I usually sleep 8 hours per night, the problem is that I am a reddit junkie and usually go to bed as late as 2:30 a.m. every night.

does it have a negative impact on health? am I predisposing myself to get alzheimer disease?

I can't force myself to change this habit because I do not have a strong enough why I should change it. I do not feel sleepy in the morning, but nontheless I am concerned.