Both anorexia and bulimia increase the risk of death. In the developed world binge eating disorder affects about 1.6% of women and 0.8% of men in a given year. Anorexia affects about 0.4% and bulimia affects about 1.3% of young women in a given year.
If you are insisting that on average a page is 500 words or 4,000 words the equivalent of 8 pages. By simple math you saying the average book is 80,000-120,000 words, would mean on average a novel is 160-240 pages. These would be classified as short novels or more so novels for older kids or younger teens.
Novels for adults average around 100,000 words, and tend to have 250-350 words per page. Fantasy and science fiction can be a bit longer (or a lot longer, in some cases). I'm writing a book myself, I think a good average length for most book can range between 10,000 to 100,000 words.