- Caloric Value of Food
Caloric value: Defined as amount of heat produced by burning 1.0 g of food stuff completely in the presence ofO2.
- Caloric value of different food stiffs is determined in vitro in a special apparatus called bomb calorimeter.
- Caloric value of different food stiffs are:
- Carbohydrate = 4.0 cal/gm
- Proteins = 4.0 cal/g
- Fats = 9.0 cal/g
- Alcohol = 7 cal/g
- Basal Metabolic Rate (BMR)
BMR is defined as energy produced by an individual under basal conditions per unit time and per square metre
of body surface. The basal conditions are as follow:
- Person should be awake but at complete rest both physical and mental.
- Person and be without food at least 12 to 18 hrs i.e., in the postabsorptive state.
- Person should be in normal condition of environment i.e., at normal temperature, Pressure & humidity.
- During starvation, BMR is reduced by 50%.
- Respiratory Quotient (RQ)
RQ is the ratio of the value of CO2 produced by a volume of O2 consumed during a given time.
Normal RQ- in a healthy adult, on a mixed diet, it is 0.85
RQ of Different food stuffs
1. RQ for carbohydrate = 1.0
2. RQ for Proteins = 0.8
3. RQ for fats = 0.7