomnia experience changes in their sleep cycles and, as a result, may have more stage 1 sleep and less deep sleep. Stress and aging can also reduce levels of deep sleep. Additionally, people with conditions such as schizophrenia and Alzheimer’s disease experience less slow wave sleep. Ensuring you get sufficient sleep overall can help you get the deep sleep you need. By establishing consistent sleep and wake times, you can develop a healthy sleep schedule for your body. Practicing good sleep hygiene can also help you get more sleep in total. Healthy sleep habits include:A member of our medical expert team provides a final review of the content and sources cited for every guide, article, and product review concerning medical- and health-related topics. Inaccurate or unverifiable information will be removed prior to publication.