Hasselbeck's book, "The G-Free Diet: A Gluten-Free Survival Guide," has appeared in the past month on several best-seller lists.
Hassett said in the lawsuit that she sent Hasselbeck a personal note and copy of her "Living With Celiac Disease" book as a courtesy after the television celebrity disclosed she had the illness last year.
Celiac disease is a digestive disorder associated with people who cannot digest gluten, a protein found in wheat, rye and barley.
Hassett said Hasselbeck's book "slavishly reproduces" lists and passages from her own work and includes inaccuracies about celiac disease that can be "misleading and dangerous" for people with the illness.
A lawyer for Hassett declined to comment Tuesday. Hasselbeck said in a statement that the allegations are baseless and she worked "diligently and tirelessly" on the book.
The lawsuit seeks to block the sale of Hasselbeck's book and asks that copies of it be withdrawn from distributors and stores.