When Zac Efron bulked up for his role as a marine in this month's The Lucky One, it was his nutritionist who got the kudos. "Working with David Allen Nutrition was amazing, and the plan was easy to follow," the 24-year-old actor says. Here, Hollywood's hottest dietary experts dish on what to eat and what to skip.

Colin Farrell
The Nutritionists: David Allen and Drew Prinz; davidallennutrition.com
Plan: Tests to check deficiencies and allergies, plus an eating plan
Cost: Premiere members pay $2,500 initially, $4,300 for tests, $1,700 per month.
You Get: Diet plan, meal delivery, unlimited access
Clients: Zac Efron, Colin Farrell, Vanessa Hudgens
Eat Less: Processed food
Eat More: Organic food
Snack: Walnuts, raw almonds, low-salt pistachios
Booze: Tequila, gin, vodka, no more than twice a week

The Nutritionist: Oz Garcia; ozgarcia.com
Plan: Teach clients to become their own nutritionists.
Cost: $20,000 for a year
You Get: Detailed tests, diet plan, and regular advice
Clients: Djimon Hounsou, Heidi Klum, Gwyneth Paltrow
Eat Less: Red meat, whether it's organic or not
Eat More: Seafood. "The fats are critical," Garcia says.
Snack: A chunk of dark chocolate
Booze: Maximum of four glasses of red wine a week

Djimon Hounsou

Audrina Patridge
The Nutritionist: Christine Avanti; christineavanti.com
Plan: Eat protein-carb combo or fat-carb combo every four hours.
Cost: $250 per hour
You Get: A two-hour consultation, diet and exercise plans
Clients: Chelsea Handler, Audrina Patridge, Jeremy Piven
Eat Less: "Fake foods," Avanti says.
Eat More: Coconut: the milk, water, meat, and oil
Snack: Honeycrisp apples with natural peanut butter
Booze: Maximum of four cocktails a week, using sake or vodka

The Nutritionist: Kimberly Snyder; kimberlysnyder.net
Plan: A whole-food, plant-based diet with a blended green-vegetable drink every morning
Cost: On request
You Get: A consultation and a meal plan, either cooked or guided by Snyder
Clients: Josh Duhamel, Chris Hemsworth, Channing Tatum
Eat Less: Dairy
Eat More: Greens
Snack: Rainforest Acai smoothie
Booze: Drink an occasional glass of red wine.

Josh Duhamel

Justin Timberlake
The Nutritionist: Donna Gates; bodyecology.com
Plan: A diet that's 80 percent plants and vegetables, with an emphasis on fermented foods
Cost: $500
You Get: A two-hour consultation and daily menus
Clients: Jessica Biel, Tia Mowry, Justin Timberlake
Eat Less: Sugar, refined carbs, industrial oils
Eat More: Fermented spirulina, a blue-green algae
Snack: None
Booze: Vodka or wine mixed with probiotic liquid, but only on special occasions

The Nutritionist: Kathy Kaehler; kathykaehler.net
Plan: Stock the fridge with fresh food each week.
Cost: $50 for a year
You Get: Weekly grocery lists, workout plans, menus
Clients: David Boreanaz, Kim Kardashian, Jennifer Lopez
Eat Less: Food made with unpronounceable ingredients
Eat More: Tomatoes, broccoli, kale, cauliflower
Snack: Homemade kale chips
Booze: Voli vodka, infused with electrolytes—maximum of three per week

Kim Kardashian

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