Everyone knows that smoking is a gross and unhealthy habit, yet millions of people around the world still do it.

While most people know that smoking can cause a number of health problems, there are many other reasons you should stop smoking as well. Here are three of them.

Alzheimer’s Disease
Did you know that people who smoke will suffer a rate of mental decline that is up to five times faster than that of a nonsmoker? Alzheimer’s disease is a scary and serious disease and smoking can make it worse. If you want to be mentally fit and healthy as you grow old, knock that smoking habit now, before it’s too late.

This is a wake up call, smoking destroys the male Y chromosome. @nbc http://t.co/0VqiuQDked pic.twitter.com/yzCRoeJRJl

— Nebraska Blue (@BCBSNebraska) December 7, 2014

Autoimmune Disease
Smoking has been linked to a number of autoimmune disorders and diseases, including Lupus and arthritis. Lupus is a chronic inflammatory disease that causes pain and discomfort in the joints and throughout the body. A Harvard study recently found that people who smoke are more likely to develop Lupus and to experience more severe symptoms than non-smokers.

Self-help Tips to quit Smoking http://t.co/ouYzyNV3iK #Pakistan pic.twitter.com/MKEoLh4yGl

— BreakingNewsPakistan (@BreakingNewPak) December 6, 2014

Sexual Dysfunction
If you want to perform well in the bedroom, you should stop smoking now. A study conducted in China shows that men who smoke are 60% more likely to suffer from impotence than men who do not smoke. Women who smoke can experience a decreased sex drive.

If you really need a better reason to quit smoking than avoiding cancer, consider the three reasons above. Nothing good can come from smoking, so why are you still doing it?