Sleep You Need:

How Much Sleep Do You Really Need to Be Healthy?

By Dr. Ben Kim

Few facets of your life have greater impact on your health status than the amount of quality rest that you get each night.

Why is your sleeping routine so important to your ability to prevent disease and be at your best?

Because it is during restful sleep that your body releases large amounts of three hormones that are essential to your ability to heal and rejuvenate your cells. These three hormones, the real fountains of youth for your body, are as follows:

  1. Erythropoietin

    Erythropoietin is a hormone that is produced by your kidneys. It stimulates the production of red blood cells by your bone marrow. Red blood cells deliver oxygen to every cell in your body. Red blood cells also carry carbon dioxide (waste) away from every cell in your body.

    How big a difference can the amount of erythropoietin in your circulation mean to your overall sense of vitality? The fact that erythropoietin is a common blood doping agent in sports such as marathon running and long-distance cycling speaks volumes about its ability to improve your stamina.

    If you get enough sleep each day, there is no need to inject erythropoietin into your system - your body will produce all the erythropoietin that you need.

  2. Growth Hormone

    Growth hormone is released by your pituitary gland in episodic waves, about once every ninety minutes, with the strongest wave coming approximately one hour after you fall asleep at night.

    Growth hormone stimulates growth and reproduction of your cells. When released by your pituitary gland in amounts that are in line with your physiological needs, growth hormone can help keep your muscles and bones strong. Growth hormone can also decrease the amount of adipose (fat) tissue that you carry.

    A lack of adequate growth hormone production is one of the chief reasons why people who do not get enough sleep tend to be overweight for their height and/or have weak muscles and bones.

  3. Testosterone

    Testosterone is a steroid hormone that is secreted by the testicles of males and the ovaries of females. Small amounts of testosterone are produced and secreted by the outer section of your adrenal glands and by the placenta in pregnant women.

    Adequate testosterone secretion is essential to experiencing:

    • A strong immune system
    • High energy
    • Strong bones and reduced risk of developing osteoporosis
    • A healthy sex drive

If you do not get enough sleep on a daily basis, your body will still produce erythropoietin, growth hormone, and testosterone - it just won't produce amounts that will allow you to experience your best health.

The amount of sleep you need each day to be at your best fluctuates in response to several factors, the two most important ones being:

  1. Your Physical and Emotional Activity Levels

    The more energy you expend physically and/or emotionally, the more sleep you need.

    You might think that people who spend 8 hours a day doing heavy manual labor would need more sleep than folks who engage in very little physical activity. In actuality, if physically inactive people spend most of their waking hours expending emotional energy associated with states like depression, anxiety, and anger, then they may need just as many hours of quality sleep as those who do heavy physical labor each day.

    The primary purpose of sleep is to allow your body to produce large quantities of the hormones mentioned above, and devote the bulk of your resources to healing and rejuvenating your cells for another day. The more energy you spend physically and/or emotionally, the more time you need in slumber for adequate rejuvenation.

  2. Your Diet

    Whenever you overeat or eat large amounts of processed foods, your digestive organs stand a good chance of working overtime while you sleep in order to fully deal with extra digestive burden.

    This expenditure of digestive energy while you sleep cuts into the resources that are available for the healing and rejuvenation that sleep is intended for, which can increase the number of hours of sleep that you need to feel well rested.

    Whenever you eat fresh, uncooked vegetables and fruits, your body receives enzymes that naturally occur in raw vegetables and fruits. These enzymes can actually improve the efficiency of your digestive system. For this reason, people who eat lots of fresh, uncooked produce typically find that they need less sleep than people who eat mainly cooked and heavily processed foods.

Ultimately, the amount of sleep you need to be optimally well is best determined by allowing your body to sleep until you naturally wake up feeling well rested.

Whenever you wake up feeling well rested, you can be relatively certain that you have given your body a chance to produce adequate quantities of erythropoietin, growth hormone, and testosterone, and that your body has had ample time to rejuvenate your cells.

Ideally, you want to establish a pattern of going to sleep at an hour that will lead to you waking up naturally around the time that you have to begin your day. For example, if over time, you discover that your body tends to need approximately 9 hours of sleep per night for you to feel well rested, and you need to begin your day at 6 am, then you should do your best to get to sleep at around 9 pm each evening.

Keep in mind that if your body has been deprived of adequate sleep for more than a few days, you may have significant sleep debt. In this case, you will need to pay off your sleep debt by giving your body as much rest as your life circumstances will allow before you can use your feelings of restfulness or fatigue in the mornings as accurate barometers of adequate sleep time.

Remember: the number of hours that you need to experience your best health is unique, and may fluctuate slightly from week to week in accordance with how much physical and emotional energy you put out, and also in accordance with the quality of your food choices.

What follows are some important tips on how to ensure that your sleeping hours translate to acquiring high quality rest:

  1. In the spring, summer, and fall months, use window coverings that prevent the early morning sunlight from waking you up before your body is fully rested. Alternatively, use an eye mask to block out light while you are sleeping.
  2. If you share your bed with other living creatures like your partner, your children, and/or pets, be sure that you communicate what you need in order to sleep peacefully. Some people sleep better when they cuddle (my wife), while others can't sleep a wink if so much as another person's fingernail is touching their shoulder (me). Know your optimal sleeping conditions and let them be known to relevant crew members.
  3. Try not to drink fluids or eat water-rich foods within an hour or two of going to bed. The less you have to get up during the night to go to the bathroom, the higher quality rest you will enjoy.
  4. Strive to avoid powerful stimulants like sugar and caffeine, especially in the late afternoon and evening. When you make it a habit to get adequate sleep each night, you will have less of a need for such stimulants to keep you going throughout the day.
  5. Strive to do something that relaxes your body and mind an hour or two before sleep time, such as listening to soothing music, watching the sunset, or counting stars.
  6. During colder months, wear socks to bed. Having cold feet is a common cause of waking up at night.
  7. Strive to be physically active for at least a part of your day. A regular exercise routine can help to promote restful sleep.

Editor's note: Do you have sleepless nights? Can't seem to turn your brain off, get to sleep, or stay asleep?

If you'd like to start getting consistently good nights of sleep, we have an audio CD called NightTrain designed to help you fall into a restful, continuous sleep.

Here's what I experience with NightTrain: "The sleep I've been getting with NightTrain has been so good that for the first time in my life the alarm clock actually rips me out of sleep. Before I'd always been conscious in some form before it went off. Now, thanks to NightTrain, I'm deep in REM or stage 3 or 4 sleep before the alarm clock rings."

Click here to get your ticket and climb aboard the NightTrain express.

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