I'm a big fan of the digestive system.
I've never thought about the ages of my readers.
If you are lucky enough to be successful, you get drawn further in and you stop paying attention to the stuff that matters.
Making books is hard work. Some books are, of course, more demanding than others.
Occasionally, I just need to escape from my work or be reminded of the comparative bliss of my own life, so I pick up a novel.