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A little secret to a six pack is that a prerequisite is getting below 10 percent body fat. This means you not only have to shed old fat, but you also have to prevent new fat from being packed on. Regularly eating hearty dark greens like kale and spinach offers two major appetite-suppressing attributes that are key to leaning out: They are mineral-rich, which helps turn off your hunger signal, and also full of fiber, which means they'll physically fill your stomach for longer periods. Greens don't have much in the way of carbohydrates, though, so a good strategy is to eat most of your greens later in the day, when your fueling requirements have already been met. A big green salad is ideal for dinner.