All About Sleep |

We are often told that we need to get plenty of sleep and that this is the most important thing. It is clearly true that if you do not get enough sleep, you will not function effectively. However, the “number of hours of sleep you need” is a common myth. You need to get the right amount of sleep for your body to function.

Sleep is one of the most important things you do as a human being. It’s also something that we’re not as good at as we think we are, with many of us not getting the quality sleep we need. We tend to think of sleep as a constant state of being, but in reality, it’s something that changes with age and lifestyle.

When humans sleep, our bodies go into a temporary state of rest and our metabolism slows down, allowing the body to produce less heat. This is why it is important to keep a regular sleep schedule and avoid bad habits such as too much caffeine, junk food and alcohol.

People will go to great lengths to ensure that their workout routine, dietary plan, and supplementation regimen are all sensible and well-structured. However, they often overlook or disregard the importance of sleep and sleep quality.

Sleep is necessary for life and good health. Even if you don’t eat properly, you may expect to live for 75 years or more. If you don’t get enough sleep, you’ll probably pass out in a few weeks – the Guinness World Record for sleep deprivation is 11 days. (See Scientific American: How Long Can Humans Stay Awake?) for additional information.

Even though medical students and parents of infants may feel as if they are unintentionally attempting to beat that record, the majority of you aren’t likely to try any time soon. But, even if you fulfill the bare minimum of sleep requirements, are you sleeping optimally? What impact can poor sleep quality have on your body composition and eating habits if you don’t get enough sleep? Are individuals tired, overfed, and unable to make healthy food choices each day as a result of late evenings in front of the TV, internet, or refrigerator?


What you should be aware of when it comes to sleep

The typical adult sleeps for approximately 7 hours each night. 33 percent of the population sleeps for less than 6.5 hours each night (no surprise the globe seems a little grumpy and preoccupied at times!). Women get a little more sleep than males. Those with a high body fat percentage sleep less than those with a normal body fat percentage. According to studies, individuals who sleep less than 6 hours per night acquire almost twice as much weight as those who sleep 7 to 8 hours each night during a 6-year period. Excessive sleep isn’t always better: those who sleep more than 9 hours a night have the same body composition as others who sleep less than 6 hours.


Why are you sleeping less?

Although many of us may believe that work requires a lot of our concentration or that we can’t get our minds to shut off, the true cause of sleep deprivation is usually deliberate bedtime delay rather than lengthy work hours or physiologic abnormalities. We don’t get enough sleep because we don’t want to. We sit in front of the television. We use the internet to get information. We had a night out with our pals. This deliberate bedtime postponement is unique to contemporary culture. A century ago, the typical American slept almost 9 hours each night. Based on the normal sleep/wake cycle of the brain, people would likely sleep for approximately 8 hours each night if artificial stimulation and excessive work/life demands were removed.

“Sleep deprivation as a result of deliberate bedtime reduction has become a characteristic of contemporary life… Chronic sleep loss, whether caused by behavioral or sleep disorders, may be a new risk factor for obesity, insulin resistance, and Type 2 diabetes.” — K. Spiegel

According to US experts, regular exercise may lower a woman’s cancer risk, but the advantages may fade if she gets too little sleep.

Body composition and sleep

According to a 2005 research with a nationally representative sample of approximately 10,000 people, the obesity pandemic in the United States may be exacerbated by a similar reduction in the average number of sleep hours. People between the ages of 32 and 49 who sleep less than 7 hours each night are considerably more likely to be fat, according to one research. Additionally, being up beyond midnight seemed to raise the risk of obesity. These links have a “dose-response” connection, with later bedtimes and shorter sleeping hours leading to more body fat accumulation. Obesity was not shown to be associated with wake-up time. Similarly, a research that tracked the development of almost 9,000 children from infancy to age seven found that children who slept the least at 30 months were more likely to be fat at age seven than children who slept more.

It’s still unclear if lack of sleep is a cause or a consequence of increased body fat (or both). Sleep deprivation, according to some experts, may alter appetite-regulating hormones, resulting in body fat gain. Others think that the physical pain of obesity and sleep apnea makes it difficult to obtain a decent night’s sleep.

While there are numerous reasons why lack of sleep may affect body fat, one of them could be the increased cortisol, reduced growth hormone (GH), and thyroid stimulating hormone (TSH) that occurs in the evening. Furthermore, prolonged sleep deprivation causes an increase in sympathetic nerve activity as well as a delayed insulin response. This is the ideal storm of side effects for exacerbating obesity:

  • A decrease in glucose tolerance (GT)
  • Sympathovagal balance is improved.
  • Cortisol levels in the evening and at night are higher.
  • Leptin levels have dropped.
  • Thyroid stimulating hormone deficiency (TSH)

In practical terms, loss of sleep may contribute to increased body fat since more time spent awake equals more time to consume. At 1 a.m., those junk food ads start to seem very tempting.

What about the hormones that control hunger? A study of 12 young, healthy, normal-weight males showed that sleeping for four hours two nights in a row (without napping) resulted in decreased leptin levels and greater ghrelin levels. Due to the fact that low leptin and high ghrelin both increase hunger and appetite, the males reported greater overall hunger levels, particularly for energy-dense, processed items like sweets, baked goods, and bread. There will be no cravings for greens or kidney beans. As a consequence, experts believe that dysregulation of hunger hormones may be another explanation for body fat accumulation caused by sleep deprivation.

Actions of and relationships between leptin and ghrelin

The actions of leptin and ghrelin, as well as their connections

So, decreased sleep may lead to an increase in body fat, which is a major issue. That isn’t the case. If you receive fewer than 7.5 hours of sleep each night, you’re more likely to have a heart attack, stroke, or sudden cardiac death than your friends who get lots of shut-eye. Insulin resistance (IR), glucose intolerance, and type 2 diabetes are all prone to develop as a result of the lack of sleep.

Take a look at this: For six nights, eleven healthy males in their twenties were only given 4 hours of sleep. The young guys had the insulin sensitivity of a 70-year-old pre-diabetic at the end of it! Despite the study’s limited sample size, the findings are promising.

Daily living functions, such as emotions, cognition, and memory, may be harmed by a lack of sleep. Going 24 hours without sleep is comparable to functioning with a 0.10 percent blood alcohol level. You’ll have a hard time navigating the grocery store and/or the gym when “intoxicated” from a lack of sleep.

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What is the significance of sleep?

Cycles of hormones

The suprachiasmatic nucleus (SCN) is a brain “clock” that controls our circadian cycle. Exposure to light and dark may affect our daily cycles since the SCN is located right above where the optic nerve crosses the hypothalamus. Many hormones, including growth hormone, thyroid stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), prolactin, melatonin, and testosterone, have regular diurnal cycles. A consistent sleep schedule (going to bed and waking up at the same time every day) may help to trigger the SCN and promote a deep, regular sleep pattern.

The conscious mind and the outer world are separated by a perceptual wall created by sleep. Closing our eyelids makes sleeping easier, yet we might sleep just as well without them. Melatonin is released into the circulation by the pineal gland in the hours leading up to sleep, mostly in reaction to variations in the light/dark cycle.

Stages of sleep

During sleep, there are five phases. Phases one and two are light sleep, whereas stages three and four are profound sleep. GH secretion takes place in phases three and four. Stage five is when you have rapid-eye movement (REM) sleep, which is when you dream. Every 90 minutes, a complete cycle through these five phases happens. If several complete cycles of sleep aren’t achieved most nights, GH secretion may decrease, affecting physical and mental recovery.


Not only is GH secretion reduced when a person sleeps less than their body requires, but overall exercise performance may suffer as well. It may seem that the exerciser is working very hard when they aren’t.

“People just do not understand the importance of sleep or the health implications of not obtaining a decent night’s sleep on a regular basis… Sleep is equally as essential as food and exercise for overall health.” –Carl Hunt, MD, head of the National Institutes of Health’s National Center for Sleep Disorders Research

Other intriguing sleep-related facts

Sleep debt builds up over time, so the more nights you go without getting enough sleep, the more likely you are to experience unfavorable consequences. The good news is that you can make up for lost time by sleeping well for a few nights in a row. Experts believe that each hour of sleep debt must be repaid at some point.

Soft tissue collapse causes obstructive sleep apnea (OSA), which is an obstruction in the airway. It’s extremely prevalent, perhaps because high body fat is a significant risk factor. OSA may make it difficult to get a good night’s sleep since the airway is constricted – and patients may even cease breathing for short periods of time. Following OSA surgery, there has been no discernible improvement.

Cortisol, a stress hormone, in high quantities may have a detrimental impact on sleep quality. PS is an excellent cortisol regulator and suppressor, and it may help regulate evening cortisol levels, resulting in improved sleep quality. Valerian root may also be beneficial. The majority of PN customers who complained of sleep difficulties while on a high-volume exercise and/or calorie-restricted diet reported that supplementing with phosphaditylserine improved sleep quality. One dosage in the early evening (5-6 p.m.) and one dose approximately an hour before bedtime are recommended. (If you’re on medication, pregnant, or nursing, see your doctor; a list of valerian drug interactions may be found here.) PS is only beneficial to insomniacs who have high evening cortisol levels. Cortisol may also be controlled by eating enough carbs and protein after exercise.

Many tricyclic antidepressants (e.g., Desipramine [Norpramin], Doxepin [Sinequan], Imipramine [Tofranil]) have been shown to reduce REM sleep, adding to the notion that mood and sleep are linked.

Sleep may aid in the development and recall of memories.

Knowing you’ll be able to sleep throughout the day may help you maintain a healthy blood pressure level.

Conclusions and suggestions

The majority of study results back up the theory that sleep length is linked to obesity. As a result, choosing an appropriate sleeping strategy should be a part of your healthy living and eating routine. We live in a fast-paced world, but we are not victims. While we have more options than ever before, such as 24 hour cable/satellite TV, internet, email, longer job hours, family obligations, 24 hour shopping, and so on, we still have a lot of control over what we do. Sleep deprivation is typically a reflection of our priorities rather than actual limitations.

If you’re worried about your sleep quality or quantity, start by determining if you’re getting enough sleep. Sleep specialists often suggest a sleep journal, much as we do with diet diaries. Do you get 7-9 hours of sleep each night? If not, what is the reason? Is it a result of poor sleeping habits, medicines, or another bad habit? Get to the bottom of the issue and start enjoying the advantages of getting enough sleep.

Second, prioritize excellent sleep, just as you would the rest of your healthy routines. When creating a sleeping schedule, consider the following factors:

  • Maintain a reasonably regular bedtime and wake-up time. On weekends, staying up late and sleeping in may throw off your weekly schedule.
  • Keep the bedroom as dark as possible to signal to the body’s light-sensitive clock that it’s time to sleep.
  • Keep the bedroom as quiet as possible or use a white noise machine (such as a fan).
  • Relaxation/routine: Establish a soothing and familiar pre-bed ritual. Work, internet usage, movies, and late-night deep/stressful conversations may all disturb sleep.
  • Maintain a cool indoor temperature of 66-72 degrees Fahrenheit (18-22 degrees Celsius).
  • Caffeine and nicotine are stimulants that should be avoided, particularly later in the day.
  • Exercise: Not only is it excellent for a tight butt and huge guns, but it may also help you sleep better.
  • Fullness: Eating a heavy supper may make it difficult to sleep.


To see the information sources mentioned in this article, go here.

Sleep increases nocturnal plasma ghrelin levels in healthy individuals, according to Dzaja et al. 2004;286:E963-E967 in Am J Physiol Endocrinol Metab.

Relationship between sleep quality and glucose control in normal people, Sheen AJ, et al. Am J Physiol, vol. 271, no. E261-E270, 1996.

Sekine M, et al. A dose-response relationship between short sleeping hours and childhood obesity: results of the Toyama Birth Cohort Study. Child: Care, Health & Development 2002;28:163-170.

K. Spiegel, R. Leproult, and E.V. Cauter. Sleep deprivation has an impact on metabolic and endocrine function. The Lancet, 354, 1435-1439, 1999.

Dawson D & Reid K. Fatigue, alcohol and performance impairment. Nature 1997;388:235.

The National Sleep Foundation is a non-profit organization dedicated to improving sleep The National Sleep Foundation conducted an omnibus “Sleep in America” poll in 2000. On November 13, 2008, I was able to get this information.

Webb WB & Agnew HW. Are we chronically sleep deprived? Bull Psychon Soc 1975;6:47-48.

Diabetes Care 2001;24:608. Shigeta H, et al. Lifestyle, obesity, and insulin resistance.

Overweight and obese patients in a primary care population report less sleep than patients with a normal body mass index, according to Voronoa RD, et al. 165:25-30 in Arch Intern Med, 2005.

JT Arnedt, et al. How do the effects of extended wakefulness and alcohol differ on a simulated driving task? 337-344 in Accid Anal Prev, 2001.

Avon Longitudinal Study of Parents and Children Study Team. BMJ 2005;330:1357. Reilly JJ, et al.

K. Spiegel et al. Short communication: Sleep deprivation is linked to lower leptin levels, higher ghrelin levels, and increased hunger and appetite in healthy young males. 846-850 in Ann Intern Med, 2004.

Inadequate sleep as a risk factor for obesity: Analyses of the NHANES I. SLEEP 2005;28:1289-1296. Gangwisch JE, et al.

Effect of shift work on body mass index: results of a study conducted in 319 glucose-tolerant men working in a Southern Italian industry, Di Lorenzo L, et al. International Journal of Obesity, Relativity, and Metabolic Disorders, vol. 27, no. 3, pp. 1353-1358, 2003.

R. Rosmond, L. Lapidus, and P. Bjorntorp. Obesity and body fat distribution in middle-aged men: the impact of occupational and social variables. 1996;20:599-607. Int J Obes Relat Metab Disord

Sleep loss: a new risk factor for insulin resistance and Type 2 diabetes, Spiegel K, et al. 2005;99:2008-2019 in J Appl Physiol.

Health habits of U.S. adults, 1985: the “Alameda 7” revisited, Schoenborn CA. Public Health Reports, vol. 101, no. 5, pp. 571-580, 1986.

T&C Mag – Oct 2008. The ZZZ Factor. Art Horne. [email protected]

Acute alterations in cardiovascular function during the beginning phase of daytime sleep: a comparison to laying awake and standing, Zaregarizi M, et al. J Appl Physiol 103:1332-1338, 2007.

AG Elshaug et al. Upper airway surgery should not be used as a first-line therapy for individuals with obstructive sleep apnea. BMJ 336:44-45, 2008.

Short sleep duration as an independent predictor of cardiovascular events in Japanese hypertensive patients, Eguchi K, et al. Arch Intern Med, 2008, vol. 168, no. 22, pp. 2225-2231.

Dement WC & Vaughan C. The Promise Of Sleep. 1999. Delacorte Press.

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Whether you’re a parent, a student, or just someone who needs a good night’s sleep, you know the importance of a good night’s rest. And that’s exactly what this blog is all about! I’ll be writing about everything sleep-related, from the benefits of sleep to common sleep disorders, and everything in between.. Read more about sleep facts for students and let us know what you think.

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Una is a food website blogger motivated by her love of cooking and her passion for exploring the connection between food and culture. With an enthusiasm for creating recipes that are simple, seasonal, and international, she has been able to connect with people around the world through her website. Una's recipes are inspired by her travels across Mexico, Portugal, India, Thailand, Australia and China. In each of these countries she has experienced local dishes while learning about the culture as well as gaining insight into how food can be used as a bridge between different cultures. Her recipes are often creative combinations of traditional ingredients from various different cuisines blended together to create something new.