Posted on April 29 2016
Most of you reading this will have put high effort into determining just the right equipment for your outdoor pursuits or survival equipment inventories. To you, it is likely a knife isn’t just a knife, but a prized possession that you find fits your hand perfectly and is best suited to the tasks you require. Once you have researched and selected the gear to cover the ‘survival priorities’, you will almost certainly have some food supply. Even in tiny ‘grab and go’ packs, such as kits built around the Snugpak Response Pack or similar bags, there is space for at least some food.
Food, while not an immediate survival priority (such as shelter, warmth or water), is still imperative at times when your body needs a lot of energy to stay warm and function correctly. In an outdoor activity you will likely be burning a lot more energy than most people do at home or work, and if the event turns into a desperate hell march back to safety, especially in cold and wet weather, then your energy requirements can be 5 or 6 times standard.
The body has energy reserves
Humans, in comparison to many animals, carry a large store of adipose tissue A.K.A. fat, which would have been a vital sanctuary to our hunter ancestors. Many people may point out that these fat reserves can keep you alive for weeks without food (I have a good size ‘survival belly’!). While this is true to some degree when going from a well-fed state to a starved one the muscles and liver will quickly become depleted of glycogen (the compound in which the body stores glucose ready for short term energy release). Fat burning and replenishing these glycogen stores through a process known as ‘gluconeogenesis’ takes a little while for the body to ‘switch on’ and until it does, your body will be sluggish and your mind dull. Not what you want in a survival scenario!
The right type of food
Unless you are lucky enough to be in an area with plenty of natural and easy to find food, obtaining enough calories from nature is an often understated great challenge. Therefore, a decent survival kit should always contain food.
Food is just food and as long as it contains calories it’ll do, right? Not really!
I can make the point of how you’d feel after scoffing an entire selection pack of chocolate compared to eating a well-constructed meal of the same calories as the chocolate. The human body can use fats, carbohydrates, proteins and even alcohol as energy (unless you are a pirate, the last one isn’t recommended as a fuel source). Fat contains the most calories per gramme at around nine calories per gramme with carbohydrates and protein both containing around four calories per gramme. Fat is clearly the most energy-dense source with a set weight having over double the energy of carbohydrates or protein.
So the ideal survival food to carry is a block of lard? No; remember above I mentioned the body’s glycogen stores?
Glycogen is the store of glucose and is released for short ‘bursts’ of energy and providing the brain with a steady glucose supply for optimal function. Carbohydrates are far more efficient at keeping glycogen stores topped up than fat or protein (which both require ‘breaking down’ and going through various metabolic pathways before they can be stored as glycogen)
So we should include some carbohydrates in our food supply.
Blood sugar, and glucose vs. fructose
The simplest and easiest to digest carbohydrate is glucose; this can be absorbed quickly and used as a straight fuel source by every cell in the body. Sugar (sucrose) is a mixture of glucose and fructose (fructose also comes by itself, often found in higher concentrations in honey and fruits). Fructose is metabolised in the liver and not directly used by the body’s cells so is less than ideal than glucose for a survival situation where digestion or liver function may be impaired.
Good old Kendal Mint Cake is a time-honoured outdoor energy booster famously eaten on the peak of Mount Everest by Tenzing Norgay and Sir Edmund Percival Hillary. It is made with a good proportion of glucose syrup and is a great quick energy booster when you are feeling ‘drained’. However, it is important not consume too much glucose in one ‘hit’. As the body responds to large influxes of glucose by releasing lots of insulin (the hormone the body uses to ‘store’ blood sugar); this can create what is known as ‘reactive hypoglycemia’ or more commonly a sugar crash. Too much sugar can also irritate the digestive tract, so you should consider including some other sources of carbohydrate to prevent this; a flapjack containing oats for example.
In short term survival situations carbohydrates can help keep you moving and thinking quickly.
As mentioned earlier fat has a high energy density, so should be included as part of survival nutrition to pack more power into a smaller and lighter space. But fat isn’t just fat and there are many different types (also known as triglycerides). Don’t worry; I will not bore you and go into those various kinds but there is one type of fat fuel that stands out for survival purposes: Medium-chain triglycerides (MCTs).
MCTs are far easier for the body to digest than many other types; they do not require bile salts for digestion and passively diffuse into the GI tract without requiring energy, ideal for any situation where your digestive system has been compromised and every calorie counts! Due to their natural absorption and metabolism, they help promote the body to burn fat and produce heat.
Typically coconut and palm kernel oils contain larger quantities of MCTs. Those of you who like to bake your hiking flapjacks may consider including some coconut oil in your next batch.
Protein (made up of amino acids) is necessary for life and building muscle but is not much of a priority in a short term survival situation; just a small amount for keeping you ticking over is fine. In a long term survival situation, essential amino acids would be required for your body to continue functioning. But we will presume that if you’ve survived long enough for that to happen, you would have used your rations a long time ago and learnt how to hunt for food and thus have a supply of protein.
Protein is, of course, another source of energy and any food that swims, flies, crawls or walks will contain a good proportion of protein if you are lucky enough to catch it!
So, carbohydrates, fats and protein are all sources of energy and known as ‘macronutrients’. The other side to nutrition are the ‘micronutrients’, and these are the vitamins and minerals in foods that are required in small quantities for normal functioning. Some of these are less important for short term survival situations as the body has stores of some that will last months, we will not cover those here. However in situations where you are sweating lots, it will be important to have food that contains electrolyte salts to replace those lost through sweat and prevent a dangerous situation where your muscles will start cramping up.
A simple solution to this is to carry rehydration salts to mix with water and keep these minerals topped up.
Another useful micronutrient in a survival situation is B vitamins, which help the body release energy from food and keep health and wellbeing together when under high stress. Carrying a good multivitamin or B vitamin complex is a lightweight way of ensuring you have these.
Putting it all together
So, with all the above said, what should we take with us? What will make for a high-energy food source for outdoor activities and, should the worst happen, a reliable emergency food supply?
Shelf live and taste are also critical; you don’t want to pack anything that will taste like an old shoe, and the last thing you want in a survival situation is squatting in the midst of nowhere with a hard case of the ‘Barry Whites’ from food that has gone rancid. Another crucial factor is not carrying anything that requires cooking; I can’t imagine much making a survival situation worse than having to crunch through a pack of uncooked spaghetti.
As mentioned earlier, making a flapjack (made with oats, syrup and fat) is a pretty good hiking food for short trips, but for a survival kit that needs to stay ready in your bag for years you need items with a longer shelf life. Military ration packs are a good starting point, designed to be lightweight, high calorie and with a long shelf life (I once ate a British ration pack that was over 13 years old without a problem, although the ‘biscuits brown’ were even more like cardboard than normal). Civilian MREs are also good, but try to select the most energy dense ones, by looking at the energy per 100g on the packaging (most seem to be about 140kcal/100g). There are specialised ‘survival foods’ available such as Seven Oceans Emergency Food Ration Liferaft Survival Biscuits. They aren’t exactly gourmet eating but they are ready to eat and pack an energy density of 500kcal/100g!
There are also some exciting high energy choices in the Eastern European food markets or supermarket sections, including various lightweight foil or plastic containers with what is essentially pork or goose fat spreads within, called ‘smalec’. These are very nice when eaten with some long life crackers. Various other great life foods can be sourced from the supermarket, but it is important to go for foil pouches instead of tins for weight saving and ease of packing.
As previously noted, a source of glucose allows for a quick replenishment of energy and as well as Kendal mint cake many energy tablets contain mostly glucose, and the bonus of some of these is they also contain B vitamins. Chocolate is a mixture of fats and sugars, and thus a very dense energy source. Chocolate is not ideal for warmer climates for obvious reasons and you should go for a chocolate bar that contains more glucose, but there is something to be said for the morale-boosting nature of a bar of chocolate! I would urge you to try out various ration packs, civilian hiking foods and have a good scout around the supermarket for lightweight pouches and foil containers of foods.
What is your favourite food to keep in your hiking kit or bug-out bag?