Re-Evaluating Priorities: Food vs. Sleep, by Jared S.

I was reviewing some back issues of the Journal of Wilderness and Environmental Medicine, published by the Wilderness Medical Society, and came across an article that I realized may be of use to preppers.  The article deals with the effects of food deprivation vs. the effect of sleep deprivation, on cognitive ability, decision making, and risk taking behaviors.  Here I will attempt to summarize the relevant findings and examine how these realities might inform our choices in prepping and responding to emergency survival situations. 

We have all been taught the easy to remember device for setting priorities for survival, right? You can’t live more than 3 minutes without air, 3 hours without shelter, 3 days without water, 3 weeks without food.  While this list has been examined and tweaked over the years to suit the uses and particulars of various groups, it remains essentially a fair, if imprecise rubric of priorities.  Except the food.  Studies have shown what reality has long known: when things get tough, people do not starve to death; they are killed or injured as a result of poor decision making (often related to trying to obtain food).  From a strictly starvation stand point, it takes far more than 3 weeks to die, but the poor decisions you make, whether in a moment of hunger or a prolonged calorie deficit, are much deadlier much faster.

Hunger isn’t the only stressor facing the would be survivor (doesn’t matter what the disaster–could be TEOTWAWKI, could be a wildfire/hurricane/tornado/ice storm/train derailment/etc.).  Lack of sleep,  whether caused by a need to remain vigilant (security threats, long haul driving) or insomnia related to mental stress or environmental stimuli, is a very real and very common reality in the days and even weeks immediately following disasters.  Back when I was a wild land firefighter, the feds would not let a crew work more than 18 hours in a stretch, no matter what the fire was doing, because after so many hours of constant wakeful work, reaction time was dulled to the point of being legally drunk (so I was told).  A crew must be taken “off the clock” and given a safe place to sleep, even if that place was 3 feet back of the fire line they had just been working on.  Better to let a crew sleep and loose a few steps on the fire, than push a crew past the point of fatigue and have to deal with the inevitable costs and casualties that come with high risk work and dulled perception, reaction time, and impaired decision making.    

Even if zombie squirrels ate every last protein bar and bit of hardtack in your BOB, you will not die of starvation on your 3 day (or 3 week) journey to safe haven.  What is much more likely to get you into trouble is making bad choices.  In light of this fact, the authors of this study wanted to determine which had the greater negative impact on decision making and cognition in civilian survival situations, lack of food, or a lack of sleep.  To do this, they examined the effect of food deprivation for 18, 42, and 66 hours and of sleep deprivation for 26 and 50 hours on blood glucose levels, simple and choice reaction time, memory/recall, risk taking, and navigating a computerized maze. 

The tests found that while food deprivation had the effect of increasing symptoms of low blood sugar (hypoglycemia), these symptoms where increased even more when deprived of sleep.  Reaction time was slower for both groups (food deprivation and sleep deprivation) in both simple reaction time (how quick you can perceive a change and react) and in choice reaction, which forces a choice between three actions when prompted.  Sleep deprivation of 26 and 50 hours was found to have a more deleterious effect that either 18, 42, or 66 hours of food deprivation.  Memory and recall tasks were both negatively affected to nearly the same extend for both groups, with the exception of delayed recall, which suffered a much larger (almost 50%) decrease after 50 hours of sleep deprivation.  Visual/spatial learning was also negatively affected by both treatments, again with sleep deprivation causing a more dramatic worsening of ability to navigate a computer generated maze.  Finally risk taking behavior was affected very little by food or sleep deprivation, with the exception that 50 hours of sleep deprivation decreased subjects risk tolerance, and both food and sleep deprivation cause subjects to make risk taking decisions faster. 

So what does all this mean?  Essentially given the choice between expending energy to procure food or toward procuring sleep, we should prioritize the sleep.  This of course is easier said than done.  In fact the authors even acknowledged that even small amounts of food may make sleeping easier.  “Sleep hygiene”, as it is known among those who counsel people with insomnia, includes things like avoiding caffeine after noon, not watching TV while lying in bed, keeping a consistent pre-bedtime routine, having a quiet, dark, cool place to sleep, and going to bed at the same time each night.  Good luck finding any of those things in the hectic days immediately following a major disaster.  So what to do?  For starters, be aware of what environmental factors are affecting our mood and decision making process.  By being aware that perhaps it is not only the stupid knot on your tarp shelter you can’t untie in the freezing rain at night that is causing your disproportionately angry feelings, but also the lack of sleep, you can compartmentalize the things that you can control and the things that you can’t, fix or improve what can be fixed, and prioritize what is important in the long run (sleep!) over the task at hand (untying that knot).  Finally, it may be worth considering some supplements to your emergency sleep hygiene plan.

Chamomile has been used for centuries as an herb that calms and promotes sleep, and is available in tea form at the supermarket right now.  Melatonin is also available over the counter, and used on an occasional basis by many night shift ER nurses, among others.  Benadryl (diphenhydramine) is the most common histamine blocker used to treat allergies, but its’ number one side effect is drowsiness.  In fact, the exact same drug in the exact some dose (diphenhydramine 25mg) is sold as an over the counter sleep aid, often cheaper than the same drug in a different bottle sold as an allergy blocker!  A brief warning, there is a very small percentage of people who have an opposite reaction to Benadryl and get a stimulant effect from the drug.  My mother is one such, who refuses to take it because she’ll be up all night cleaning the house and unable to sleep.  Of course there are also prescription drugs available to promote sleep, and while their action is different than those listed above, they share the warning that they are NOT for long term use, as they can cause a dependency that makes is difficult to fall asleep without them.  But as a useful addition to a disaster medical kit, I would certainly give them strong consideration.  Among these, the benzodiazepines such as Ativan, Xanax, and Valium are common, useful, and powerful, and have the added benefit from a survival medicine chest perspective of being anti-seizure and anti-anxiety drugs.  The down side is that they are also commonly abused and are controlled substances, which makes it less likely that even a sympathetic doctor will prescribe them “just in case”.  You may have better luck with the non-benzo hypnotics such as Sonata, Lunesta, and Ambien, which have less potential for abuse and are meant for short term treatment of insomnia.  In any case, never mix these drugs with alcohol (even the over the counter drugs), use the lowest effective dose possible to avoid over sedation and grogginess the next morning, and use only after consultation with a doctor (Disclaimer: nothing in this article should be construed as specific medical advice).

This is not to discount the value of food, as negative effects with food deprivation on performance were noted in the study; it is just that they were not as dramatically negative as the effect of sleep deprivation.  This study also cites other, prior published works that illustrate the negative effects of combined food and sleep deprivation, which of course is a real possibility in a survival situation, This study however was attempting to discern the relative contribution of each to the noted reduction in capability.  The study also cites prior literature dealing with the effect of hypoglycemia on cognition and decision making, and found it to have a greatly deleterious effect.  Even though in this study sleep deprivation was found to increase hypoglycemia symptoms, this study intentionally excluded those with diabetes or other confounding health problems.  For that reason, food would certainly be a bigger priority for those with diabetes, hypoglycemia, or other metabolic conditions.  Finally, the study authors also acknowledged that even small amounts of food may improve endurance and be critically important to preventing hypothermia in cold conditions.  All of these are valuable considerations for preppers.  Better to know why we do the things we do, rather than blindly following by rote the prescriptions of a variety of experts. 

Through better understanding we can be better prepared for unanticipated circumstances.  In particular it is an easy temptation for the strong (well prepared) member of a group to shoulder a bit more of the burden, to take that longer shift on watch, to hike through the night, thinking after all that it is only a little sleep you are missing out on.  But bear in mind it is not just sleep and comfort you sacrifice, but rather it is your keen edge in decision making, reaction time, and spatial reasoning that you give up.  Knowing this, you may be better prepared to appropriately weigh all priorities should you ever be faced with such a situation.

For those with an interest in reading the entire article, it is available to the public in the WEM archive here.  In addition to this article there are a variety of others on all kinds of topics related to emergency, wilderness, remote, expedition, combat, and improvised medicine.  Be aware, the details of some of these articles may be difficult for those who don’t speak “medical”, but the abstracts are generally very comprehensible.   The Wilderness Medical Society also holds several conferences each year, with expert speakers in many disciplines of medicine and hands on workshops on subjects like improvised splinting, litters, and orthopedic care, avalanche awareness and rescue, snow shelters and hypothermia prevention and treatment, and many others.  While these conferences are geared for medical professionals, there is no reason interested lay-persons (preppers) can’t attend and learn alongside the pros. 

Finally, a very reasonable standard of medical training for peppers would be Wilderness First Responder, an approximately 80 hour program that goes much deeper into prevention, assessment, treatment, and ongoing management of the sick and injured with an emphasis on austere environments, limited resources, and improvisation.  Numerous schools with some excellent instructors include Wilderness Medicine Institute, Aerie, SOLO, WMA, and others.  A quick search online will locate a school near you.  Given that fracture/laceration/heart attack type “disasters” are much more common than EMP/hurricane/asteroid type disasters, the wide spread dissemination of a useful level of medical training makes all of us safer.