Essentials: Sleep Toolkit for Optimizing Sleep & Sleep-Wake Timing
In a Nutshell
Morning sunlight exposure within 30-60 minutes of waking, combined with delaying caffeine 90-120 minutes after waking and using cold exposure or exercise, sets the circadian clock for optimal daytime alertness and nighttime sleep. In the evening, avoid bright lights after sunset, use hot baths to trigger core temperature drops, and keep the sleep environment cool to facilitate sleep onset. Behavioral tools like consistent sleep-wake times, strategic light exposure, and temperature management outperform supplements, which include magnesium threonate, apigenin, and theanine only as secondary aids.
These notes were generated by AI and may contain inaccuracies.
Regardless of when you wake up in the morning, body temperature naturally increases, which triggers the release of cortisol. Cortisol should reach its peak early in the day, right about the time of waking. To ensure this peak occurs early, view bright light, ideally from sunlight, within the first 30 to 60 minutes after waking.
There are neurons in the eye called intrinsically photosensitive melanopsin cells that respond best to bright light early in the day. These cells signal to the suprachiasmatic nucleus, a cluster of neurons over the roof of the mouth that sends electrical and chemical signals throughout the body, triggering the cortisol increase, providing a wake-up signal, and setting a timer for sleep later that night.
Instead of reaching for a phone, get out of bed and go outside. On bright clear days with low solar angle, or on cloudy days, get outside to receive as much light energy or photons in the eyes as possible. Do not stare directly into the sun. Never look at any light that is painful to view. For morning sunlight viewing, do not wear sunglasses. It is fine to wear eyeglasses or contact lenses, as these focus light onto the neural retina and melanopsin cells.
Hundreds to thousands of peer-reviewed papers show that light viewing early in the day is the most powerful stimulus for wakefulness throughout the day and has a powerful positive impact on the ability to fall and stay asleep at night.
If you wake up before the sun is out, turn on artificial lights if the goal is to be awake. However, bright artificial lights in the home are not sufficiently bright to trigger the cortisol mechanism and other wake-up mechanisms needed early in the day. The diabolical twist is that those same lights are bright enough to disrupt sleep if viewed too late at night or in the middle of the night.
There is an asymmetry in retinal and brain biology: early in the day a lot of light is needed, and artificial lights generally will not accomplish what is required. At night, even a little artificial light can disrupt circadian clocks. On cloudy or overcast days, get outside and get more sunlight.
On a clear day with minimal cloud cover, get sunlight exposure to the eyes for about 5 minutes. On days with cloud cover, get about 10 minutes. On densely overcast or rainy days, get as much as 20 or 30 minutes. Do not try to get sunlight exposure through a windshield or window, as it takes far too long and will not trigger the relevant mechanisms.
For locations with extreme darkness or overcast conditions, sunlight simulators or daylight simulators can be purchased. Cheaper alternatives include ring lights and LED tablets. Many people live in places where winter makes sufficient sunlight difficult, so morning light from sunlight should be prioritized while accounting for the specific points given.
Morning sunlight viewing causes the body to feel more energized more quickly. The diffuse, very bright sunlight and photon energy sets rhythms of brain and body properly. It triggers proper metabolism, sets a timer to fall asleep about 16 hours later, and suppresses melatonin that may still be circulating at waking. It also interacts with the adenosine system and can wash out residual adenosine if sleep was insufficient.
To increase core body temperature more quickly than shuffling around outside, use cold water exposure or exercise. A cold shower, ice bath, or cold tub for 1 to 3 minutes wakes you up via adrenaline release and increases core body temperature. A cluster of neurons in the medial preoptic area acts as a thermostat: when the external body is cold, the brain heats up core body temperature. Staying in cold water longer will eventually drop body temperature, but 1 to 3 minutes produces the increase.
One of the best ways to increase core body temperature early in the day is exercise. Research points to immediately upon waking as the best time to exercise. This can include a walk while getting sunlight, a light jog, or skipping rope. Exercise does not have to be the full workout for the day.
Everything done in the first 60 to 90 minutes of the day sets in motion biological cascades that carry through the entire day, evening, and night to optimize sleep.
Caffeine is an adenosine antagonist that limits sleepiness. Shifting caffeine intake from immediately after waking to 90 to 120 minutes later gives many people a longer arc of energy throughout the day without needing more caffeine in the afternoon. If drinking caffeine later in the afternoon, limit total amount or drink decaf, keeping total under 100 milligrams if interested in best possible sleep.
Papers show that caffeine intake after 4 p.m. can disrupt sleep architecture. Even if sleep feels fine, quality may be lower than if caffeine were avoided in afternoon hours. If main exercise occurs first thing in the morning and caffeine is desired beforehand, that is acceptable.
Eating early in the day supports a biological clock mechanism that increases alertness early. Many people fast until 11 a.m. or noon. If hungry upon waking, eating early further triggers an increase in metabolism and temperature that promotes alertness. Sunlight viewing, exercise, cold water, and eating all converge on the same mechanisms. Caffeine also produces a small increase in body temperature via adrenaline.
If eating a very large meal, a large volume of food diverts blood and resources away from the brain, causing sleepiness. Food volume is a strong parameter often neglected in discussions about eating for energy. Eating a huge breakfast is likely to cause tiredness afterward unless intense exercise beforehand metabolizes the food quickly.
Eating helps set a food-entrained circadian clock. Light, temperature, timing of food intake, movement, and exercise funnel into the circadian clock and allow it to predict when eating, activity, and sunlight viewing are likely the next day. These tools set up a cascade or wavefront of wakefulness and focus throughout the day.
There are three critical periods throughout each 24-hour cycle. The first critical period is from waking until about 3 hours after waking and includes morning sunlight, caffeine 90 to 120 minutes after waking, and exercise.
The second critical period spans the middle of the day through afternoon and evening. Be careful not to ingest too much caffeine during this time. Naps are fine in the afternoon but should not be so late or long that they disrupt the major nighttime sleep bout. There is no requirement to nap. If able to make it through the day without napping, that is acceptable.
Intense afternoon or evening exercise such as weight training or running increases body temperature and delays the circadian clock, making bedtime naturally later. Early-day exercise typically does not shift the circadian clock much.
Getting sunlight in the eyes for 5, 10, or 30 minutes in the late afternoon and evening at low solar angle inoculates the nervous system against negative effects of bright or dim artificial light between 10 p.m. and 4 a.m. This viewing signals that it is evening time and sleep is coming. The yellows, blues, and oranges of evening sunsets establish a second reference point or wavefront of biological signals that optimize nighttime hours and the transition into sleep.
Critical period three covers late evening from roughly 6 or 7 p.m. through bedtime and throughout the night. Avoid bright artificial lights of any color once the sun goes down. Dim indoor lights. When using light at night, use only as much as required to carry out activities safely. Dim television and computer screens as much as possible while still viewing what is needed. Bright light exposure quashes melatonin that is naturally released in the evening and nighttime hours.
A simple rule of thumb is to avoid bright artificial lights of all colors, and in particular overhead bright artificial lights, between 10 p.m. and 4 a.m. Use only as much light as absolutely necessary for routines and activities.
Temperature should be leveraged in the evening in the exact opposite manner from early in the day.
The way to leverage temperature in the evening is the exact opposite of the way that you want to leverage temperature early in the day. Early in the day, temperature increases from cold showers or exercise wake you up. Taking a cold shower late at night is probably a bad idea. Taking a nice hot bath, hot tub, or sauna in the evening for no more than 20 or 30 minutes, then getting out and taking a coolish or warm shower, triggers a compensatory cooling of your core body temperature. Your body temperature will drop by 1 to 3° and it will make it much easier to get into sleep. Evening and nighttime is the best time to do hot baths, hot showers, or hot tubs if your goal is to facilitate sleep.
Make your sleeping environment pretty cool, if not cold. This does not mean you need to be cold while you're asleep. You can get under as many blankets as you need, but it is a good idea to make your sleeping environment cool. Drop the temperature in that sleeping environment by at least 3°. If you lower the temperature in the room or use a controllable mattress cover that can cool down, it is naturally going to make your sleeping environment cooler. If you are too warm under the blankets, all you have to do is extend a hand or a foot out from under those blankets. If the sleeping environment is too warm, there is very little you can do to cool off besides push off those blankets.
Alcohol, THC, and CBD affect sleep. The sleep that one gets after drinking alcohol is greatly disrupted sleep. THC and alcohol do help some people fall asleep and maybe even stay asleep, but the architecture of that sleep is suboptimal compared to the sleep they would get without alcohol or THC in their system. If your sleep is not restoring you to the extent that you feel it should or if you are regularly relying on a drink or two or THC in order to fall asleep, that is disrupting your total pattern of sleep.
Behavioral tools come first, then nutrition, then supplementation if necessary, and then prescription drugs if still necessary, prescribed by a board-certified physician. There are supplements that for most people will greatly improve their ability to fall and stay asleep. The three main supplements in the sleep toolkit are magnesium threonate, apigenin, and theanine.
You do not necessarily need to take all three supplements. Many people get a synergistic effect from taking all three, while some people may not need any. If you are already doing all the behavioral tools regularly and you are still having trouble falling asleep and staying asleep, then you might try one of the supplements within this sleep stack. They have fairly wide margins for safety. Anytime you are going to add or remove something from your supplement protocol, talk to your physician.
For most people, the margins of safety on these things are going to be pretty broad. For some people, the dosages of any one or several of the supplements will be zero. For many people, taking 145 milligrams of magnesium threonate can be very beneficial. Some people need to go a little higher, some people need to go a little bit lower. 50 milligrams of apigenin can be taken on its own. 100 to 400 milligrams of theanine, taken alone or in combination with the other supplements, allows many people to get really drowsy, fall asleep really deeply, and feel much more refreshed the next day without grogginess.
About 5% of people report that magnesium threonate really disrupts their gut and gives them diarrhea or gastric distress. In that case, do not take it. Some people who tolerate magnesium threonate and like apigenin find that theanine, even at the lowest dose of 100 milligrams, gives them such vivid dreams that they find it disruptive. They wake up in the middle of the night or find that the sleep they are getting is anxiety-ridden because of the intensity of those dreams. Some people might choose to leave theanine out of the sleep stack and just take magnesium threonate or apigenin. Some people might leave magnesium threonate out of the sleep stack. All of this is about finding the supplementation protocol that is ideal for you.
The ideal time to take the sleep stack components is 30 to 60 minutes before bedtime. This sleep stack can be very beneficial and is preferable to melatonin. Melatonin is a hormone that you endogenously make. The dosages of melatonin contained in most commercial products are far greater than what we would make endogenously, so they are really supraphysiological. Melatonin is not just responsible for making us sleepy and fall asleep. It also interacts with other hormone systems, testosterone and estrogen, even in the puberty system in kids. Taking melatonin every once in a while for adjusting to jet lag is probably not a problem. Taking it chronically over time, especially kids taking it chronically, can potentially be problematic.
A broad contour tool that impacts the most number of people is weekends. Most everybody feels the impulse to sleep in on the weekend, especially if they have been out late the night before. Keeping relatively consistent sleep and wake times is really going to enhance the quality and depth of your sleep. If you stay out late one night, you might allow yourself to sleep in an extra hour or so, but try to avoid sleeping in longer than an hour beyond your normal wake up time. It would be better to wake up at a consistent time plus or minus an hour and get a nap in the afternoon provided that nap is not too long.
Jet lag can be due to travel or getting woken up in the middle of the night. The body does not know the difference between flying to a new time zone and getting woken up in the middle of the night. The temperature minimum is a time within your 24-hour cycle. Approximately 2 hours before your typical wake up time, your body is at its lowest temperature that it will ever be in the 24-hour cycle. If your typical wake up time most days is 7 a.m., then your temperature minimum is 5:00 a.m.
If you view bright light, exercise, or drink caffeine in the two to four hours before your temperature minimum, that will delay your clock. It will make you want to go to sleep later and wake up later the next night. If you get up at 3:00 a.m. or 4:00 a.m. and flip on bright lights, have a cup of coffee, or do any kind of exercise, the mechanisms that control timing of sleep and waking will delay. You will tend to want to go to sleep later and wake up later the following night.
The opposite is true if you view bright light, drink caffeine, or exercise in the hours immediately after your temperature minimum. For a person waking up at 7:00 a.m., if you view bright light, exercise, or socialize at 5:30 a.m., 6:00 a.m., or 7:00 a.m., that will tend to phase advance your clock. It will make you want to go to bed earlier and wake up earlier the following night.
This is an immensely powerful tool if you are headed to a time zone where you need to go to bed earlier and wake up earlier once you arrive. In the day or two before you leave, you can force yourself to exercise, drink caffeine, or eat a meal early in the morning to phase advance your clock. If you are traveling to a time zone where you are going to need to go to sleep much later and wake up much later, you can do those things in the hours prior to your temperature minimum.
If you need to be awake in the middle of your sleep cycle, use red light. For shift workers who are trying to stay awake all night and sleep all day, this is not going to be ideal. For people who need to stay up really late one night or wake up especially early, using red light has been shown to allow people to be awake enough to perform their activities safely but it does not seem to disrupt the healthy normal cortisol rhythm.
Get your behaviors right and get your nutrition right for you. If you start to implement some or ideally all of these tools, the quality of your sleep will increase tremendously. In doing so, the quality of your daytime alertness and your ability to focus will improve tremendously. Sleep is the absolute foundation of your mental health, your physical health, and your performance in all endeavors.
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