As nutrition information became more widespread, people became more concerned with diet and health. Books on weight loss and healthy eating, written for the average person, appeared for the first time in the eighteenth century and have maintained a strong presence ever since.

Some of these books had a solid basis in science.  In the eighteenth and early nineteenth century, however, the majority were based on guesswork, intuition, and anecdote.  Religious belief also played a role, as the principles of the temperance movement bled into attitudes toward food in general.  As the nineteenth century progressed, misapplication of new discoveries led to fad diets and health food crazes, a phenomenon which is all too familiar today.