Ask yourself this important question: Why are you interested in going to the AN Beach? If your answers are personal, such as, you want an all-over tan, no restricting suits and straps, you want to enjoy swimming naked or you want to expand your relationship and experiences with your partner, then you are doing it for the right reasons. If your reasons are to "see" what goes on there, check out other people or want other people to check you out, then stay at the other beach. You can do all of that there.
Age and physical appearance DOES NOT MATTER. Mature "nudies" don't care about impressing others physically. The beauty of being a nudist is shedding all the superficial means which people use to hide behind or impress. At the AN Beach you meet and get to know people who are completely confident with themselves, non-judgemental, respectful and mature.
So, if you are considering exploring the AN Beach for the first time in Negril, do some internal exploring first. Be mature about it because you will be called out. Just like the "gawkers" are.