Someone asked me if it is possible to recognize the sign of approaching death in the months before an undiagnosed person dies from an illness.
That is an interesting question and there are so many variables that there is no one answer. Here are some ideas to consider: Some people, who appear healthy with no evidence of disease, begin the dying process and go through the stages of dying without ever being diagnosed with a life threatening disease. They die and everyone is surprised. If you had asked them" are you sick", some might have said yes, other may have said no. Some may just have been in denial while others may have known how serious it was and just choose to do nothing.
Another possibility is a person was healthy and well, got an illness and even though they weren't "suppose" to die from the illness, they did. In that case they would not have entered the dying process before actual death.
While individual differences may be seen in the time of days to weeks before death, everyone who is dying will have the signs of approaching death that occur hours to minutes before death. Even the person dying from being hit by a car, a person I would say is having a fast death will show the signs of hours to minutes before death. In the last moments of life we all die similarly.
Often in hindsight we can see that indeed the person did show signs of approaching death months before actual death occurred. Eating decreased, sleeping increased; they withdrew from those around them. That would tell us the body had the disease long before it was if ever diagnosed.
In our personal situations we may never have an answer to the question did he know or had the process started months earlier. What I suspect is that at some time before we die we know that the moment has come. That knowledge may become real to us weeks, days, hours or minutes before death but there is a moment when without a doubt we know –this is what dying is like.