Food is any substance consisting essentially of protein, carbohydrates, fats, minerals, vitamins, and water that is used in the body to sustain growth, to build and repair tissues, to furnish energy, and to sustain the vital processes of the body. The body's needs for the various nutrients vary with age, sex, occupation, and environment. A child needs certain foods to grow and the body continues to require certain foods for its upkeep. Vitamins, minerals, and proteins provide regulators that enable the body to use other materials. Fuel for the body's energy and warmth is provided by food.

Calories

A knowledge of the calorie content of food is important to you as an MS. Your skill in developing healthy menus plays a critical role in the support of the physical fitness and personal appearance of Navy personnel. The role of the foodservice division in meeting this need is providing lower calorie food choices. Some low-calorie food choices include low-calorie salad dressing; salads and relishes (raw vegetables); skim and/or low-fat milk; fresh and/or tamed fruit drained of syrup; lean meat, poultry, fish, or seafood without added high-calorie sauces or gravies; a vegetable choice without added fat; and light desserts in smaller portions. Think-thin menus are planned using the same principles and standards used for the general menu and should be based on the general menu. Think-thin menus should include all the basic menu components while eliminating high-calorie extras such as gravies, sauces, and toppings. Calorie content is influenced by preparation methods and portion size. Guidance on planning low-calorie meals, low-fat food preparation, and think-thin portion sizes of Armed Forces Recipe Service (AFRS) recipes is contained in Foodservice Operations, NAVSUP P421.

Food Nutrients

There are six types of food nutrients. Most of us can get enough of these nutrients by eating foods from the major food groups each day. These nutrients are discussed next.

PROTEINS.-The chief function of protein in the body is to supply the tissue-building material. Protein itself is a chemically complex organic substance that contains nitrogen in combination with carbon, oxygen, and hydrogen. In the process of digestion, these substances break down into smaller units called amino acids. These units, in turn, are rebuilt into body protein. Certain amino acids are necessary for maintaining growth, weight, and good health. Foods are classified as protein foods only when they contain protein in sufficient amounts to be of value when the food is consumed in normal amounts.

Animal protein foods-meat, poultry, fish, eggs, milk, and milk products, such as cheese-contain the necessary amino acids essential to body structure. The protein in cereals, vegetables, and legumes lacks some of the important amino acids and alone cannot support growth. However, vegetable proteins such as dried beans, dried peas, and peanuts can supplement the animal proteins, and when they are served in the proper combination can provide all the essential amino acids without the addition of any animal protein.

FATS.- Fats provide twice as much energy and calories as do carbohydrates or protein. Fats are important in the diet to furnish energy, provide essential fatty acids, transport fat-soluble vitamins and aid in their absorption, increase palatability, and give a feeling of fullness. However, it is becoming increasingly clear that excessive amounts of total fat may lead to an increased risk of coronary heart and vascular diseases. Emphasis should be placed on planning menus toward attainment of lower fat concentrations while maintaining acceptability. A significant reduction of fat can be achieved by lowering added fats during food preparation and increasing the proportion of lean meats, fish, poultry, skim milk, and other low-fat dairy products in the menu.

CARBOHYDRATES.- Carbohydrates are generally low in calories and fat and high in fiber. Complex carbohydrates are found in grains, vegetables, and legumes such as dried beans and split peas. Nutritionists recommend that we get at least 55- to 60-percent of our calories from complex carbohydrates. Complex carbohydrate foods play an important role in weight control. They supply the body with energy in a constant, time-released manner. Since carbohydrates supply sustained energy, athletes should get 60- to 70-percent of their calories from carbohydrates. Carbohydrates are stored in the muscles as glycogen, which is essential for endurance. Additionally, a diet high in the soluble fiber found in legumes, fruits, vegetables, and some grains may play a role in lowering blood cholesterol.

MINERALS.- Twenty known minerals are essential to health. Some of the more important minerals will be explained next.

Calcium.- The most abundant mineral in the body is calcium and, except for iron, it is the most Likely to be inadequate in the diets of many age groups. (From the age of 9, the diets of many girls and women may lack as much as 25 percent to 30 percent of the calcium they need.) Almost all calcium, and most phosphorus, which works closely with calcium in the body, is in the bones and teeth.

The rest plays a vital role in tissue and body fluids. Soft tissue, or muscle, also has a high phosphorus content. Calcium is required for blood to clot and for the heart to function normally. The nervous system does not work properly when calcium levels in the blood are below normal.

In the United States we rely on milk as a basic source of calcium, and 2 cups of milk, or an equivalent amount of cheese or other dairy products except butter, go a long way toward supplying all the calcium needed for the day.

But milk is not the only source. Dark green leafy vegetables, such as collards, mustard greens, or turnip greens, provide some calcium, and salmon and sardines supply useful amounts of it if the very tiny bones are eaten.

Phosphorus.- Phosphorus is necessary for building bones and teeth. Milk, cheese, eggs, meat, legumes, nuts, whole grain cereals, and vegetables are good sources of this mineral.

Iron.- Iron carries oxygen in the blood. The best sources of iron are meats (especially liver). But foods from some plants, such as dried beans, dark green leafy vegetables, and grains, are good sources of iron, especially when eaten along with foods rich in vitamin C. Vitamin C helps the body absorb iron better.

Iodine.- The most important fact about iodine is that a deficiency of it can cause a goiter-a swelling of the thyroid gland.  Important sources are seafoods, plants grown in the soil near the sea, and iodized salt, which is used in all Navy messes.

Salt.- Salt is needed by everyone. A person needs about 1 level teaspoon of salt per day and more when a person perspires a great deal. The average intake of salt is from 2 to 3 teaspoons daily, which is enough for a person drinking up to about 4 quarts of water. A person who is not getting enough salt will become weak.

Many Americans eat more salt and sodium than we need. Salt contains sodium and is already present in many canned or processed foods. Excess salt contributes to high blood pressure in some people.

Sodium (salt) has been reduced in AFRS recipes to minimum acceptable levels. Sodium can be further reduced in recipes by using the following guidelines:

Season food with herbs and spices instead of high-sodium items like salt, soy sauce, or steak sauce.

Choose fresh rather than canned food items. Look for prepared foods that say low or reduced sodium on the label.

VITAMINS.- There are about 13 vitamins that are absolutely necessary for good health. Four are called fat-soluble vitamins because they dissolve in fat. These are vitamins A, D, E, and K. They are digested and absorbed with the help of fats from the diet. These vitamins can be stored in the body for long periods of time, mostly in fatty tissue and in the liver.

Nine other vitamins are called water soluble. They include eight B vitamins and vitamin C. These vitamins are not stored in the body very long, so you need to eat foods that are good sources of these vitamins every day.

A few of these vitamins are of great importance and you should know what foods provide them.

Vitamin A.- This vitamin plays a very important role in eye function and in keeping the skin and mucous membranes resistant to infection. Although vitamin A occurs only in foods of animal origin, the deep yellow and dark green vegetables and fruits supply a material-carotene-that your body can turn into vitamin A.

Vitamin A is found in yellow, orange, and green vegetables; yellow fruits; and in the fat of animal products like fish, milk, eggs, and liver. Both cheese made from whole milk, and margarine enriched with vitamin A supply this vitamin.

Vitamin C.- Vitamin C, ascorbic acid, is not completely understood, but it is considered important in helping to maintain the cementing material that holds body cells together. Vitamin C is needed for wound healing; for development of blood vessels, bones, teeth, and other tissues; and for minerals to be used by the body.

Vitamin C is found in citrus fruits, melons, berries, leafy green vegetables, broccoli, raw cabbage, spinach, and turnip and collard greens. Potatoes and sweet potatoes provide helpful amounts of vitamin C and so do tomatoes and peppers.

Vitamin D.- Vitamin D is readily available in fortified milk. Sunlight enables the body to produce this vitamin if it has a chance to shine directly on the skin. Vitamin D is needed for using calcium and phosphorus to build strong bones and teeth. Vitamin D is added to most milk. It is also found in fatty fish, liver, eggs, and butter.

Vitamin E.- Vitamin E helps preserve the cell tissues. Although vitamin E's exact role in the body is not fully understood, it is being explored as an antioxidant that may retard some aspects of the aging process. Vitamin E is found in a wide variety of foods, and most people get enough. Vegetable oils and whole grain cereals are particularly rich sources.

Vitamin K.- Vitamin K is essential because it indirectly helps blood to clot. Vitamin K is widely distributed in a variety of foods such as the green and leafy vegetables, tomatoes, cauliflower, egg yolks, soybean oil, and any kind of liver. It is also manufactured in the body.

Three of the best known B vitamins-riboflavin, thiamine, and niacin-release the energy in food. They also have a role in the nervous system, keep the digestive system working calmly, and help maintain a healthy skin.

Thiamine (B1).- Thiamine is abundant in only a few foods. Lean pork is one. Dry beans and peas, some of the organ meats, and some nuts supply some thiamine.

A lack of thiamine (vitamin B ) causes beriberi. Fortunately, this disease is now almost nonexistent in the United States, although it is still seen in some alcoholics.

Riboflavin (B2).- Riboflavin is easy to find and extremely important in the diet. It is plentifully supplied by meats, milk and whole grain or enriched breads and cereals. Organ meats (liver, kidney, and so on) also supply this vitamin.

Niacin.-Niacin (nicotinic acid) prevents a disease called pellagra. It aids in digestion and the health of the skin.

Whole grain and enriched cereals and bread are dependable sources of niacin. Niacin also can be found in meat and meat products and peas and beans.

Other B Vitamins.- Other B vitamins, such as B6, B 12, and folacin, are needed to maintain normal hemoglobin-the substance in blood that carries oxygen to the tissues. Vitamin B,, occurs in foods of animal origin. Folacin helps in the production of red blood cells and is available in many foods but in small quantities. Sources of folacin are liver, green vegetables, whole grains, and dry beans.

Strict vegetarians run a risk of developing the symptoms of B12 deficiency; these include soreness of the mouth and tongue, numbness and tingling in the hands and legs, anemia and loss of coordination.

WATER.- Water is often called the forgotten nutrient. It is needed to replace lost body water, Water helps transport nutrients, remove waste, and regulate body temperature.

CONSERVING NUTRIENTS.-It is not enough just to select the proper foods for the menu. They must be prepared in such a way that valuable nutrients are not lost. T  1  -1 presents summary information about vitamins.  In addition to listing foods that are good sources of vitamins, it also shows conditions under which the vitamin content may be reduced and the effect of their deficiency in the diet. This information will be valuable to you in making and analyzing menus, and also in conserving vitamins during cooking. The term stability used in the illustration refers to the ability of the various substances to withstand destruction under the conditions mentioned.

The following cooking rules, if followed, will make your meals more nutritious and add to the general health of the crew.

Serve fresh fruits and vegetables as soon after you receive them as possible.

Handle fresh fruits and vegetables carefully because bruising causes a rapid loss of vitamins.

Store fresh fruits and vegetables properly until they are to be used.

Do not soak vegetables in water longer than necessary to freshen or clean them. Water will dissolve vitamins B1, B2, C, and minerals.

To cook vegetables, place them in rapidly boiling water. Bring the water back to a boil and reduce to a simmer.

Cook vegetables quickly and just until tender in order to leave them with some of their original crispness.

Cook vegetables in as little water as possible.

Do not throw away cooking water. Save it for use in soups, sauces, and gravies.

Heat canned vegetables quickly just before serving.

Shred outer leaves of lettuce, cabbage, and green leaves of celery for use in flavoring soups.

Serve fruits and vegetables raw in salads.

Table 7-1.-Summary Information on Vitamins

Prepare fruits and vegetables for salads just before serving.

When salmon salad is prepared, save the juice and use it in salad dressing or as a part of the liquid for salmon loaf or sauce.

Prepare hot foods just in time to be served. Never prepare them early and reheat them.

The foods that we eat each day must supply the proteins, carbohydrates, fats, minerals, and vitamins that are needed to maintain the body in a healthy condition. Most foods centain more than one nutrient, but no single food provides all the nutrients in proper quantities. Therefore, it is necessary for the diet to include a variety of foods, and this is accomplished through well-planned menus.

Menu planners should judge the nutritional adequacy of their menus and special rations. Detailed analysis of nutrients is not required if the menu includes a wide variety of foods and the food guide pyramid for daily food choices is used. This pyramid provides a simple, quick, and reliable method of judging the menu's nutritional adequacy. The guide divides commonly eaten foods into five major food groups according to the nutritional contributions they make.