This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
Beri-beri is a form of multiple neuritis very rarely imported into this country by Chinese, Ceylonese, Japanese, or Philippine Islanders, who have acquired it in their native countries or on the voyage. It is characterised by anaemia, general cedema, and more or less stiffness and paralysis of the extremities, with dyspnoea and serous effusions. Sometimes there are muscular spasms.
Beri-beri has been attributed to the absence of fresh animal food from the diet, a sort of antithesis to the cause often assigned to scurvy. It has more specifically been attributed to the excessive consumption of rice and adzuki beans to the exclusion of other food; but these views are incorrect, for upon the authority of Baelz it is stated that the best fed and best nourished are frequently subject to the disease. In the Japanese navy, where the disease was formerly not seldom encountered, it has been practically exterminated by increasing the nitrogenous-food ration and lessening the carbohydrates.
The latest view of the disease is that it is not caused by bad food, but by a micro-organism, and that bad food and bad hygiene, are merely predisposing factors.