There are several everyday consumables that may affect sleep latency or alter the amounts and depth of the sleep types. While monophasic sleepers may be less susceptible to these, polyphasic sleepers do have to consider these factors and possibly change their lifestyles in order to succeed with their adaptations. This article details several examples of such substances and their effects on the body.


Caffeine has a half-life of around 5-6 hours1 and will mostly be gone from the system after around 12-18 hours. It can still affect you depending on the initial amount consumed, however. It works by competing with adenosine for the same receptor type, which can lead to reduced drowsiness. However, it also has some other effects, including increased heart rate2, increased sleep latency, and reduction in sleep quality3. The increased sleep latency is particularly detrimental for polyphasic sleepers. For example in one observed case, after consuming a moderate amount of coffee and caffeinated soda around 3 hours before sleeping, the sleep latency appeared to be considerably impacted, requiring half an hour to fall asleep and almost an hour to reach NREM2 as reported by an Olimex OpenEEG – despite being sleepy.

The general consensus within the polyphasic sleeping community is to completely remove caffeine from the diet. However, this is likely to lead to caffeine withdrawal symptoms for people who have been consuming caffeine for a long time, because the body responds to the constant caffeine supply by upregulating (increasing) the adenosine receptor count4. That leads to a long-term tolerance and dependence on caffeine. For this reason, it may be favourable to first spend several weeks on regular (or even extended) sleep schedule to complete the withdrawal process before starting adaptation if you plan on removing caffeine from your diet.

It should be noted that Puredoxyk mentions in her Ubersleep book that she was given soda to stay awake during her initial Uberman adaptation, and has been known to drink small amounts of coffee and other things while sleeping polyphasically. It might also be beneficial to use small doses of caffeine to offset sleep deprivation symptoms during an early period of adaptation or during the initial sleep deprivation period. One trick often suggested is a “caffeine nap” where you consume caffeine immediately before sleeping. This is normally not recommended, as caffeine metabolism is fairly fast5 when consuming caffeine in liquid form. This can be avoided by use of caffeine tablets which generally have delayed onset. Due to the long half-life of caffeine, future sleep sessions can be impacted especially if the spacing between sleep blocks is short. For this reason, caffeine naps should be used sparingly and only when absolutely necessary and you may choose to refer to later parts in this guide for alternative methods to stay awake.

Decaffeinated coffee and similar drinks are not actually caffeine free. The decaffeination process used to make decaff only removes between 70 and 86% of the caffeine in reality6. The only schedule where moderate amounts of caffeine consumption should be okay is segmented, where drinking a cup of coffee in the morning should not hurt the quality of sleep during the night.

Caffeine is present in several products, and restricting consumption of these to a certain degree is wise. Some products that include caffeine are:

  1. Coffee (high caffeine content)
  2. Decaffeinated coffee (low caffeine content)
  3. Black tea (moderate caffeine content)
  4. Green tea (low caffeine content)
  5. White tea (negligible caffeine content)
  6. Dark chocolate (high caffeine content)
  7. Milk chocolate (low caffeine content)
  8. Energy drinks (moderate caffeine content)
  9. Sodas (varying caffeine content), caffeine free sodas include but are not limited to:
    • Caffeine free diet coke
    • Sierra mist
    • Sprite
    • Seagram’s ginger ale
    • A&W root beer
    • 7-UP

A rough estimate of caffeine content per 100ml (or 100g): negligible = 1 mg, small = 15-20 mg, moderate = 30-40 mg, large = >60 mg. Even the products with small amounts of caffeine should preferably be avoided, since they can still affect you if you consumed in large amounts, or if you’re sensitive to caffeine. The point after which caffeine will noticeably start affecting you is highly individual. Some people have very low thresholds of under 10 mg, while others have very large thresholds of up to 600 mg7. The positive effects from caffeine wear out before the negative ones. This results in an energy low which increases the chance to oversleep, while still preserving the negative effects on sleep.


It has been observed that alcohol consumption can increase depth and length of slow-wave sleep (along with the SWS need), and large amounts (more than 1 or 2 drinks) can lead to REM reduction. Drinking significant amounts of alcohol also leads to significant sleep architecture disturbance, which can completely wreck a polyphasic adaptation, increasing the risk of waking up during REM or SWS8. Consequently, it is not advisable to drink huge amounts of alcohol while sleeping polyphasically. It is also not advisable to drink alcohol prior to any sleep sessions which are intended to be REM-focused. It may be okay to drink a small amount prior to sleep sessions which are focused on SWS without significant schedule damage, but large quantities are not advised and avoiding drink entirely is probably the safest option. Ending consumption 2-3 hours before a core, then drinking a lot of water with a snack, can help minimize harm to sleep quality.

The amount of alcohol that can be consumed after adaptation depends on how strict and difficult the schedule is and how frequently it happens. Be cautious and test in small increments.

Smoking / Nicotine

Nicotine is a stimulant with similar effects to caffeine. It has a half-life of around 2h9, after which it is metabolized into cotinine, which is also a stimulant, and has a half-life of around 19h10. Consequently, it is likely that smokers will have harder time adapting to a polyphasic schedule as the sleep latency is increased and overall sleep efficiency is decreased11. So far, there are no reports of any smokers having successfully adapted to any schedule.


A very limited amount of research has been done with regards to cannabis affecting sleep. Research and anecdotal evidence points to cannabis reducing the amount of REM sleep and increasing the amount of SWS (possibly also increasing the SWS daily need)12. Because of this it should be avoided during adaptation, and consumption should at least be kept at a moderate amount after adaptation. Cannabis also seems to help with the speed of falling asleep, but adaptation still needs to take place.


It is best to avoid all drugs that alter sleep directly (by altering the sleep architecture, the relative proportions of sleep stages or increasing alertness or sleepiness), or indirectly (by inducing loss of self-control). This is especially important during adaptation as you may need to stay awake through periods of extreme tiredness. To better understand whether and how a particular (prescription) drug could affect your sleep, research half-life, effects on sleep, your mood and control from studies and provided information labels. If you’re unsure about consumption of a certain drug consult appropriate medical specialist regarding its effects and possible side effects, or ask in the Discord community chat server or reddit regarding experience of other users of the same or similar drug.


Melatonin may be useful for setting core bedtime earlier or later than it has been, just like its common use for jet lag. This is especially useful for setting your circadian rhythm on the first 1-4 days of your new schedule.

For polyphasic sleepers, it is recommended NOT to use extended time-release melatonin, as those are designed for mono-length sleeps. Typically only take for a few nights at a time. Amount of melatonin effective will vary per person, and overshooting the amount needed should be avoided, as it will make waking up very hard.   Toxicity of melatonin is known to be extremely low, but common doses range from 1-5mg, or 10mg in rare cases. Using melatonin for long periods of time is not recommended. It is best to teach the body to produce its own melatonin rather than relying on external sources. Melatonin should also not be used for the naps.

Main author: Crimson

Page last updated: 28 October 2019

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