Actress and singer Jennifer Hudson put on quite the live performance on Good Morning America this morning, singing songs from her new album "I Remember Me." Check out those fit legs! Hudson also revealed that she'll be writing about her 80-pound weight loss in a new memoir that will share tips for others wanting to lose pounds and maintain a healthy weight like she has.

But J-Hud isn't the first celeb to write a weight-loss or diet book. Below are four other celebs who have penned books in the name of health and fitness!

Top Celebrity Weight-Loss and Diet Books

1. Alicia Silverstone. Author of The Kind Diet, Silverstone has written all about the joys of eating a vegan diet.

2. Alison Sweeney. Passionate about fitness, nutrition and raising a healthy family, Sweeney recently wrote The Mommy Diet for all the mothers out there looking to be a little more healthy!

3. Mario Lopez. Although we know him best from Saved by the Bell and Dancing with the Stars, Lopez is also a bit of a weight-loss expert. His book Extra Lean claims that it can help you lose 14 pounds in 14 days.

4. Bethenny Frankel. Bethenny Frankel has three books to her name: Naturally Thin, The Skinnygirl Dish, and A Place of Yes: 10 Rules for Getting Everything You Want Out of Life. Although her weight-loss methods have been somewhat controversial in the past, she's definitely a writer.

Jennipher Walters is the CEO and co-founder of the healthy living websites and A certified personal trainer, lifestyle and weight management coach and group exercise instructor, she also holds an MA in health journalism and regularly writes about all things fitness and wellness for various online publications.