I understand why entropy tends to a maximum; it is the tendency of a system to spend most of its time in the macroscopic state that corresponds to the largest number of phase cell configurations. How does entropy increase with age in humans?
The law states that entropy increases in isolated systems.
Let us take a cell, as an example of a live organism.
If you isolate a cell, it will die, and the entropy of the isolated system will increase , as an isolated cell cannot live.
All organisms live by continuously decreasing their own entropy and increasing the entropy of the surroundings, considering the earth as the isolated system.
It is simpler to contemplate a crystal coming out of a solution. The crystal forms by decreasing the entropy its equivalent mass has in the liquid but the whole system can be isolated and the entropy increases overall.