Except for the water they drink and the oxygen they breathe, IP must meet their physical needs through the intake of food. This chapter will explore the relationship of proper nutrition to physical and mental efficiency. It is extremely important that IP maintain a proper diet at all times. A nutritionally sound body stands a much better chance of surviving. Improper diet over a long period of time may lead to a lack of stamina, slower reactions, lower resistance to illness, and reduced mental alertness, all of which can cost IP their lives in a survival situation. Knowledge of the body’s nutritional requirements will help IP select foods to supplement their rations.
IP expend much more energy during isolating situations (especially while evading or traveling) than they would in the course of their normal everyday jobs and life. Basal metabolism is the amount of energy expended by the body when it is in a resting state. The rate of basal metabolism will vary slightly with regard to the sex, age, weight, height, and race of a person. The basic energy expended or number of calories consumed by the hour will change as a person’s activity level changes. For example, a person who is simply sitting in a warm shelter, may consume anywhere from 20 to 100 calories per hour, while that same person in evasion situation maneuvering through thick undergrowth with a heavy pack, would expand a greater amount of energy. In an isolating event, proper food can make the difference between success and failure.
Carbohydrates, Fats, and Proteins
The three major categories of food are carbohydrates, fats, and proteins. Vitamins and minerals are also important as they keep certain essential body processes in good working order. It is also necessary for an IP to maintain proper water and salt levels in their bodies, as they aid in the body’s ability to break down and use food, as well as preventing certain heat and cold disorders.
Carbohydrates are composed of very simple molecules which are easily digested. Carbohydrates lose little of their energy to the process of digestion and are therefore efficient energy suppliers. Because carbohydrates supply easily used energy, many nutritionists recommend that, if possible, individuals should try to use them for up to half of their calorie intake. Obviously, since an IP in an isolating event is likely to expend more than the individual faced with a normal day, they should increase their intact of carbohydrates to 60-70 percent of their total calories from carbohydrates. It is important that IPs, if possible, eat before, during, and after the isolating event to make sure that they will have enough energy in the muscles for the next obstacle or task they must overcome or accomplish. Examples of carbohydrates include: starches, sugars, and cellulose. These can be found in fruits, vegetables, candy, milk, cereals, legumes, and baked goods. Cellulose cannot be digested by humans, but it does provide needed roughage for the diet.
Fats are more complex than carbohydrates. The energy contained in fats is released slower than the energy in carbohydrates. As a result, it is a longer lasting form of energy. Fats supply certain fat-soluble vitamins. Sources of these fats and vitamins include butter, cheese, oils, nuts, egg yolks, margarine, and animal fats. If IP eat fats before sleeping, they will be warmer during sleep. If fats aren’t included in the diet of IP, they can become run down and irritable. This can lead to both physical and psychological breakdown.
The digestive process breaks protein down into various amino acids. These amino acids are formed into new body tissue protein, such as muscles. Some protein gives the body the exact amino acids required to rebuild itself. These proteins are referred to as “complete.” Protein that lacks one or more of these essential amino acids is referred to as “incomplete.” Incomplete protein examples include cheese, milk, cereal grains, and legumes. Incomplete protein when eaten in combination with milk and beans for example, can supply an assortment of amino acids needed by the body. Some complete protein is found in fish, meat, poultry, and blood. No matter which type of protein is consumed, it will contain the most complex molecules of any food type listed.
If possible, a recommended daily allowance of two and a half to three ounces complete protein should be consumed by each IP each day. If only incomplete protein is available, two, three, or even four types of foods may need to be eaten in combination so enough amino acids are combined to form complete protein.
If amino acids are introduced into the body in a large amount and some of them are not used for the rebuilding of muscle, they are changed into fuel or stored in the body as fat. Because protein contains the more complex molecules, over fats and carbohydrates, protein supplies energy after other forms of energy have been used up. A lack of protein causes malnutrition, skin and hair disorders, as well as muscle atrophy.
Vitamins occur in small quantities in many foods, and are essential for normal growth and health. Their chief function is to regulate the body processes. Vitamins can generally be placed into two groups: fat-soluble and water-soluble. The body only stores slight amounts of the water-soluble type. During a long isolating event where a routinely balanced diet is not available, IP must overcome food aversions and eat as much of a variety of vitamin-rich foods as possible. Often one or more of the four basic food groups (meat, fish, poultry, vegetables and fruits, grain and cereal, milk and milk products) are not available in the form of familiar foods, and vitamin deficiencies such as beriberi or scurvy result. If IP can overcome aversions to local foods high in vitamins, these diseases as well as signs and symptoms such as depression and irritability can be warded off.
Adequate minerals can also be provided by a balanced diet. Minerals build and (or) repair the skeletal system and regulate normal body functions. Minerals needed by the body include iodine, calcium, iron, and salt. A lack of minerals can cause problems with muscle coordination, nerves, water retention, and the ability to form or maintain healthy red blood cells.
For IP to maintain their efficiency due to the extremes of an isolating event and work involved, the following number of calories per day is recommended. These figures will vary because of individual differences in basal metabolism, weight, etc. During warm weather, IP should consume anywhere from 3,000 to 5,000 calories per day. In cold weather, the calorie intake should rise from 4,000 to 6,000 calories per day. A familiarity with the calorie and fat amounts in foods is important for IP to meet their nutritional needs. For example, it would take quite a few mussels and dandelion greens to meet those requirements. IP should attempt to be familiar enough with foods that they can select or find foods that provide a high calorie intake.