Drew Barrymore Shed 20 Pounds by Adding One Ingredient to Her Diet

Gwyneth Paltrow avoids soy.

"Soy is not a health food," Gwyneth's health coach Dr. Frank Lipman said. "If it's not fermented, I don’t recommend it. And again, most soy is genetically modified. For some people, grains in general. It's tricky after sugar and gluten. You've got to find a way where it doesn't feel like you're on a diet and you don't feel deprived."

Dr. Oz says you should avoid high fructose corn syrup in beverages like soda.

"It's not very good for you," he said on The Oprah Winfrey Show. "It blocks the ability of a chemical called lectin, which is the way your fat tells your brain it's full.... [If you're drinking soda with a meal], you'll consume extra calories because of this."

Carrie Underwood doesn't eat bread.

"I'm vegan and I love bread, but recently, I started making dinner a breadless meal," she told Shape magazine in 2015. "I'll have a bowl of oatmeal for breakfast, and I'll make a sandwich on Ezekiel bread for lunch, but in the evening I'll have protein and vegetables and no bread. When I wake up, my belly is flat!"

Alec Baldwin doesn't eat sweet and sour sauce.

When a trip to the doctor revealed the 59-year-old actor's sugar intake was at "pre-diabetic" levels, he started cutting out sugar, including "his beloved sweet-and-sour Chinese sauce, a sugar-fest," according to his wife, Hilaria Baldwin in her book, The Living Clearly Method.

Taylor Schilling doesn't drink fruit juice.

"I don't roll with the juice cleanses," she said. "I will never do that. I like chicken and beans." Considering that some fruit juices have as much sugar as soda, it sounds like she's on to something.

Chopped host Ted Allen doesn't eat frozen pizza.

“People should not eat frozen pizza. Ever. It’s terrible,” he said. “All of it’s awful, just packed with the lowest quality ingredients, lousy sauces, and they’re overpriced for what they are. It’s not a good product. There’s so much sodium, so many calories and artificial crap and preservatives.”

Tia Mowry cut out processed foods.

"As I started to make healthier choices in my own life, I saw things — like my endometriosis or my migraines — be put at bay," she said. Although she also doesn't eat milk or gluten, processed foods in particular contain unnatural ingredients that can cause weight gain.

John Goodman dropped 100 pounds by not eating sugar.

“I know it sounds sappy, but it was a waste,” he said about this couch-potato days. “It takes a lot of creative energy to sit on your a-- and figure out what you’re going to eat next … I wanted to live life better.”

He also excercises on top of dieting.

Danica McKellar keeps her figure trim by cutting out dairy.

“I don’t eat gluten, I don’t eat dairy, I don’t eat sugar really, and the only thing I drink is water,” the Wonder Years star said in 2014. “I eat really, really clean. I’m very strict.”

Kirstie Alley doesn't eat cheese.

The 66-year-old finds cheese too triggering to eat, prompting her to want to eat more. Her solution? To cut out cheese entirely.

“I’m much more disciplined,” she said. “I discovered triple cream Brie cheese this year and I discovered how good that was, so I [don't keep it in the house]!"

Jonathan Knight lost weight after he stopped eating meat.

"Just seeing how animals are raised and the slaughterhouses freaked me out,” the New Kids on the Block star said. After cutting meat from his diet and eating more vegetables, the pounds started melting off. “Seven months later, I'm down to 175 pounds and I didn’t work out or anything."

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