A cultivator's body was similar to that of a person who did not cultivate. Although these experts considered the ones who could not cultivate, or at least reach a certain level, as mortals, the fact was that none of them were immortals.
The Qi, which roamed their bodies, was capable of strengthening their cells, making it much more unlikely for them to become sick, and at the same time also increasing their lifespan, but they would still eventually die of old age if they did not reach the true ranks of immortals.
Unfortunately, this continent was a place with very thin heaven and earth essence, which made it so that their chances of reaching this level was extremely low.