After
@Gardener1850 posted a photo of Denim from Mountain Crossings‘ Instagram, I looked at their other posts:
Mountain Crossings (@mountaincrossings) • Instagram photos and videos
I went as far back as December, 2017 and did not see a single person (male or female) who appeared as thin as one would at 5’8” and 83 lbs.
The National Missing and Unidentified Persons System (NamUs)
In all of the photos that I’ve seen so far of Denim, he looks to be in good health. As I understand, it isn’t uncommon for through hikers to lose significant amounts of weight. In Denim’s case, though, it just seems so extreme. There are several pictures of him at the link below:
Collier County Sheriff's Office
So unless he had an eating disorder, which I don’t believe we have seen any evidence of, my best guess is he suffered from a serious illness.
One of the possibilities I’ve considered is AIDS. Could it be that he shared the diagnosis with family, only to be ostracized over it?