Niagen may be the fountain of youth for so many, with the component Nicotinamide Riboside that helps improve communication within the cells and cut down on age by 66 percent. A direct result of this is anti aging effect.
However that is not all that Niagen/ Nicotinamide Riboside can do for users. It is not just the wrinkles that disappear, the effects go way deeper. Other than strengthening mitochondrial activity it also helps with cognitive function and acts as a shield against neurological diseases.
To understand all the benefits and side effects of the drug Niagen you need to understand where this drug comes from. According to the official website of Niagen, Nicotinamide Riboside was discovered to have anti aging properties in 2013 by Dr. David Sinclair of Harvard Medical. His clinical study was performed on mice. At the end of the study Nicotinamide Riboside had the tissue resembling that of 6 month old mice. In human years that would be a 60 year old being transformed into a 20 year old. 
One of the reasons that Niagen is considered a big deal in the medical world is because some of its effects target the deadly diseases, especially the ones present in the brain.
Niagen performs as an extra safeguard against axonal degeneration, by first supporting and maintaining cellular health in the brain.
Other than this improved memory, better sleep, hearing, and vision are just some of the other positive effects. Currently Niagen supplements are being tested for college football players against concussions.
Some of the most exciting thing to come out of clinical research on Nicotinamide Riboside is that it prevents the effects of tumors and cancers. A study conducted in November 2014 revealed how the restoration of NAD+ pools through the component Nicotinamide Riboside prevent DNA damage and tumor formation. 
The early results are extremely promising. However there is no record of long term results, and proof that these effects will last because the drug has not been out that long.
Do Anti Aging Miracles Have Side Effects Too?
There are hardly any reported side effects from the use of Niagen. If you research online, you won’t find any listed on their website or independent forums either. What you will find is some people claiming that the drug does not seem to be similar to VitaPulse. 
All Niagen meds are vegan, gluten and lactose free, and also void of any additives. The core ingredient of Niagen, which is Nicotinamide Riboside is a natural nutrient present in beer, and milk. The component is safe to use and causes no unpleasant side effects.
All that being said, Niagen is a relatively new supplement with plenty of ongoing researches. If you are trying out this new med, it makes sense that you keep yourself informed all ongoing relevant research regarding it.