Who discovered how to prevent scurvy?

James Lind, a Scottish doctor, is usually given the credit for discovering in 1747 that scurvy, the disease that plagued many early European seafarers, could be prevented through the consumption of citrus fruits, even though he had no idea what the protective substance was.

But according to the controversial book, ‘1421: the year China discovered the world’, written by retired submarine commander Gavin Menzies and first published in 2002, this is an ethnocentric judgement. The book suggests that earlier, long distance Chinese voyagers were almost entirely successful in preventing the development of scurvy among their crews.

The author of ‘1421’ describes how, when Zhu Di, the third Chinese Ming Emperor, took the throne, he promoted from among his inner circle of eunuch advisers a man named Zheng He to be commander-in-chief of what was to become an enormous exploratory fleet of sailing ships.

This fleet set sail in 1421, travelling across to India, down the east coast of Africa and round the Cape of Good Hope. Other Chinese ships sailed across to America and rounded Cape Horn and yet others explored Antarctica and Australasia.

But the question the author poses was how could such long voyages be carried out with little or no evidence of serious sickness? The combined fleets were crewed by about 30,000 people, putting an enormous strain upon the food resources. Although they traded and foraged for fresh foods at their various ports of call, the long sea passages would have exhausted such supplies.

One of the Chinese fleets carried a historian, Ma Huan, whose diaries (“The overall survey of the ocean shores”, 1433) recorded how the fleets solved the problem.

Apparently, these diaries record that, unlike the supplies of weevil-ridden, ship’s biscuit carried on the later British fleets, the Chinese supply ships carried staples of soy beans, wheat, millet and rice, which could be stored for long periods without loss of nutritional value. These could be cooked fresh. In addition, the ships carried chickens, fed by the cereals, for fresh eggs and meat.

The soy beans were of particular importance. All the ships carried open tubs in which the soy beans were sprouted in sunlight, developing large quantities of riboflavin, niacin and, most importantly, vitamin C. Daily consumption of sprouted soy would provide more than enough vitamin C to prevent scurvy.

As Gavin Menzies suggests, providing soy bean sprouts would have required a considerable degree of foresight and organisation. In other words, he thinks, the Chinese mariners must have known about the prevention of scurvy long before 1421, perhaps from even earlier voyages.

The Chinese were known to have made several voyages by sea to India, for example, for purposes of trade before setting out on these longer journeys.

So, according to Gavin Menzies, the answer to the question of who discovered that scurvy could be prevented is not James Lind  or maybe Zheng He, but someone else before 1421. Who that was is not on record.