Hollywood star Cameron Diaz has taken a page from her good friend Gwyneth Paltrow and written a book on nutrition and health.

"The Body Book: The Law of Hunger, the Science of Strength, and Other Ways to Love Your Amazing Body" is due out December 31 and available for preorder via Amazon for $16.43.

Rather than focusing on a seven-day or month-long diet plan, the book "offers a holistic, long-term approach to making consistent choices and reaching the ultimate goal: a long, strong, happy, healthy life," a promo reads.

Diaz, 41, also focuses on debunking the hype around food groups, explains the benefits of vitamins and minerals, and delves into the rationale of embracing "the instinct of hunger to satisfy it with whole, nutrient-dense foods."

A renowned fitness fan and surfer, Diaz also focuses on the much-needed benefits of a daily workout to stave off disease and boost mood and energy levels.

But she admits that she wasn't always such a health eater. "If you are what you eat, I was a bean burrito with extra cheese and extra sauce, no onions," she said, adding that her formerly poor diet negatively affected her skin and body. To make changes, she began learning about nutrition and well-being, and says her new book is a result of all that she's learned.

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  • Christina Aguilera

    The singer and Voice coach was strewn across tabloid covers last year for her weight gain, and a source noted to Us Weekly <a href="http://global.christianpost.com/news/christina-aguilera-weight-loss-voice-star-lost-over-20-lbs-all-on-her-own-101069/" target="_blank">that it made her "depressed."</a> (Shown here January 9, 2013)

  • Christina Aguilera

    But thanks to <a href="http://www.ibtimes.com/christina-aguilera-weight-loss-singer-shows-slim-body-voice-promotional-event-photo-1362357" target="_blank">working with a personal trainer</a>, according to the International Business Times, she's lost 20 pounds and seems healthier - as well as happier - than ever. As she told Extra, she did it through "<a href="http://www.extratv.com/2013/11/26/christina-aguileras-tips-for-slimming-down-laughter-happiness-and-yoga/" target="_blank">Laughter, happiness, breathing</a>, and I did some yoga.” (Shown here November 24, 2013)

  • Nicole "Snooki" Polizzi

    Her 4"9 frame makes it pretty easy for this reality TV star to both put on and take off weight, and before her pregnancy (and on Jersey Shore), she weighed approximately 146 pounds. (Shown here February 15, 2011)

  • Nicole "Snooki" Polizzi

    Now with a 42-pound loss, she's looking muscular and strong (and in <a href="http://www.dailymail.co.uk/tvshowbiz/article-2381549/Snooki-shows-dramatic-50lbs-weight-loss-bikini-splashes-Jersey-Shore-fiance-son.html" target="_blank">these beach shots of her family</a>, like she can really swing that kid!).

  • Beyonce Knowles

    There's never really been a time when Beyoncé hasn't looked amazing (see <a href="http://www.nydailynews.com/new-york/class-ward-lenox-hill-hospital-article-1.1186213" target="_blank">post-birth of Blue Ivy photo</a>). Beyonce Knowles attends The Metropolitan Museum of Art's Costume Institute benefit celebrating "PUNK: Chaos to Couture" on Monday, May 6, 2013, in New York. (Photo by Evan Agostini/Invision/AP)

  • Beyonce

    However, as 2013 has gone on, she's looked better and tougher than ever, showing off her amazing abs in her <a href="http://music-mix.ew.com/2013/12/13/beyonce-new-album-videos-songs/" target="_blank">just-released videos</a>. Obviously this woman knows how to take care of herself, even with an insane tour schedule. (Shown Dec. 3, 2013)

  • Naya Rivera

    The Glee actress has always been able to rock the short cheerleading skirts that are part of her costumes, but much as her character changed this season on the show ...

  • Naya Rivera

    ... so did her look, which became far leaner and more sultry. And yes, with more skin.

  • Kelly Clarkson

    Singer Kelly Clarkson has been harassed about her weight almost since winning her American Idol season in 2002, with many critics (like say, <a href="http://www.digitalspy.ca/celebrity/news/a510027/miley-cyrus-friends-slam-fat-bitter-kelly-clarkson-over-vmas-remark.html" target="_blank">Miley Cyrus' friends</a>) berating her size. (Shown here February 12, 2012)

  • Kelly Clarkson

    And though as of November, the star is now pregnant (and told Parade magazine, "Everybody calls me fat all the time, so I can’t wait to have a reason, instead of everybody just being a jerk!”), she was looking pretty bodacious in 2013. (Shown here February 10, 2013)

  • America Ferrera

    The Ugly Betty (or Good Wife, if you prefer) actress has always been gorgeous, but knows there's plenty of criticism out there. As she told Cosmopolitan for Latinas, "<a href="http://thecelebritycafe.com/feature/2012/10/america-ferrera-speaks-out-about-dieting-and-weight-loss" target="_blank">How much time have I wasted on diets</a> and what I look like? Take your time and your talent and figure out what you have to contribute to this world,” Ferrera says. (Shown September 17, 2012)

  • America Ferrera

    These days America is looking better than ever, with <a href="http://www.usmagazine.com/celebrity-news/news/america-ferrera-graduating-from-college-after-10-years-2013145" target="_blank">a college diploma under her belt</a> to boot. (Shown Nov. 18, 2013)

  • Hilary Duff

    Hilary Duff was one of the few Hollywood moms who was very vocal about taking her time to lose the 50 pounds she gained while pregnant (son Luca was born in March 2012), and for that, we applaud her. (Shown December 7, 2012)

  • Hilary Duff

    As we do for how awesome and healthy she looks now, having started boxing with a personal trainer in late 2012 and rocking some serious shoulders this year. (Shown November 6, 2013)

  • Graham Elliot

    The MasterChef judge was well aware of his weight issues, <a href="http://www.today.com/food/graham-elliot-being-healthy-my-family-was-trigger-losing-130-2D11722244" target="_blank">tipping the scale at 400 pounds</a> around the time his third son was born — and he decided to do something about it. (Shown March 7, 2013)

  • Graham Elliot

    Elliot underwent a gastrectomy to reduce his stomach size and lost 128 pounds in four months, recently tweeting this picture on his Twitter. He's taken up exercise and <a href="http://www.huffingtonpost.com/2013/12/04/graham-elliot-weight-loss_n_4385371.html" target="_blank">ran his first 5K in November</a>.

  • Britney Spears

    The teen star turned mom of two quite fairly looked prettily average for the past few years. (Shown May 11, 2013) CARSON, CA - MAY 11: Singer Britney Spears onstage at 102.7 KIIS FM's Wango Tango 2013 held at The Home Depot Center on May 11, 2013 in Carson, California. (Photo by Kevin Winter/Getty Images)

  • Britney Spears

    But with the launch of a new album and <a href="http://www.youtube.com/watch?v=pt8VYOfr8To" target="_blank">intense video</a>, her body is toned and strong - no matter how you feel about Work B*tch, there's no denying it's inspirational on that front. (Shown Sept. 21, 2013)

  • Queen Latifah

    In the past year, Queen Latifah has been working with a personal trainer, not to necessarily lose weight, but <a href="http://www.fitnessmagazine.com/workout/real-plans/celebrity/queen-latifahs-cardio-workout-plan/" target="_blank">tone and strengthen</a>. (Shown January 9, 2012)

  • Queen Latifah

    And the 5"10 singer and actress certain succeeded, looking completely stunning in form-fitting dresses throughout 2013. (Shown Oct. 26, 2013)

  • Khloe Kardashian

    Alright, we're just going to say it and get it over with — it's tough to "keep up with" your sisters when they're Kim and Kourtney Kardashian. (Shown March 2, 2013)

  • Khloe Kardashian

    But Khloe Kardashian could arguably top even her older sister's post-baby weight with how amazing and healthy she looks. Apparently, she <a href="http://hollywoodlife.com/2013/05/30/khloe-kardashian-today-show-dress-weight-loss-picture/" target="_blank">lost 25 pounds this year</a>. (Shown Dec. 11, 2013)

  • Jordin Sparks

    Singer Jordin Sparks made a commitment to weight loss over the long-term, <a href="http://www.redbookmag.com/health-wellness/advice/jordin-sparks-weight-loss-tips#slide-1" target="_blank">telling Redbook she lost 50 pounds over 18 months</a>. (Shown December 16, 2012)

  • Jordin Sparks

    This year, it looks like she's worked even harder on her body, with the gorgeous 6"0 beauty making us incredibly jealous of her arms (and legs!). (Shown Dec. 10, 2013)

  • NeNe Leakes

    Real Housewives star and Glee actress NeNe Leakes happily admits <a href="http://www.dailymail.co.uk/tvshowbiz/article-2491659/Nene-Leakes-youthful-natural-make-shows-weight-loss.html" target="_blank">to liking being "curvy."</a> (Shown Jan. 13, 2013)

  • NeNe Leakes

    But with <a href="http://www.dailymail.co.uk/tvshowbiz/article-2452832/How-NeNe-Leakes-lost-20lbs-summer-wedding.html" target="_blank">the 20 pounds she dropped</a> for her wedding in June, she looks just as confident as ever — and apparently far more confident in form-fitting clothes. (Shown Nov. 7, 2013)