I’ve been wondering this lately; someone has to have written a novel that truly captures what it’s like to be old. For the sake of argument, let’s define old as “senior citizen” age - 70+, in the twilight years of life, etc.
What really captures what it truly feels like, how thought processes are, feelings, memories, etc.?
The non-supernatural parts of Stephen King’s “Insomnia” are good at that. The protaganist is in his 70’s.
Memento Mori
Praise the Human Season
There are two books by William Boyd – The New Confessions (1997) and Any Human Heart (2002) – that follow a character (different ones) from youth until death. I recall the “old age” parts near the end as having verisimilitude.
Carol Shields’ The Stone Diaries, the life story of Daisy Goodwill, evoked for me the feeling of getting old.
I am not an authority, but Barney’s Version by Mordecai Richler seems pretty accurate.
I’d add McMurtry’s “The Evening Star” about the middle-aged rise and elderly but feisty decline of his famous character, Aurora Greenway (“Terms of Endearment”). This book was compassionate and very tender in its handling of the aging of Aurora’s character and her many (and final) tribulations.
–Beck
I am not yet an old person, but I was once a social worker with a caseload of elderly people.
They aren’t a uniform lot. I met some people who gave me a very good feeling about what it could be like to be 90, but I also met some folks who were dour and half-dead and ready to die the rest of the way before they were out of their 60s.
I did think Insomnia rang true in its depiction of the main character.
This is something that should be underlined. I imagine that being old is something that’s as different for everyone as being young is.
That said, I recommend The Stone Angel, by Margaret Laurence.
The protagonist (Hagar Shipley) is a fully realized character and totally genuine as a confused but proud old woman and (through analepsis) in youth and middle age.
It’s a damned fine novel, too.
I was going to suggest a different Don Robertson title – The Ideal Genuine Man. (I have Praise the Human Season but haven’t read it yet.)
::doing the happy dance - another Robertson reader!::
I don’t know what “analepsis” is, but when I read this book, I totally wanted to grow up to be Hagar. I’m almost there.
Arnold Bennett’s The Old Wives’ Tale.
As the first review says, “…there is only one villain, and yet, he is perhaps the most powerful and chilling of all villains, Time. His grasping, clutching, suffocating presence is ever felt throughout the book, and looms even larger once that final page is turned.”
Much of Samuel Beckett’s work–especially his later stuff*–deals with, among many other things, the tendency of the human body to betray its master by growing increasingly decrepit. Molloy, my favorite Beckett, treats of this theme pretty extensively, literally as well as metaphorically.
One of my favorite “lighter” reads is a book that is WAY more obscure than it should be. It should be a bestseller, and it would make a BRILLIANT vehicle for Shirley MacLaine and, well, some other old broad: The Widows’ Adventures, by Chicago’s Charles Dickinson. It’s a tremendously touching and real portrait of two old sister, Ina and Helene, who love each other and hate each other, who decide to drive from Chicago to Los Angeles. Just the two of them. Ina has never learned to drive, so Helene, who has always loved being behind the wheel, will drive. They have to drive at night, and by side roads, and very slowly, because Helene is blind, and Ina must guide her along the road every inch of the way. As gimmicky as that sounds, it absolutely works, and you never doubt it for a minute. We learn a lot about the women, their lives, their children, their relationship; they learn a great deal new about each other as well. I really can’t recommend it enough, and I cannot for the life of me figure out why it hasn’t been made into a movie. Come on, an old broad buddy/road movie? It’s a natural.
Sorry, AuntiePam, my pretense again. “Flashback” is probably a better word to use, but it always makes me picture that cheesy wavy video effect.
That aside, “almost Hagar” is a surprisingly attractive self description. 
I read, and was profoundly moved by, Any Human Heart. In fact, it made me weep like a baby. Neither I nor William Boyd truly know what it’s like to be elderly, but as far as I can tell it’s a fantastic approximation. Highly recommended, and I’m going to get the other one now.
I’m on this. Found a copy at Amazon for twenty cents. Crows is one of my favorite books, and I’d resisted looking for more Dickinson, until now.
Larry Mudd, yeah. 
And wouldn’t Almost Hagar be a great screen name?
Need it be a novel? While at the tender age of 27 I’m probably not well-qualified, but China Mieville’s story “Different Skies,” in the collection Looking For Jake, rang rather true for me.
Praise the Human Season is a tearjerker and EXCELLENT! I’l have to read The Ideal Genuine man.
Only a section in a longer work of linked novellas, but the chapter “The Economics of Coth” in James Branch Cabell’s <b>The Silver Stallion</b> is an incredible portrait of the decline of a proud man.