Diet Prescription

Ordered by MD

Can take many forms

Types of food and amounts

Frequency of meal/eating



Specific nutrient(s)




Short vs long term

Some diet Rx are short term can should be switched as quickly as possible or tolerated

e.g. clear and full liquid diets may not be nutritionally adequate for long term use

Energy modification

Appetite regulates food intake in people who are healthy

During disease, illness, it is not reliable, so needs must be calculated to accommodate for condition such as hypermetabolic state


Patient may not be active but the metabolism is increased to deal with metabolic stress

e.g. surgery, major accident, sepsis

Calc. of energy need

Kcal/kg/day = BEE + additional energy need + TEF


Harris Benedict equations for males and females

An abbreviated method:

Males: Kg X 1 Kcal/Kg/hr X 24 hr

Females: Kg X .95 kcal/Kg/hr X 24 hr

Body weight

Desirable body weight is used except in malnourished patients to avoid overfeeding syndrome

Stress factors

Mild 10% of BEE (uncomplicated surgery)

Mod 50% (multiple fracture/trauma)

Severe 100% (burns, infection)


35-40Kcal/kg of desirable body weight

Protein Modification

Healthy adults: RDA of 0.83 g/Kg body weight

Protein requirement increased with growth, malabsorption, burns, exudates, ascites, or renal disease due to increased loss.

E:nitrogen ratio

For patients in hypermetabolic state, E:N ratio is used

100-200Kcal/g N

increased protein requirement = lower ratio


Kg BW X 0.83 g/Kg BW = g protein

Gm protein/6.25 g prot/g N = g N

Kcal/g N = E/N ratio

Fat & CHO

If protein provides 12% of E, then 88% must come from fat and CHO

25 –30% from fat so

58-63 from CHO


60 g protein for RDA and RDA for E = 2000, what is the % of E from protein if based on RDA?

60 g X 4 kcal/g prot = 240 kcal from protein

240 Kcal/2000 Kcal = 12% of total E from protein


For a 60 Kg female, calculate her energy requirement?

E req.

60 kg X 0.95 kcal/kg X 24 hr = 1368 Kcal for REE

activity at 40%: 1368 Kcal X 0.4 = 547 Kcal for activity

TEF: (1368 Kcal + 547 Kcal) X10% = 191.5 kcal

Total = 1368 + 547 + 192 = 2107 kcal

E req

For this 60 Kg female, energy requirement is about 2100 Kcal/day

Prot. Req

60 Kg X0.83 g/Kg = 49.8 g prot. (50 g)

% of energy from protein: 50 g X 4 kcal/g = 200 Kcal

200 kcal/2100kcal = 0.95 (10%)


2100 X 0.25 = 525 Kcal / 9 Kcal/gm = 58.3 g fat


2100 X .65 = 1365 Kcal/4 Kcal/g CHO = 341 gm CHO

Diet Rx:

2100 kcal diet with

10% protein (50 gm protein)

25% fat (48 g fat)

65% CHO (341 gm CHO)

Vit/min content

Start with RDA level

Then adjust for individual need of the patient


Depends on factors:


Stores of nutrients in body/states

Losses due to malabs., burns, kidneys, etc.

Drug interactions

Other potential problems should be assessed


Healthy adults require 1 ml water/Kcal consumed or expended

Fluid adjustments

Excessive sweating/loss




Tube drainage


Watch electrolytes if fluids are being replaced parenterally (iv)

Therapeutic diets

Normal diets can be used and adjusted depending on patients’ needs

Diets can be adjusted for qualitatively or quantitatively

Qualitative diet

Adjustment of type of food e.g. texture and for GI condition

Quantitative diet

Adjust to increase or reduce amount of food constituents e.g. nutrients as in diabetes, renal disease




Type of food

Food omission

Ratio of macronutrients

Freq of meal

Nutrient delivery


Liquid, soft diet, residue or fiber


Increase or reduce depending on wt gain or loss

Type of food

Lactose, sodium, K, content of diet increased or reduced

Food omission

Allergy, intolerances

e.g. celiac disease and gluten

ratio of macronutrients

adjusted for CHO, protein, fat, cholesterol

freq of meal

most people eat 3 meals per day

may increase to 6+ meal depending on tolerance, diabetes, GI

nutrient delivery

feeding methods

per os (mouth)

enteral (tube feeding)

parenteral (IV)

Hospital diets

Important to serve food that are palatable and appealing to the eyes

Standard diets

    1. general/normal diet
    2. soft diet
    3. liquid diet


Aka: normal, full, regular, house diet

1600-2200 Kcal/day

60-80 g protein

80-100 g fat

10-300 g CHO


Uses normal food and nutritionally adequate diet

Menu provides several options

Soft diet

Transition diet, soft food

Low residue/fiber and connective tissues

Does not require chewing

Patients with poor dentition, or GI problems

1800-2000 Kcal/day

Liquid diets

Used for people who can’t chew

Short term use

Full or clear liquid

Full liquid

Can use enteral formula

1300-1500 kcal/day with 45 gm protein, 65 g fat, 150 g CHO

clear liq.

Jello, sugar sweetened fluids, no dairy products, no juices with pulps

Used for post-op patients to provide fluids, electrolytes, and energy

Inadequate for long term use

400-500 Kcal/day with 5-10 g prot., no fat, 100-120 g CHO not much vit/minerals

Food intake

Analyze what is actually eaten by patient

Meal time

Pschological factors to be considered

+ meal time environment, familiar foods, if possible, let patient eat by him/herself, respect eating schedule, tempt of food, allow pt to choose from menu, explain dietary justification, health care team must support each other and no complaints or critical comments in front of patient.


Planning and home care are important

Pts are going home sicker so need more care later

Explain dietary Rx to pt and caregiver before discharge

F/u a home with home health care team

Include pt in care plan process and care

Terminally ill

Hospice patients need to know rights about life support

Comfort and quality of life issue

Advance directiveness (living wills) be given to relative or family

Palliative care – allows pt to function independently and lives at home while under the care of medical team e.g. hospice care