Carbohydrates and Sleep
Growth hormone and insulin have antagonistic effects: Elevated growth hormone levels will reduce insulin’s effectiveness, and high insulin levels will suppress the secretion of growth hormone. Therefore, repeatedly eating carbohydrate-rich food immediately before going to sleep may impair growth hormone secretion during your deep-sleep phase. Additionally, your body is more resistant to the effects of insulin at night, meaning that you must produce more insulin to move a given amount of glucose to your body tissues. This may lead to even further suppression of growth hormone secretion.
Growth hormone secretion is an important part of the process of SWS, therefore going to bed with elevated or rising insulin will reduce the effectiveness of SWS that night. It is important to go to bed with low blood sugar so that you can maximize your growth hormone secretion potential and Slow Wave Sleep quality.
Originally, there was a number of papers showing insulin increasing deep sleep, for example here and here. The obvious statement, then, is that if carbohydrates increase insulin then naturally carbohydrates increase deep sleep. This is a prime example of an ‘affirming the consequent propositional fallacy’. While healthy metabolism will raise insulin in response to an increase in carbohydrates, a healthy metabolism will not raise carbohydrates in response to an increase in insulin (glucagon does that). It, therefore, stands that carbohydrates do not necessarily increase deep sleep, and in fact insulin will lower blood-glucose causing hypoglycaemia when increased alone…
A simple increase in ketosis or food restriction replicates this increase in SWS without decreasing Growth Hormone secretion. In fact, both low carb, ketosis and food restriction increases slow-wave sleep so much that there is little doubt that it is simply a lowering of blood sugar that increases slow-wave sleep, considering they all require low blood sugar to become functional, and food restriction means cellular energy uptake is minimal while leptin is low.
Controlled Ketosis increases both SWS and REM, whichever is deficient
Ketosis has been shown to increase SWS in SWS deficient people as seen above, but Ketosis also increase REM in REM deficient people.
Food restriction (fasting) is not a very good way to increase deep sleep because it is unpredictable, irregular, and the effects depend on the diet you are restricted from (eg HC vs LC before the fasting). However, food restriction in certain parts of the day may be beneficial for wakefulness and sleep depth at night.
Being completely ketotic can mean a reduction in REM below that of which is recommended, and so we, therefore, suggest a controlled ketotic diet. REM sleep requires the uptake of glucose in the brain, therefore by having a few carbohydrates before REM sleep (such as before a nap or a REM core sleep) you may improve your REM sleep without interrupting your ketosis. People have been known to kick out of ketosis at the start of the day and then enter back into ketosis by the end of the day, and this could be a possible solution to maximizing sleep stage quality.
Eating a low carbohydrate diet will mean increased REM and SWS and in conjunction with polyphasic sleep, less overall sleep will be needed.
Therefore, while a ketotic diet is most beneficial to sleep quality, this does not mean you should stop eating your fruits and vegetables, in fact, fruits and vegetables have their own special benefits as explained below.
Fibre and Sleep
A raw vegan diet was made popular by Puredoxyk and Steve Pavlina when polyphasic sleep was first evolving as a concept, and it has been attributed to their successful adaptations. It is no surprise that raw diets have evidence supporting their helping human sleep.
Vegan, Vegetarian or Carnivore aside, eating lots of raw vegetables can have many wonderful benefits for the human body by offering the gut ferment-able fibre. There is ongoing research into the hypothesis SCFAs created from the fermented soluble fibre reduces the requirements for REM sleep by saving developing oligodendrocytes from death by apoptosis. This means with higher effective SCFA consumption, you will need to sleep less, just as increasing SWS from ketosis means you will need to sleep less.
Raw Food and Sleep
Minimizing your cooked food intake is likely a good nutritional optimization simply because uncooked foods digest in 1/3 to ½ the time of cooked foods and food digestion distracts the brain from the sleeping process.
Food Nutrient Density
Minimizing risk of deficiency is important, as many nutrient deficiencies such as those of magnesium, zinc, calciferol, tocopherols, tocotrienols, retinol, EPA/DHA, choline, iodine, and B vitamins all increase the risk of sleeping disorder or reduced sleep quality. Eating from a selection of high-density foods definitely helps.
Examples of high nutrient density foods are:
Food timing can help with the regulation of wakefulness in a polyphasic sleeping pattern. It is ideal to eat when you expect to be awake. If you are starting a schedule, you should eat within 30 minutes of waking up, to increase the waking/hunger response post-sleep. Gastric juices will start to be produced at that time of day, which increases wakefulness.
If you have established a sleeping pattern then you should shift your eating pattern so that you eat in the middle or the end of a period you spend awake, with the one exception of before an SWS core sleep (you should not eat within 2-3h of this sleeping period).
The liver has a clock that will signal to the body that it is day time when it detects decent amounts of glucose. Carbohydrates should be consumed at the start or the middle of the day when there is daylight.
One factor is that at each meal, blood levels of cortisol NORMALLY temporarily triple regardless of macronutrients in the meal. Many people think that only dietary carbs do this but this is not true. Therefore we want to avoid eating too close to a time when we want Slow Wave Sleep (where sleep interruption is wanted the least!) This is why we say not to eat within 2h of a scheduled dusk core sleep for optimal sleep quality.
Another factor is because “gastric emptying is slow during sleep but the REM sleep is associated with faster gastric emptying.” Therefore you should aim to eat faster-digesting foods (raw food or raw meat) instead of slower digesting foods, and while you can eat before REM sleep, you should not eat for 2-3h before an SWS core sleep.
Currently, we do not advise any specific diet because the diet is a personal thing that revolves around ethics as well as health. There are threads discussing the many different diets.
Less specifically: Ketogenic Nutrition and Nutrition General
More specifically: Paleo Nutrition, Vegetarian Nutrition and Vegan Nutrition.
Example Meal Plan
If you have no preference for an eating style (paleo/veg/SAD) but want to improve your sleep without too much confusion you can follow this example meal plan. Eat 3-4 times a day, spread out across your schedule, with at least one 8h fasting period.
– 4 AM Eat seafood (salmon) and full egg olive oil mayonnaise with a side of oysters
– REM core sleep
– 8 AM Eat lots of raw low carb vegetables, fruits and bran (olives, avocado, coconut, spinach, oat bran, etc)
– 12 PM Eat lots of raw low carb vegetables, fruits and seeds (chard, fig, kale, broccoli, chia, etc)
– Midday Nap
– 6 PM Eat rare or slow-cooked fatty meat, offal, cheese, eggs and almonds
– SWS core sleep
Hopefully, this simple meal plan will not require stringent counting calories, has variety, and is simple to follow.
There are many different things to consider when optimizing your diet for polyphasic sleep, but ideally, you should eat a low carbohydrate, high-fat diet, that will include lots of digestible fibre and lots of fast-digesting raw foods.