Does rejuvacore-NT really work

I have been using it for 3 months and like it. When I first started taking it I noticed a big difference in my energy level but that seems to have leveled off or I have just gotten used to it. I am 50 years old and I have taken vitamins all my life. I thought I would try something new and have stopped taking vitamins and only take this. I just ordered another 3 month supply so I must be sold on it.