How can one have an imbalance in a substance, but not actually have elevated or deficient levels of that substance in the body?

How can one have an imbalance in a substance, but not actually have elevated or deficient levels of that substance in the body? Without having an absolute excess or deficiency of a substance, one can have too much or too little of that substance in a given compartment. Such a relative increase or decrease is due to a redistribution of water or the ion in the body’s compartments.

Explanation:

which

what is a measurement of the earth’s history divided into time periods?

> fossil record <

sedimentary rock

> geologic time scale <

radioactive elements