## Deriving estimates of energy requirements

Normal and Therapeutic Nutrition 3(2+1)
Lesson 7:Recommended Dietary Allowances (RDA)

Deriving estimates of energy requirements

1. Comparision of energy cost of some common activities in terms of BMR units.

2.  Sitting quietly 1.2 Standing quietly 1.4 Sitting at desk 1.3 Standing & doing lab work 2 Harvesting 3.6 Hand saw 7.4 Typing (sitting) 1.58 Walking (3 MPH) 3.7

Computation of energy requirements of Indian adults in terms of BMR units:

3. Recommended BMR factors for computing energy requirement of Indians

 Recommending Body Sex Sedentary Moderate Heavy ICMR 1989 Man/ Woman 1.6 1.9 2.5 FAO/ WHO/ UNU 1985 Man Woman 1.55 1.56 1.78 1.64 2.10 1.82

 Activity Duration(hr) Sedentary (K.Cal/ Min) Moderate Heavy Sleep 8 1.0 1.0 1.0 Occupational activity 8 1.7 2.8 4.5 Non occupational activity 8 2.2 2.0 Average for (24 hrs) 1.6 1.9 2.5 Computed for 24 hrs Reference Man (60kg) 2424 2882 3788 Reference Woman (50kg) 1872 2223 2925

Energy Requirement of man and woman (K.Cal/ day)

 Sex Body wt(kg) Sedentary Moderate Heavy Man 60 2425 2875 3800 Woman 50 1875 2225 2925

Pregnancy:

During pregnancy additional energy is required for

 Growth of foetus Growth of placenta Total energy cost(55kg woman) is 80,000k cal of this 36,000 k cal is deposited as fat( to be utilized during lactation) Growth of Maternal tissue To meet increased BMR

Additional energy of 5% in first trimester,
12% in second & third trimester
Therefore additional energy allowance of 300 k cal/day during pregnancy is required.

Lactation

Additional energy required during lactation is computed from the volume of milk secreted, its energy content and efficiency of conversion of food energy to milk energy is 80%. Therefore RDA during lactation

0-6 months + 550 k cal/ day
6-12 months + 400 k cal/day

Infants

0-6 months 108k cal/ kg body weight/day
6-12 months 98 k cal/kg body weight/day

RDA for children

Energy needs of children (1- 10 yrs) are computed from energy needs per kg body weight of well- to- do Indian children.

The values of energy requirement of children (k cal/day) for different age groups are given in table.

 AGE GROUP BODY wt(kg) BOYS(k cal/day) GIRLS(k cal/day) 1. 1-3 Yrs 12.2 1240 1240 2. 4-6 Yrs 19.0 1690 1690 3. 7-9 Yrs 26.9 1950 1950 4. 10-12 Yrs 2190 1970 5. 13-15 Yrs 2450 2060 6. 16-18 Yrs 2640 2060