A friend recently told me she had lost 10lb in a 2 days by trying a new diet that was essentially starvation: 1 cup of black coffee with 1/2 cup of cottage cheese for breakfast, a lettuce leaf for lunch and an apple, and a small salad with chicken for dinner. "I'm eating absolutely no carbs!", she crowed. She's 170, trying to lose 30 pounds. She seemed excited and I...