How do you shut down...

[c-Z]

You r body make its natty test.

When the body realizes test is coming from an outside source it stops producing natty test. Your body does this trying to maintain homeostasis.

When you stop use test from an outside source the body will realize there is no source of test anymore and start to produce your natty test again.

You have to hope that the body still produces the correct amount.

Well said chap