Scottish surgeon’s mate James Lind carried out the first controlled medical trial by testing members of the UK Royal Navy in a bid to identify the cause of scurvy.
He chose 12 sailors who were already suffering from the disease and provided an identical diet and accommodation in order to eliminate factors associated with those influences. He then treated his patients with a range of substances including cider, vinegar, seawater, garlic and mustard. Those given citrus fruit recovered, thus linking the disease to a lack of vitamin C.
He published his findings in Treatise of the Scurvy in 1753. His work eventually led to sailors being given citrus fruits on long voyages to avoid the disease, which causes lethargy, anaemia, skin eruptions, sores and gum disease.
Photo from United States Department of Agriculture
A.D.A.M Medical Encyclopedia. Scurvy. Vitamin C deficiency; Scorbutus
Available at: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001395/