Jessica Simpson's 100-Pound Weight Loss Secret Revealed – How She Did It

Jessica Simpson lost a staggering 100 pounds after welcoming baby number thee in March 2019. The "Dukes of Hazzard" actress has been turning heads for her whittled-down silhouette, with today bringing a major update – how she did it.

Jessica hasn't been too in-your-face with her slimmed-down body on Instagram. Less about the bikini pics and more about the family vibes, the 39-year-old's social media has been seeing her focus on her new status as a mom of three. Baby Birdie may be here, but she's got a hot mom who's now 100 pounds lighter.

Keep reading for the details.

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A Weight Watchers Plan And A 6-Month Journey

Jessica hired nutritionist Liz Josefsberg to help her shed the weight. Liz spoke exclusively to Hollywood Life this week, revealing both how she helped Jessica and some overall tips.

"During the time I worked with Jessica following the birth of her first two children, she was following Weight Watchers. She spent well over 6 months working off weight from her first and second pregnancies," Liz said.

"She ate regular meals throughout the day. Usually three times and a snack. The key for Jessica was moderation and learning to indulge intelligently," she added.

At Least 10,000 Steps Per Day

Liz further revealed Jessica's weight loss to be a combination of clued-up nutrition and exercise.

"Jessica loves to walk. She gets out almost every day to hit at least 10,000 steps. She loves it because she can do it anywhere, she can do it with her family and it helped her lose weight after every baby," she said of the star.

Fans were already wowed around the holidays when Jessica posted a snapshot from her ski trip – while Jessica herself didn't seem to do much skiing, she definitely showed off her new figure.

Hydration Is The 'Secret Weapon'

If you keep seeing Hollywood's fittest stars in gym run snaps with a bottle of water in hand, it's for a reason – hydration is key.

That's definitely Liz's view, with the trainer outlining why drinking plenty of water works.

“Hydration is a secret weapon for weight loss. In my book Target 100 I urge people to get in at least 100 ounces per day. Which might seem like a lot, but it is right for our bodies. Staying fully hydrated while losing weight is critical. Much of the overeating we do is mistaking thirst for hunger. If we can keep our bodies, which are made up of over 60% water, hydrated, they burn calories and metabolize food at an optimal rate!” she said.

Jessica Once Tipped The Scales At 240 Pounds

Jessica has been honest and open about her weight struggles over the years. September 2019 marked the big 100-pound loss as the star took to Instagram.

"6 months. 100 pounds down (Yes, I tipped the scales at 240)," she wrote.

"Even when it felt impossible, I chose to work harder," she added.

Speaking about the baby weight after welcoming baby number three, Jessica revealed the pregnancy had come with a giant appetite.

“When you’re pregnant, I gain a lot, I mean, a lot. I didn’t expect to gain as much with my third. I thought I’d learned my lesson, but apparently, that’s just the way God made me, very hungry and pregnant," she said.

If you're on the weight loss journey yourself, you've got Hollywood-recommended advice. If you know someone who's trying to lose, hit them up with this.