It is entirely correct that some people sleep less than others. There is wide variation in the amount of sleep that individual people need, and I would not worry
to much if you have always been a bit of a short sleeper.
There are numerous studies looking at the effects of length of sleep on health. Interestingly, while it is true that not sleeping enough can have bad effects on your health, it is also true that sleeping too much can have similar effects. However, most people do know when they are are not sleeping the proper amount of time, because they start to have symptoms of fatigue.
The main thing is to listen to your own body. As long as you are not feeling fatigued and that you have the energy to do the things you need to get done, then you are probably sleeping the right amount of time. Of course, it is also important to maintain a healthy lifestyle in other ways - cutting down on stress, eating regular, nutritious meals, and exercising daily.
As always, talk to your primary care doctor
for more specific information about your own sleep patterns.