advantages of biochemical method
1. it is useful in detecting early changes in body metabolism&nutrition before the appearance of overt clinical signs.
2.it is precise,accurate and reproducible.
3. useful to validate data obtained from dietary method e.g. comparing salt intake with 24-hour urinary excretion.
limitations of biochemical method
1.time consuming
2. expensive
3. they cannot be applied on large scale
4.need trained personnel&facilities