biochemistry

1. BASIC METABOLIC
RATE

2. CONTENTS
 INTRODUCTION
 DEFINATION
 MEASURMENT OF BMR
 NORMAL VALUES OF BMR
 FACTOR AFFECTING BMR
 SIGNIFICANCE

3. INTRODUCTION
 Food is the fuel source of the body , the ingested food undergoes
metabolism to liberate energy requires for the vital activities of the body.
 Man consumes energy to meet the fuel demands of the three ongoing
processes in the body:
 Basal metabolic rate
 Specific dynamic action
 Physical activity

4. Basal Metabolic Rate
 BMR- minimum amount of energy required by the body to maintain life
at complete physical and mental rest in post absorptive state.
 Several function with in the body occur at basal condition:
 Working of heart and other organs.
 Conduction of nerve impulse.
 Reabsorption of renal tubules.
 GIT motility.
 Ion transport across membranes.

5. Measurement of BMR
 BMR can be measured by the apparatus of benedicts and roth or by
douglas bag method.
 The subject should be awake , at compl;ete physical and mental rest , in
post absorptive state and in a comfortable state.

6. NORMAL VALUES OF BMR
In adults man the BMR value is about 1600 calories per day.
In adult women the BMR value is about 1400 calories per day.
A BMR Value between -15% and +20% is considered normal.

7. Factors affecting BMR
 Surface area is directly proportional to the BMR.
 Men have marginally high BMR then women.
 BMR increase with regular exercise .
 Thyroid hormones , epinephrine , cortisol, sex hormone and growth
hormone increase BMR.
 BMR increase in cold climates compared to warm climates.
 During starvation a decrease in BMR upto 50% has been reported.
 Fever increase BMR 10% increase for every 1C rise in body tempreture.

8. Significance of BMR
 BMR is important to calculate the caloric requirement of an individual and
planning of diets .
 Assessment of thyroid function.
 BMR is below normal in starvation under nutrition and addisons disease.
 BMR is above normal in fever , diabetes insipidus , leukemia and
polycythemia.