The whey cure has been extensively practised in the mountainous regions of Germany and Switzerland and at various springs or baths, especially those of the alkaline waters, which latter are frequently mingled with the whey and drunk either warm or cold. The treatment is rigorous, and consists in confining the patient's diet largely to the use of about twenty ounces per diem of fresh milk whey. The principles of the treatment are essentially similar to those of the milk cure, but in whey the casein of the milk has been artificially removed to make cheese by the addition of rennet, the milk-curdling ferment.

Whey is made from the milk of several animals, such as the sheep, goat, mare, and ass, as well as the cow. It consists of milk sugar, albumin, substances resembling peptone, and a smaller quantity of fat with most of the lactic acid. It is whitish, translucent, and opalescent.

When milk has been standing for some time in the air it becomes contaminated with bacteria, which cause spontaneous coagulation, and whey is squeezed out of the contracting clot; but this is sour and not so good as that made by rennet. The percentage composition of whey is as follows:

Water..................................................... 93-31

Lactose................................................... 4-65

Fat....................................................... 0. 24

Proteid................................................... 0. 82

Lactic acid................................................ 0.33

Salt...................................................... 0.65

The whey cure is used for the treatment of Bright's disease and chronic catarrhal conditions of the alimentary canal. It is particularly recommended for chronic dyspepsia and chronic irritable cough accompanying catarrh of the respiratory mucous membranes.

It is said to improve the secretion in chronic bronchitis, and it increases the strength of the pulse, which is attributed to its potassium salts (May). If more than twenty ounces are ingested daily there is an increased peristaltic movement, with watery evacuations, colic, and dyspepsia.

Whey, like skimmed milk, is diuretic and sudorific. It therefore constitutes a useful beverage in fevers. The class of patients, many of them phthisical, for whom the cure is recommended at Ems, Ischl, Reichenhall, etc., are not fit subjects for a reducing diet, as they have little or no spare strength; they require rather abundant nourishment, owing to the catarrhal processes which affect the respiratory and alimentary passages. However, in such cases digestion and absorption are often greatly impaired, and this condition is found to be benefited by the use for a short period of the alkaline waters and whey. It is not safe to limit the diet exclusively to these fluids, and some nitrogenous food must be given, together with fresh fruit and green vegetables. In Switzerland and Germany the whey cure is often combined with the grape cure.