The stack is all natural ingredients which elevates your body's ability to release a higher than usual level of testosterone, so shut-down is not even in the same galaxy as this supplement.
It is not exogenous (put INTO the body from outside by means of swallowing on injecting), synthetic variants of the male hormone testosterone, so your HPTA will not be affected. You will be stronger, recover faster, have a higher sex drive EVEN if you are only 20 now. This is one of the products I would advise at your age. make sure your training, diet and resting is all in check and you'll love it.