NEW YORK — Not even McDonald's Corp. has an iron stomach when it comes to the global economic downturn.

The world's largest hamburger chain has thrived in boom and bust times by selling cheap eats and constantly updating its menu with popular items such as fruit smoothies and snack wraps. But the company is starting to show signs of wear and tear from global economic pressures, intensifying competition and penny-pinching customers who are eating out less often in some hard-hit regions around the world.

The Oak Brook, Ill.-based company said Monday that its net income fell 4 percent in the second quarter as a strong dollar ate into results.