LEARNING OBJECTIVE: Select the appropriate diet for various medical conditions.

It is often necessary to cater to a patient’s appetite, since many individuals become especially hard to please when sick. In some disease states, such as cancer, patients experience marked taste changes. Because of the importance of the nutritional elements in feeding the sick, try to carry out the patient’s wishes whenever possible. A tactful and observant medical technician can be of great benefit to the physician and dietitian in carrying out the dietary regimen. You must be aware of what comprises a well-balanced diet and should be able to recognize when dietary adjustments need to be made in special situations. This is important to meet the changing needs of the diseased body’s ability to make use of foods.

The patient should be made to feel that the utmost cleanliness and care have been observed in the preparation and service of their food. The patient’s face and hands should be cleaned before food is served, and the lips and teeth cleaned before and after the meal. If the mouth is dry, it should be moistened periodically.

When special or modified diets are ordered, check the contents of the tray with the written orders. An error in serving a special diet may cause discomfort, serious illness, or even death.


The objectives of diet therapy are as follows:


Diets used in the treatment of disease are often spoken of by specific names that show a special composition and often indicate the purpose for which the diet is intended.

Regular Diet

The regular diet is composed of all types of foods and is well balanced and capable of maintaining a state of good nutrition. It is intended for convalescing patients who do not require a therapeutic diet.

Modified or Therapeutic Diets

Modified or therapeutic diets are modifications of the regular diet and are designed to meet specific patient needs. These include

SOFT DIET.—The soft diet is soft in texture and consists of liquids and semi-solid foods. It is indicated in certain postoperative cases, for convalescents who cannot tolerate a regular diet, in acute illnesses, and in some gastrointestinal disorders. A soft diet is an intermediate step between a liquid and regular diet and is low in connective tissue and indigestible dietary fiber. Little or no spices are used in its preparation.

The soft diet includes all liquids other than alcohol, and foods that may be incorporated into a soft diet include well-cooked cereals, pastas, white bread and crackers, eggs, cottage cheese, tender meat, fish, poultry, and vegetables (including baked, mashed, and scalloped potatoes). Vegetables can be puréed and meats ground for dental patients. Permitted desserts are custards, gelatin puddings, soft fruits, and simple cakes and cookies. Foods prohibited in a soft diet include fried foods, raw vegetables, and nuts.

LIQUID DIET.—A liquid diet consists of foods that are in a liquid state at body temperature. This type of diet is indicated in some postoperative cases, in acute illnesses, and in inflammatory conditions of the gastrointestinal (GI) tract. It is important that feedings consisting of 6 to 8 ounces or more be given every 2 to 3 hours while the patient is awake.

Liquid diets are usually ordered as clear, full, or dental liquid. A clear liquid diet includes clear broth, black tea or coffee, plain gelatin, and clear fruit juices (apple, grape, and cranberry), popsicles, fruit drinks, and soft drinks. This diet is inadequate in all nutrients. A full liquid diet includes all the liquids served on a clear liquid diet, with the addition of strained cream soups, milk and milk drinks, ice cream, puddings, and custard. The full liquid diet is inadequate in iron, niacin, and possibly Vitamin A and thiamin. A dental liquid diet includes regular foods blended and strained in liquid form and all foods allowed on clear and full liquid diets. Vitamin and mineral supplements may be necessary with the dental liquid diet if the recommended amounts of food are not tolerated.

HIGH-CALORIE DIET.—The high-calorie diet is of a higher caloric value than the average patient normally requires. A high-calorie diet is indicated when an increase of total calories is required by malnourished, underweight, postsurgical, or convalescing patients, especially those recovering from acute illnesses such as infections, burns, and fevers. The increase in calories is obtained by supplementing or modifying the regular diet with high-calorie foods or commercial supplements, by giving larger portions, or by adding snacks. It is given to meet a need for energy caused by the more rapid metabolism that accompanies certain diseases (especially fever, hyperthyroidism, poliomyelitis, and tuberculosis). In the liquid or soft diet, adding fats and carbohydrates increases the caloric value. The high-calorie diet is often ordered along with high protein. Proteins are added to prevent depletion of proteins in the plasma (a condition known as hypoproteinemia). As the patient progresses, a more solid diet is given.

Good sources of high-calorie foods are whole milk, cream, sweets, butter, margarine, fried foods, gravy, sauces, and ice cream. Between-meal feedings consisting of milk, milkshakes, cheese, cookies, or sandwiches are recommended, but these feedings should not interfere with the patient’s appetite at mealtime.

HIGH-PROTEIN DIET.—As previously stated, protein is essential for tissue growth and regeneration. A high-protein diet is indicated in almost all illnesses (e.g., nephrosis, cirrhosis of the liver, infectious hepatitis, burns, radiation injury, fractures, some GI disorders, conditions in which the protein blood level is low, and in preoperative and postoperative cases).

In some acute illnesses and disorders, such as infectious hepatitis, GI disorders, and postoperative conditions, patients may be unable to consume solid foods or the daily requirement of protein and calories because of pain or nausea. In these cases, intravenous fluids with nutrient additives are required for the patient to receive the required amount of protein.

Protein-calorie deficiency is a definite factor in postoperative wound disruption. This disruption can best be prevented by preemptive nutritional measures before surgery. Antibody production will be decreased if the patient receives inadequate protein. Remember, the daily recommended intake of proteins for adults is at least 0.8 g/kg of body weight (approximately 56 g). A high-protein diet should provide a minimum of 1.5 g of protein per kg of body weight (approximately 105 g). The seriously burned and radiation injury patients should receive at least 3.0 g/kg daily.

Supplement the regular diet with high-quality protein foods, such as meat, fish, cheese, milk, and eggs.

LOW-CALORIE DIET.—The low-calorie diet is useful in the treatment of obesity, but it may also be used to control weight in medical conditions such as arthritis, hypertension, diabetes, cardiac disease, or hypothyroidism. A loss of 1to 2 pounds per week is the medically acceptable limit for weight reduction. A low-calorie diet consists of 1,000 to 1,800 calories per day. Calorie levels are determined by physicians and dietitians to help meet specific individual patient weight-loss goals. The daily intake of proteins should be at least 0.8 g/kg of standard body weight. Supplemental vitamins may be ordered if the prescribed diet is less than 1,200 calories.

Patients on low-calorie diets should be instructed by the dietitian (if available) or other medical personnel knowledgeable in proper eating habits. The dietitian conducts patient interviews to learn the patient’s eating behaviors, usual portions, preparation of foods, meal patterns, nutritional adequacy, exercise, and so forth. Individual programs should then be recommended to assist patients to attain and maintain their ideal weight.

The Handbook of Clinical Dietetics, published by the American Dietetic Association, lists the following formula for determining ideal body weight. For females, the basic weight for 5 feet is 100 pounds. Add 5 pounds for every inch over 5 feet. For males, the basic weight for 5 feet is 106 pounds, with 6 pounds added for every inch over 5 feet. Adjustments must be made for body build. Reduce desired weight by 10 percent for a small frame; increase it by 10 percent for a large frame. Total caloric requirements are based on ideal body weight plus activity.

Many patients on low-calorie diets experience hunger. To satisfy this hunger or appetite, low-calorie foods such as raw vegetables, broth, black coffee or tea, and other unsweetened or diet beverages should be provided. Water and sodium need not be restricted unless there are cardiac complications or edema, and the restrictions are ordered by the physician.

LOW-PROTEIN DIET.—As the name implies, the low-protein diet is made up of foods that furnish only small amounts of protein and consist largely of carbohydrates and fats (e.g., foods such as marshmallows, hard candy, and butter). This diet is used in renal diseases associated with nitrogen retention or liver disorders. Limited amounts of protein are sometimes advocated in certain kidney diseases (such as chronic nephrotic edema). Low-protein diets for renal failure are usually restricted in sodium and potassium, because these two elements are not excreted properly during this condition. In some cases of chronic renal insufficiency, the protein content of the diet is varied, usually between 40 and 60 g per day, so that there will be sufficient complete protein to maintain nitrogen equilibrium.

In some metabolic disturbances, such as amino acids in the urine, protein restriction may be of therapeutic value.

HIGH-RESIDUE DIET.—The high-residue (high-bulk, high-fiber, high-roughage) diet is indicated in atonic constipation, spastic colon, irritable bowel syndrome, and diverticulosis. This diet encourages regular elimination by stimulating muscletone, creating softer and larger stools that are more easily propelled through the colon, thereby reducing the pain and cramping that accompany spastic colon or irritable bowel syndrome.

The patient is given a regular diet, with the inclusion of high-residue foods. The main sources of fiber are whole-grain breads and cereals, bran cereals, fresh fruits, and vegetables that are raw or cooked until tender. Whole grain breads and cereals that contain wheat bran have a greater laxative effect than fruits and vegetables, because the bran acts to absorb water within the colon, creating a bulk effect. Fiber intake should be increased gradually to minimize potential side effects of bloating, cramps, and diarrhea. At least one serving of 100 percent wheat bran cereal is recommended daily. Cereals such as raisin bran, Bran Flakes®, Shredded Wheat®, and oatmeal may be used occasionally, but they contain less than halfthe amount of fiber found in All-Bran® or Bran Buds®. Fresh fruits and vegetables with edible skins, such as apples and grapes, are higher in fiber content than canned fruits or vegetables and their juices.

Dietary intake of refined sugars and starches should be decreased because they are poor sources of fiber. Also, limit white flour products, refined cereals, pies, cakes, and cookies.

Too little fluid in the high-residue diet may cause dehydration and lead to constipation. The patient must drink at least eight 8-ounce glasses of water or other fluids daily, particularly when consuming the recommended amount of bran. Drinking too much alcohol, beverages containing caffeine (such as coffee, cola, tea, and soft drinks), however, can irritate a sensitive colon and can cause dehydration. When possible, use decaffeinated coffee. One or two glasses of water in the morning help to stimulate peristalsis. Excessive intake of foods like dried beans, fruits with seeds and skins, nuts, popcorn, and strong spices may cause irritability, especially during the inflammation period of colon disease states. These foods should be individualized to the patient.

When one is progressing from a low-residue diet after an acute infection or diverticulitis, increase fiber in the diet gradually. Start by adding one serving of 100 percent bran cereal and three servings of whole-grain bread to the low-residue menu pattern. Gradually increase the amount of raw vegetables and fresh fruits to at least four servings per day.

LOW-RESIDUE DIET.—The low-residue diet is indicated in ulceration, inflammation, and other gastric disorders (such as partial intestinal obstruction or diverticulitis). It is also used in certain posto­perative states that affect any part of the GI tract, e.g., a hemorrhoidectomy. Low-residue diets are also used in treating dysenteries of long duration.

The purpose of this diet is to provide non-stimulating, non-irritating, and easily digested material that leaves little residue, thus avoiding mechanical irritation of the GI tract. Various commercially prepared low-residue elemental diet supplements may be given to provide complete nutrition.

LOW-SODIUM DIET.—A low-sodium diet consists of foods containing a very small percentage of sodium, with no salt added in preparation or by the patient. It is impossible to prepare an absolutely sodium-free diet.

The low-sodium diet is indicated when edema is present, in renal diseases, hypertension, and certain cardiac conditions.

The nephrotic patient is often unable to excrete sodium in a normal manner because the kidneys’ retention of sodium leads to edema. A low-sodium diet is thus indicated, with no restriction on salt-free liquids. Such patients should be encouraged to drink 2,000 to 3,000 milliliters (ml) of low-sodium fluids daily.

The allowance of sodium in a strict low-sodium diet is 250 to 1,000 mg daily. The allowance of sodium in a moderate low-sodium diet is 2,000 mg or 2 g. Regular diets with no salt added contain 2.4 to 4.5 g of sodium.

Any diet in which the amount of sodium is drastically reduced has possible side effects. The patient who is on this diet regimen must be constantly observed—particularly in warm climates—for lassitude, complaints of weakness, anorexia, nausea and vomiting, mental confusion, abdominal cramps, and aching skeletal muscles. Electrolyte imbalances can have serious consequences. If you observe symptoms such as those described above, notify a medical officer.

BLAND DIET.—A bland diet may be helpful for gastritis, hyperacidity, hemorrhoids, peptic ulcers, and other GI disorders. Dietary management of patients with chronic ulcer disease has been the subject of much controversy. Bland diets have traditionally been used for these patients. However, experiments show that there is no significant difference in the response of patients with an active duodenal ulcer to a bland diet. Known irritants to the gastric mucosa include alcohol, black pepper, caffeine, chili powder, cocoa, coffee, certain drugs, and tea.

Emphasizing how to eat is as important as indicating what foods to eat, since there are individual responses to bland diets. Offer the following suggestions to the patient:

If fruits and juices between meals cause distress, try including them with meals. Meals must be kept small to reduce gastric acidity and distention. Among foods to avoid in the bland diet are

Patients on a bland diet may use spices and condiments such as allspice, cinnamon, mace, paprika, sage, thyme, catsup, cranberry or mint jelly, and extract and flavorings without chocolate or vinegar.

The bland diet allows a more liberal food selection than other restrictive diets. This diet reduces the number of meals to three, and increases the quantity of foods given. Individualize the diet to the patient.

The “Regular-No Stimulants Diet” (also called “liberal bland”), a type of bland diet, eliminates only those items that have been shown scientifically to irritate the gastric mucosa (i.e., alcohol, black pepper, caffeine, chili powder, cocoa, coffee, certain drugs, and tea).

Decaffeinated coffee may be restricted in most types of bland diets. Recent studies show that it causes increased gastric acid secretion and esophageal pressure causing gastric acid reflux in the esophagus. Decaffeinated coffee is only offered on the bland diet