A therapeutic diet is a meal plan that controls the intake of certain foods. It’s a practice followed in many hospitals as part of the treatment of a medical condition and are normally prescribed by a physician and planned by a dietician. A therapeutic diet is usually a modification of a regular diet. Diets are modified for consistency, nutrition and new methods of making regular dishes.
The normal diet may be modified:
- to provide a change in the constituents of the diet.
- to maintain, restore or correct nutritional status
- to include all nutrients in the diet
- to increase or decrease the energy value of the diet
- to provide foods bland in flavour.
- to modify the intervals of feeding.
1.1 MODIFICATION IN CONSISTENCY
These diets are used in the treatment of gastro intestinal tract. These diets can range from a very low residue diet to a very high fibre diet. Method of feeding is oral.
a. DIETS WITHOUT SOLIDS
(i) Liquid Diets
Liquid diets consist of foods that are liquid at room temperature and are used in:
- Febrile states (acute fever)
- Post operative conditions
b. DIETS WITH SOLIDS
(i) Soft and Low Fibre Diets
Soft diet is between liquid diet and normal diet. Soft diet includes both liquid and solid foods which contain restricted amount of indigestible carbohydrates and no tough connective tissue. The diet can be made soft by cooking, mashing, pureeing the foods used in a diet under normal conditions. One could also use of refined breads, cereals, vegetables and fruits. This diet is soft in texture and bland to taste.
(ii) Low Residue Diets
The diet is made up of foods which can be completely absorbed, leaving little or no residue for faeces formation. This diet is low in its mineral and vitamin content. Such diets need to be supplemented and foods high in fibre should be omitted. Two cups of milk may be permitted on a daily basis. Fruits and vegetables without skins are allowed. Meat should be tender or ground to reduce connective tissue. The diet is usually used in severe diarrhoea, acute diverticulitis, post operations etc.
(iii) High Fibre Diets
Dietary fibre plays a significant role in colonic function. A high-fiber diet includes foods that have a high fiber content. Fiber is essentially the outer crust of fruits, vegetables, and grains that is not broken down by the body. It helps in excretion of body wastes. Its also well known that fiber regulates the cholesterol levels. Oats, beans, peas, and certain fruits and vegetables (oranges, pears, brussels sprouts, and carrots) are rich sources of fiber. Recommended in case of constipation, or high cholesterol. This is a normal diet with fibre increased to 15–20 gms daily.
1.2 MODIFICATION IN NUTRIENTS
Modification or change in the nutrient composition of the diet to increase or decrease the availability of nutrients to suit the body requirements / limitations of a person.
a. High Calorie Diets
This is a normal diet with an increase in the calorie level to 3000 or more. If appetite is poor, small servings of highly reinforced foods are given. The diet may be modified in consistency and flavour, according to specific needs. Excessive amounts of foods that have a low calorific value and fried foods which disturb the appetite should be avoided. These diets are prescribed for
- Weight loss
b. Low Calorie Diet
These diets controls calories, carbohydrates, proteins and fat intake in balanced amount to meet the nutritional needs and control blood sugar and weight. This is a normal diet with energy values reduced to 1500, 1200 or 1000 calories. Protein levels should be at 65 to 100 gms. Supplements of Vitamin A and thiamine are usually required for diets below 1000 calories.
These diets are prescribed for reducing body weight in
- Diabetes Mellitus
- Cardiovascular diseases
- Gall bladder disease
- Preceding surgery.
c. High Protein Diet
These are diets high in plant and animal proteins; used to treat malnutrition or to increase muscle mass. High protein diet of 100 – 125 g per day may be prescribed for a variety of conditions like
- Hyper thyroidism
- After surgery
d. Low Protein Diet
A low-protein diet is a diet in which people reduce their intake of proteins. Such a diet is often prescribed to people with kidney or liver disorders. Low protein diets are usually prescribed for conditions like
- Hepatic encephalopathy
- Acute and chronic glomerulonephrites
- Acute and chronic renal failure
- In-born errors of metabolism.
In severe liver disorders, when protein cannot be synthesized, excess ammonia cannot be converted to urea for excretion and the patient develops hepatic coma. In this situation protein levels must be decreased or completely restricted for a few days. Patients with Kidney require low protein diets since the kidney cannot excrete nitrogenous wastes. Diets containing 18 to 22 gms of high biological value protein may be needed for the chronic uremic patients who is not being dialysed. Low protein diets are also prescribed for patients with in-born errors of metabolism that result from lack of enzymes of the urea cycle.
d. Fat Controlled Diet
Fat controlled diets regulate the amount and type of fat allowed. The total calories from fats should give about 30% and 35% of the total calories with 10% from saturated fat and 12 – 14% from poly-unsaturated fats. Even the intake of cholesterol also is reduced from the average daily intake of 600 to 300 mg. Usually fat controlled diets are prescribed for—
- Gall bladder diseases
- Nontropical sprue
- Celiac disease
- Cystic fibrosis
- Myocardial infarction
- Hyperlipidemisa etc.
e. Low Sodium Diet
The mineral content of the diet may also be modified. Four levels of sodium restriction are used — 250, 500, 1000 and 2400 mgs. The diet excludes excess salty foods and salt in cooking and at the table. This diet is used both to prevent and treat edema. Therefore, it is prescribed for congestive heart failure, hypertension, liver and renal diseases. Then sodium must be added back by means of the diet.