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The stomach is an amazing organ. When you eat, its muscular walls stretch to hold up to three pints of food.

Unfortunately, stress can literally eat away at the body, says Dr. Oz. That's a leading cause of painful stomach ulcers, shown here at left. The black spots and discolored craters are signs of an overworked stomach. To protect your own stomach from these problems, try relaxing, stress-busting exercises like meditation.