It's my opinion that when you pass at first you keep your characteristics, like a habit, whatever they may be; old, armless, drinker, smoker etc until your belief system can accommodate the new possibilities. I think it's like radioman says. Everything is vibrations and that works out to be very vivid and whole and fulfilling, if you are able to believe it.
People eat when they first cross over, because they believe they are hungry and need to and want to, eventually the need or desire fades away.
If you read some of the old stuff on it, you'll hear about alcoholics, food addicts whatever get stuck in their rut of need and habit, they keep repeating the desire because it's never fulfilled, sometimes people don't even know theyre dead they are so consumed with their obsessions. That's also why places get haunted, the belief and need just a creates a rutted vibration. And Alzheimer patients can sometimes be confused when they first cross over but it fades away, it's like growing young-for everyone. Everybody gets help making the transition, if they are willing to listen.