Why Can’t I Sleep Even Though Exhausted? Solved.

circadian rhythm sleep Dec 20, 2022

It's 10 PM. You start to yawn and your eyelids weight more than before. Bedtime. You roll into your bed but as soon as your head hits the pillow, you feel awake again. If this sounds familiar to you, then your nervous system may be too alert.

This article lists 15 reasons you can't sleep though you're tired and what to do about them. 


1) Blue and bright light in the evening


The brain starts preparing you to sleep from the moment you wake up. This is when the holy trinity of sleep-related hormones start their rhythmic patterns: cortisol, adenosine, and melatonin. Your affect their rise and fall with your daytime habits. And whether they rise when they should. Cortisol is the sleep-preventing hormone that rises in the morning to wake you up and should be low in the evening

Melatonin should rise in the evening because rise in the melatonin levels signals the body that it's time to sleep. However, modern artificial lights pose a risk for this process because they affect brain areas that regulate melatonin.

Light affects sensors in the eyes retina which relays a message to a brain's pineal gland that interprets environmental light and regulates hormone production. Blue lights, led lights, and bright lights prevent melatonin production because they resemble daylight and the brain interprets that it's time to stay active. 


How to block blue light?

Studies confirm that wearing blue light blocking glasses after 6 PM help to preserve the normal melatonin production in environments that have blue lights. Blue light is emitted by normal ceiling lights, computer screens, phones, TVs, street lights, office lights, gym lights, and store lights.

In one study, red light treatment in the late afternoon for 30 minutes over 14 days increased melatonin and improved sleep in female athletes. 



2) No morning sunlight


It’s important to see sunlight in the morning because it initiates the rhythm of melatonin production in the brain. The brain prepares to produce melatonin about 14-16 hours after being exposed to the morning sunlight. Missing this critical time period of seeing the sun may prevent the brain from producing enough melatonin in the evening. Morning sunlight has also shown to improve cognitive performance at work. It's important that it is the sunlight instead of indoor light because sun (or sun mimicking light device) is the only potent enough potent light source to initiate this rhythm.

Morning sunlight for circadian rhythm and sleep

Get exposed to morning sunlight immediately after waking up. It needs direct sunlight outside or through an open window, because glass reduces its efficiency significantly. If it is a cloudy day, you need about 15-30 minutes of outdoor exposure, suggests a neuroscientist Dr. Andrew Huberman. But on a sunny day 5-10 minutes is enough. Those who live in the Nordic countries and don’t have sun in the morning, can use a Seasonal Affective Disorder Light device that mimics the sunlight (with a minimum of 10 000 lux).


3) You're too alert


It’s essential to activate the  “rest and relax” (parasympathetic) nervous system in the evening. If you find it hard to relax, you may have too much stimulatory neurotransmitters and stress hormones in your system and need some additional tools to increase the relaxing neurotransmitters like GABA. Some supplements can support this process.


Best supplements for relaxation


4) Not enough tryptophan


If you don’t get enough tryptophan from your food, your melatonin levels might be lower. Amino acid tryptophan is a building block of protein and also a building block of melatonin and serotonin. Brain melatonin levels correlate with how much you get tryptophan from your diet and if you don’t eat tryptophan-rich foods you may naturally be producing less melatonin. 


Tryptophan supplement and tryptophan foods

Eat tryptophan-rich foods daily to ensure proper melatonin production. These include pumpkin seeds, oats, banana, turkey, chicken, and dairy

Try a 500 mg - 1g of tryptophan supplement taken with some carbohydrate like banana or oat to increase its uptake. Don’t take other proteins at the same time because they can slow down tryptophan delivery to the brain.


5) Not enough adenosine


Adenosine is a hormone that accumulates in the brain during the day to increase sleep pressure. It’s created in the brain as a byproduct of using energy. Adenosine builds up more when you consume more energy, for example during exercise. If you accumulate too little adenosine during the day, you don’t build up enough sleep pressure to make your body fall asleep. Exercise is an efficient way to build up adenosine, because it uses a lot of exercise.


How to increase adenosine?

Studies show that exercise is clearly linked to next-night sleep quality and quantity. In one study, each 1-hour of exercise helped people to fall asleep 18 minutes earlier and sleep 10 minutes longer.


6) Eating dinner too late


Your gut is optimized to digest food when you’re the most insulin sensitive, which is usually during sunlight and after exercise. The digestive efficiency of the body starts declining after sunset or a few hours before your bedtime. Eating too close to bed decreases the efficacy of sleep related processes, increases energy levels, and increases blood sugar which disrupts sleep rhythm. 


Intermittent fasting benefits

Studies show that early time-restricted eating, or stopping eating at least 2 hours before bed, increases sleep duration and quality, benefits metabolism, and supports optimal circadian rhythm. 


7) Worry


Worry sometimes creeps into mind the moment you close your eyes. Looping thoughts of worries can increase anxiety and prevent you from relaxing. There are a few ways to prevent this situation from happening


How to control anxiety and worry in the evening

  • Focus on positive thoughts in the evening. Focus on evening activities that expose you to positive thoughts; don’t read news or go check social media profiles or channels that are negative or provocative.
  • Play with the family. Try something that makes you all laugh and relax with each other. This can help you to forget stressful thoughts and be more mindful.
  • Write a worry journal. If your mind drifts to worry thoughts just before bed, write the worry ideas down, like transferring them into an external harddrive and releasing them from your head. Worries can sometimes  get bigger inside our head than they are in reality and this method helps you gain perspective to them. It also helps you to make a “mental note” on a situation that you can return later, after you slept. It’s best to focus on sleep first, and solve problems with a rested mind and more energy. 
  • Write a gratitude and success journal. Write down one or two things that you’re grateful for and things went well today


8) Too hot room 


Body temperature drops in the evening. This physiological mechanism activates the parasympathetic nervous system that helps you to fall asleep. Thus, if the body, or the room you sleep in, are too hot, you may have trouble falling asleep. Try these strategies to fall asleep faster


Optimize your bedroom

  • Cool your bedroom to 18-22 °C or 64-69 °F
  • Take a cool shower before bed. Avoid too cold showers so you won’t get stressed. 
  • Avoid heavy exercise 4 hours before bed because that increases body temperature
  • If it is cold outside, keep the windows open in the bedroom before bedtime to cool down the room
  • Try a cooling mattress like Eight ssleep
  • Prevent elevated body temperature with natural bedding materials that breath (like cotton or bamboo)
  • Take 3 g of glycine 1 hour before bed. Glycine lowers body temperature and increases calming neurotransmitters.


9) Mold in the bedroom


Do you sleep in moldy room? Dampness and mold at home are linked to difficulties in falling asleep and staying asleep, as well as insomnia, snoring, and waking up too early. Mold particles spread in the indoor air and can cause low-level allergic reactions, irritability, and inflammation in the body.

Mold accumulates especially in moist conditions to inside the walls and ceiling, and to natural materials such as wood and paper. So if you found suspicious black spots or dusty odor in the wallpaper, wooden furniture, books, cardboard boxes, or such, remove them from the bedroom.


How to improve indoor air quality

  • Scan your bedroom for any visible mold and wash it
  • Remove all mold-smelling books, cardboards, and furniture from the room
  • Get an high-quality airpurifier that cleans mold particles in the air
  • If you suspect larger mold problem, get a mold assessment, and consider professional cleaning


10) Caffeine in the circulation


Coffee has a lot of antioxidants and drinking a few cups of it each day has shown to protect from memory diseases. It can also energize and boost performance, especially after sleep restriction.

However, drinking coffee in the afternoon might be detrimental to your sleep because it blocks the adenosine receptors and increases wakefulness. Importantly, caffeine does not immediately leave your body. It takes about 10 hours to remove caffeine from the blood. This also depends on the condition of kidney, liver and genetics. 

But if you drink coffee at 4 PM, most likely 50 % of that caffeine is still affecting your brain at 9:00 PM, which can prevent you from falling asleep. 


Caffeine half-life and sleep

Since caffeine half-life is about 5-7 hours, stop consuming coffee at noon to get your body de-caffeinated before bed. If you do, however, need an extra energy-boost during the day and need caffeine to clear out faster, consume extra vitamin C and brassica vegetables.


11) Vitamin D deficiency

If you lack sunlight or don't get enough vitamin D from the diet or supplement, your sleep may suffer. Studies link vitamin D deficiency to sleep disturbances, short sleep and decreased sleep quality. The brain sleep-regulating pathways has a lot of Vitamin D receptors and thus the levels of vitamin D effect sleep regulation.


Should you take vitamin D? Vitamin D test

Make sure your vitamin D levels are normal by doing a vitamin D lab test. If they are too low, you may need to get more sunlight exposure which is the most bioavailable form of Vitamin-D. Midday sun is the best because during the midday the UVB rays are the most intense. One study found that during the summer, UK adults reach sufficient (though not the optimal) vitamin D levels by exposing 35 % of body surface to the midday sun for 13 minutes 3 times a week. In the winter time, when there is less sun and more darkness, you may need a vitamin D supplement.


12) Bad bed or pillow


Old, sagging mattresses have shown to negatively affect sleep quality. Similarly, it’s been shown that there are individual differences on the most optimal mattress firmness for each sleeper.


Ergonomic bed

Upgrade your bed and pillow for ones that are ergonomic and supportive. A study showed that orthopedic pillow was superior to sleep quality and night-time body temperature compared to feather pillow or memory foam pillow


13) Electronics in the bedroom


Psychologists and sleep experts recommend to sanctify the bedroom and especially the bed for sleep and love only. Having work-related memory cues (such as laptops, notebooks, or phones) in your room can activate thoughts of work and prevent relaxation. Lights and electromagnetic radiation can similarly alert the nervous system.


14) Sleep problems before and during period 


Women may have sleep issues especially before and during the period due to drop in female hormones, especially progesterone. Progesterone breaks down to ALLO which has a soothing effect on the brain by increasing a calming neurotransmitter called GABA. When progesterone drops before period, women may feel less sleepy and more nervous. All major female hormones affect brain areas that are also involved in sleep regulation and circadian rhythm. Women with PMS are twice as likely to have sleep issues before period.  


Hormonal balance and sleep

If menstrual sleep problems get severe, consider consulting a female hormone expert or a functional doctor who can recommend supplements related to your specific sleep issues. Track your hormonal cycle and see if there is a patterns between your cycle and sleep. Know that hormone-related sleep issues tend to balance when hormones balance. 

Listen this episode on hormones and sleep


15) Hormonal imbalance

All major hormones from sleep hormones to thyroid and sex hormones can affect sleep patterns in different ways. We've already talked about melatonin, cortisol, adenosine and sex hormones. Similarly, low thyroid hormones and testosterone can cause sleep disturbances.


How to balance hormones naturally?

The first step is to measure your hormone levels and live a balanced, healthy lifestyle that support overall hormonal balance. It's important to maintain circadian rhythm with aligning light exposure correctly and not eating too close to bed. Balancing blood sugar also helps with hormonal balance. In this episode, a medical doctor and hormone expert Dr. Carrie Jones, tells how hormones affect our sleep, mood, and behaviour, and how to balance hormones naturally. 

Subscribe and watch here:


What to do if you're sleepy but can't sleep

If you wake up during the night and are fully awake, just focus on your breathing and wait for a bit. Usually you fall asleep in 20-30 minutes and resist the urge to crap your phone and stimulating your mind. You probably will fall asleep again soon. Avoid thinking when it will happen, or getting frustrated or anxious about it. Just keep calm and relax.

However, if the sleep has not arrived in 30 minutes or so, get out of the bed, but keep lights dim and use blue light blocking glasses to avoid any light-stimulation. Do something that helps you to relax and go back to sleep only until you feel sleep again.


When to see a doctor

If you suffer from sleep problems for a long time without getting any catch up sleep in the weekends, consult a functional doctor or a sleep coach who can assess the reason and make you a sleep program or recommend supplements. Even one week sleep deprivation for 6 hours per night can lower immunity and cognition, but catching up on sleep on the weekend can normalize it. So if you have had a rough week with little sleep, don't feel bad of sleeping long on the weekends. It'll be good for you.


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