I'm 42.....but I have not been juicing since 23 years old either. I did my first real cycle only a year ago. My belief is , as in all things....Moderation is the key. To much of almost anything is not good. I feel great while on and like crap when I'm off , but it usually subsides after a month of being off. Then I'm back to normal mentally and emotionally. 2 cycles per year is safe IMO , just making sure I let my body get back to natural test production. I think if I were to stay on a cycle constantly and never let my body produce it's own natural test I would be headed for some long term and possibly permanent damage. JMO
Getting bi monthly blood test and check ups help prevent any trouble , I think that is the key factor here......if you can find a Doctor who will help you rather than ridicule you , you are safer. Just get tested regularly to catch things in the early stages.