Gonegirl The answer is undoubtedly genes because genes influence things like food preferences, and many other aspects of personality and lifestyle.
I come from healthy long-lived family. My father was one of eleven children. Average life span: 88 years, One still surviving at 92, clear in mind, living independently and still driving locally. Dementia: only 1, he and his wife spent many years in care, but otherwise only one other was in a nursing home for the last few months of pancreatic cancer. Always physically active, generally not prone to gain weight. I was brought up on a diet high in fruit and veg because my mother did not like meat. How much of nurture is nature is open for discussion.
I appreciate my good fortune. I have a DH who had to start taking medication at 40.