Our natures are "saved by pleasures" but "destroyed by pains"
Thinking more correct to say: destroyed by excessive and unnecessary pains.
Important to remember the Letter to Menoeceus says:
"...we pass up many pleasures when we will gain more of what we need from doing so. And we consider many pains to be better than pleasures, if we experience a greater pleasure for a long time from having endured those pains. So every pleasure is a good thing because its nature is favorable to us, yet not every pleasure is to be chosen — just as every pain is a bad thing, yet not every pain is always to be shunned." (...since we are also aiming for health of the body and happiness of the soul).