Final answer:
Captain James Lancaster was an early pioneer in the fight against scurvy by providing lemon juice to sailors, which later influenced the British Royal Navy's adoption of citrus fruits to combat the disease following James Lind's conclusive experiment and recommendations.
Step-by-step explanation:
Captain James Lancaster dealt with scurvy by conducting one of the first controlled dietary experiments in 1601 during his voyage to India. In his trial, he had the foresight to provide one group of his sailors with lemon juice as a dietary supplement while the others did not receive any. Miraculously, the group that consumed lemon juice remained healthy, thereby supporting the notion that citrus fruits could prevent and treat scurvy, although this was not widely recognized until much later when James Lind, a Scottish surgeon, published his work in 1753. It was Lind who famously conducted an experiment that conclusively showed that citrus fruits were effective in treating scurvy.
Lancaster's practice did not become widespread until after James Lind's formal experiment and subsequent publication, which recommended using lemons and limes to avoid scurvy. Lind's research is often cited as pivotal in the adoption of citrus fruits by the British Royal Navy, significantly reducing the incidence of scurvy among sailors.