While commanding four vessels sailing between England and India in 1601, Capt. James Lancaster performed one of the great experiments in medical history. Each of the seamen on just one ship—his own, of course—was required to sip three teaspoons of lemon juice per day. By the midpoint of the voyage, about 40 percent of the sailors on the other three ships had died, most from scurvy, while no one on his had succumbed to the disease.

This experiment is remembered less for its result—demonstrating the power of vitamin C-rich citrus fruits to combat scurvy—than its aftermath: It took the British Navy and perhaps a million deaths to adopt dietary regulations reflecting this simple, wondrous insight.

For all of its dazzling breakthroughs, modern medicine is still bedeviled by this achingly practical problem: how to identify and deliver the best healthcare practices to patients in a timely manner. Across the nation, hospitals are working to improve quality and affordability of care, recognizing the need to contribute to a healthier nation.

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