The LeBron James Diet Revealed
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This summer LeBron James slimmed down, losing some 15 pounds to ready himself for the upcoming season. His secret? Cutting carbs. The approach is nothing new: Two years ago, Dr. Cate Shanahan helped the Los Angeles Lakers switch from high-carb to low-carb and become so-called fat-burners, meaning that their bodies burns fat as a primary fuel, instead of carbohydrate. It's a fast way to lose weight while keeping muscle, a move that can help prevent injuries and boost energy reserves for players — and everyone else.

"The best way to make the switch at home is in baby steps over the course of a month," says Shanahan, author of Food Rules, A Doctor's Guide to Healthy Eating, and Deep Nutrition: Why Your Genes Need Traditional Food. To get started, stick to Shanahan's three guiding principles for designing low-carb meals (or go to her website, drcate.com, and click on "What's To Eat?"), and follow her four-week plan.

The Guiding Principles
1. 50/30/20: Aim to get 50 percent of your calories from healthy fats, 30 percent from protein, and 20 percent from healthy carbohydrates, ideally whole fruits and vegetables.

2. Embrace healthy fats: Going low carb means going high fat, and that means knowing the bad fats from the good. On the bad side, the only true villain is trans-fat, which sometimes appears on ingredient labels as "hydrogenated" or "partially-hydrogenated" oil, and which hides in a lot more processed food than you'd think, including most commercial salad dressings containing Canola and other vegetable oils (for a list of offending oils, check out Dr. Shanahan's website). On the good side, walnuts, almonds, avocados, olive oil, and fatty fish like salmon and sardines are the superstars. But don't be afraid of saturated fats from whole food sources like poultry, butter, and meat, especially grass-pastured. Numerous major studies have failed to find any link between saturated fat consumption and heart disease. Plus, says Shanahan, "Our bodies need these fats to help with nutrient absorption."

3. Don't snack: "A lot of people have been told you've got to suppress appetite by having frequent small meals throughout the day. But this keeps your insulin levels elevated, interfering with your switch to fat-burning." Don't starve yourself, but skip those hourly handfuls of almonds.

Four Weeks to LeBron Lean
Week One: Zero Carb Breakfast. For the first week, don't worry about changing your lunch and dinner habits. Just make breakfast a zero-carb meal — as in, two eggs scrambled in extra-virgin olive oil, topped with avocado. Or cold leftover chicken. You'll feel the difference immediately, in steady energy throughout the morning.

Week Two: Pack Lunch. When Dr. Shanahan says baby steps, she means baby steps. Before you worry about what goes into lunch, just get into the habit of packing lunch at home and bringing it with you to work. Mid-day restaurant and cafeteria meals are too often jumbo-sized and loaded with carbs and trans-fats.

Week Three: Low-Carb Your Lunch. Salad with chicken, tuna, steak, or even a hardboiled egg, plus copious walnuts, avocado, extra-virgin olive oil.

Week Four: Low-Carb Your Dinner. You've always wanted to eat this way: roasted, pan-seared, or grilled lamb/chicken/steak/fish, with copious sauce; heaping helping of vegetables or salad, maybe some cheese; fresh fruit dessert; but skip the rice/bread/pasta/chips.