Smoking kills, but maybe it heals, too. Nicotine, that addictive drug in cigarettes, protects from Parkinson's disease, found a study in the Journal of the Federation of American Societies for Experimental Biology. Okay, so smoking, per-se doesn't provide any health benefits, but if you feel guilty about your smoking habit (or even if you don't), you can tell yourself you're not ruining every part of your body as you inhale--your brain appreciates it!

Using mice as test subjects, researchers found that nicotine had the potential to rescue dopamine neurons in cultures. Slowly losing these neurons is a hallmark of Parkinson's, so scientists believe this shows that nicotine can be used to treat Parkinsons by targeting the brain's nicotine receptors. Smokers: at least you have that going for you.

But you also have something else to cheer about--this isn't the first positive link found between nicotine and health. Earlier research from the Center for Neurogenomics and Cognitive Research has shown that nicotine enhances learning and memory. Stimulating the brain's nicotine receptors could also help treat Alzheimers, a study from the University of Maryland discovered. The drug can also reduce depression, found a study in the Journal of Pharmacology. Nicotine stimulates the release of serotonin and dopamine, which are strongly inversely associated with depression. The study also found that smokers may be more prone to depression than non-smokers. "People with depression may be self-medicating by smoking, albeit in a deadly way," researcher Dr. Joseph McClernon added.

Nicotine could have some positive effect not just on the brain but on the heart. The drug boosts growth of blood vessels, which could lead to developments in diabetes treatment, a Stanford study found.

But no matter the benefits research has found for nicotine, researcher at the Journal of the Federation of American Societies for Experimental Biology Gerald Weissmann reminds smokers of the downside to lighting up. "Even if smoking protects you from Parkinson's, you might not live long enough to develop the disease because smoking greatly increases the risk for deadly cancers and cardiovascular diseases." So we wouldn't suggest picking up a pack-a-day habit to medicate any potential brain issues.