Better known examples of early descriptions of "foot qi" are by Chao Yuanfang (who lived during 550–630) in his book Zhu bing yuan hou lun (Sources and Symptoms of All Diseases) and by Sun Simiao (581–682) in his book Bei ji qian jin yao fang (Essential Emergency Formulas Worth a Thousand in Gold).In the late 19th century, beriberi was studied by Takaki Kanehiro, a British-trained Japanese medical doctor of the Imperial Japanese Navy. Beriberi was a serious problem in the Japanese navy; sailors fell ill an average of four times a year in the period 1878 to 1881, and 35% were cases of beriberi. In 1883, Takaki learned of a very high incidence of beriberi among cadets on a training mission from Japan to Hawaii, via New Zealand and South America. The voyage lasted more than nine months and resulted in 169 cases of sickness and 25 deaths on a ship of 376 men. With the support of the Japanese Navy, he conducted an experiment in which another ship was deployed on the same route, except that its crew was fed a diet of meat, fish, barley, rice, and beans. At the end of the voyage, this crew had only 14 cases of beriberi and no deaths. This convinced Takaki and the Japanese Navy that diet was the cause.
Dariers disease (DAR) is an inherited skin disorder that presents with multiple greasy, crusting, thick brown bumps that merge into patches.It is an autosomal dominant disorder discovered by French dermatologist Ferdinand-Jean Darier. Dariers is characterized by dark crusty patches on the skin that are mildly greasy and that emit a strong odor. These patches, also known as keratotic papules, keratosis follicularis, or dyskeratosis follicularis, most often appear on the scalp, forehead, upper arms, chest, back, knees, elbows, and behind the ear.Mild forms of the disease are the most common, consisting solely of skin rashes that flare up under certain conditions such as high humidity, high stress, or tight-fitting clothes. Short stature, when combined with poorly-formed fingernails that contain vertical striations, is diagnostic even for mild forms of DAR. Symptoms will usually appear in late childhood or early adulthood  between the ages of 15 to 30 years and will vary over the course of ones life. Signs and symptoms
Clinical symptoms  of the disease:Seborrhoeic areas
This is defined as areas where excess oil and sebum is released. Overall greasy or scaly skin either in the central chest and back or in the folds of the skin. Fragile or poorly formed fingernails
Nail disease leading to V-shaped nicks at the edge of the nail. Rash that covers many areas of the body
The rash is often associated with a strong unpleasant odor
The rash can be aggravated by heat, humidity, and exposure to sunlight.