Is there any good in nicotine?

Nicotine, which is commonly found in cigarettes are bad for your health. Excessive smoking can lead to various illnesses and can cause death. Once you have tried smoking, it would be hard for you to stop because of the nicotine's highly addictive effect.
Surprisingly, reports show that nicotine possesses a positive effect to the human body, if used properly. Nicotine acts as an enhancer for cognitive functioning, attention booster, and an untapped potential for working memory and nicotine is also giving light in the protection against Alzheimer's disease.
Aside from those, nicotine also helps in protecting Parkinson's disease, weight loss, Tourette's disease, ulcerative colitis, and sleep apnea with of course, habitual consumption. Apparently, nicotine is also an antidepressant. It showed great effect in lifting someone's mood and helping them slowly feel the absence of feeling depressed.

If nicotine provides such effects, why is smoking harmful?

Obviously, nicotine is not the only ingredient of a cigarette. Nicotine has been misjudged and has become the cause of most illnesses of smokers, especially cancer. No. Nicotine does not contribute to the cancer caused by excessive smoking because nicotine is not a carcinogen, as noted by US Centers for Disease Control or CDC.

What are other ways of getting nicotine without smoking?

If you happen to watch Sherlock Holmes which was starred by Benedict Cumberbatch, there are scenes that he uses nicotine patches to help him in his thinking and focus. These patches are also a very good substitute for the cigarettes because nicotine patches does not contribute with the mixing of nicotine to your bloodstream. It gives the effect through the skin.
Aside from nicotine patches, vape is also a good substitute instead of smoking cigarettes. However, the delivery of nicotine by using vape may not be as fast as smoking, but the latter is never safe when used repeatedly.

Are the benefits of nicotine for the smokers only?

It will be easy for a smoker to switch from cigarettes to a nicotine patch or a vape. However, it is not the case for non-smokers. The latter have difficulties in differentiating nicotine and smoking because non-smokers tend to associate the two.
So if a non-smoker is open to the idea of having nicotine for health benefits, then one should aware of nicotine's ups and downs, most importantly, a consult from the expert would be best.

Conclusion
Nicotine is always getting the wrong impression because of it being a well known component of a cigarette or tobacco. Nicotine is just being mixed with the other harmful chemicals like carcinogens that make it harmful when someone smokes. In comparison to a saying, "it just belonged to the wrong group".
However, no matter how interesting nicotine's benefit for the human body, the bad side is never to be forgotten. These benefits have been discovered quite a long time ago but developments regarding these and how to get these benefits without sacrificing the health of the user does not seem to be progressive.
So if one wants to badly enjoy the benefits of nicotine, the choices are nicotine patch, vaping, or smoking. But lastly, keep in mind to do research and ask experts before making a move.