We have had success with folks of all ages and sizes. The Puerto Rican Navy can be seen loading and off loading individuals of all sizes and ages. I have witnessed with lots of grandma's or elderly aunts hoisted on and off the boats. If you have the ingress and egress under control you are at least halfway there. No matter the age! The heat and different seated positions can be a challenge for some in less robust health. We have witnessed edema issues in the older, less mobile, and larger. The heat, change in diet, and more seditary that some become on the boat can lead to fluid retention and other health issues. Some may notice sitting on long flights leads to body swelling. If that same person gets on the boat and parks in a comfortable corner edema is not out of the questions. Others get on the boat and have greater activity levels some less. Skip the age. In general how health is the person and what known health issues may be exasperated by the days on the boat in the heat? Before you flame me. Consider if you have ever noted a fellow traveler with swollen ankles.