Limey is a slang term, often pergorative, from Australia, New Zealand and South Africa applied initially to any British seaman and later to any Brit.
This could be because they were small and green by the time they got off the boat in Cape Town, Sydney or Wellington but it isn’t. It’s because of these:
In the 18th and 19th centuries limes saved as many lives of British naval personnel as penicillin did in the 20th century.
These small green fruit not only add a pleasant tang to grog but their high vitamin C content kept the dreaded scurvy at bay. Scurvy is a disgusting disease, debilitating, painful and unsightly, were the collagen forming connective tissue in humans begins to break down. Painful joints hamper movement, swollen and receding gums cause tooth loss. The patient is exhausted, emotionally unstable and eventually the internal organs begin to break down. And it began to affect the crew fast. Naval records show that on a six week tour of duty almost three quarters of the men would show signs of the disease if they had no access to fresh food.
It wasn’t until 1930s that we really got a handle on what causes scurvy and how it can be successfully treated, but long before that people had developed ways of handling it. Hippocrates described the disease in the 4th century BC and prescribed green vegetables as a cure. In the British navy it wasn’t all rum and flogging. Some captains were very concerned about their men and tried all kinds of cures, but it was found that citrus fruits, which were easy to transport and would stay good for a long time, were the best treatment. Imagine the atmosphere on the ship where the captain experimented with feeding his men large amounts of cabbage!
In 1753 naval surgeon James Lind published his Treatise of the Scurvy, recommending that limes be carried on all naval ships. The British Naval ignored his findings officially for several decades but individual captains followed the advice and once it had been proven to work the authorities began to provide limes or limejuice to all their ships.
And not just ships. I remember my grandfather telling me how his platoon was provided with crocks of lime juice during the Great War when they were in Palestine [and how one night the commissariat accidentally gave them the stone jar full of whisky that had been decanted for the officer's mess].
So soldiers, sailors and all kinds of travellers in hard places can thank the humble lime. Being called Limey is a small price to pay for keeping your teeth in your head.