by: Dr. J. H. Kellogg

It may safely be said that no other element in nature sustains so important relations to the living system as does pure water. An individual will live much longer on water alone, than if deprived of drink. Water constitutes a large proportion of all our food, varying, in grains and vegetables, from fifteen to more than ninety percent. If the water thus contained in solid food were wholly removed, an individual would doubtless be enabled to subsist longer on water only than on solid food so treated. Though water undergoes no change in the body, and hence takes no part in the development of force, it is absolutely essential to the performance of the vital functions, being necessary to enable the various organs to perform their offices in the maintenance of the vital activities.

The circulatory system is especially dependent upon this element.  Water is the menstruum which floats the blood corpuscles and the varied nutritive and excrementitious elements which form the blood. By its aid, the nutrient particles destined to enter into the structure of the body are conveyed to the most minute and remote fiber of the intricate human mechanism where repair or growth is demanded.  No other element in nature is so well suited to this exact purpose as water.  It is so limpid and mobile that it can circulate through the most delicate capillaries without friction, and can even find its way, by osmosis, into parts inaccessible by openings.


Water is continually passing away from the body. The dry air entering the lungs by respiration absorbs it from the moist surface of the pulmonary membranes.  A large portion is lost by evaporation from the skin, upon which it is poured out by millions of little sewers, the perspiratory ducts, for the purpose of washing away impurities from the system. The kidneys remove a considerable quantity, with poisonous excrementitious elements in solution.  Through still other channels water is removed, aggregating, in all, the amount of five pints in twenty-four hours in the average individual.  This loss must be made good, in order to preserve the requisite fluidity of the blood; and nature expresses the demand for water by thirst.

Some people rarely drink liquid of any kind. Others consume several pints in a day. The nature of an individual’s occupation will in a measure determine the amount of drink required. Stokers, glass-blowers, and others whose vocation necessitates profuse perspiration, require more water than others.  It will be noticed, moreover, that the character of the diet has much to do with the demand for drink. Those who subsist mostly upon fruits and grains, and other vegetable productions, avoiding the use of stimulating and irritating condiments, require little or no addition to the juices contained in their food. Those who pursue an opposite course in dietetics, using largely animal food, salt, pepper, spices and other condiments, and perhaps taking a little wine or something stronger for their stomach’s sake, are under the necessity of taking considerable quantities of fluid in addition to that provided by their food.

Water is the only substance which will quench thirst.  Beverages which contain other substances are useful as drinks just in proportion to the amount of water which they contain, and are unwholesome just in proportion as the added elements are injurious.


The evaporation of water from the surface of the human body is one of the most admirable adaptations of means to ends exhibited in animal life. All of the vital activities in constant operation in the body occasion the production of heat. Sometimes the amount of heat is greater than is needed, and so great as would destroy the vitality of certain tissues if it were not speedily conducted away.  By evaporation of water from the skin, this is accomplished.  When external heat is great, perspiration is more active than when it is less, and thus the temperature of the body is maintained at about 100 degrees F. under all circumstances. By this wonderful provision of nature, man is enables to exist under the great extremes of heat and cold presented in the frigid regions at the poles and the torrid climate of the equator.  By the aid of clothing, human beings have survived a continued temperature of 60 degrees to 100 degrees below zero; and, by the protective influence of evaporation, an average of 100 degrees above zero has been endured in tropical climes.


Every thought, every movement, the most delicate vital action, occasions the destruction of a portion of the living tissues, which is thus converted into dead matter, and becomes poisonous.  Many kinds of poisonous substances are produced within the body in this way. Some of them are very deadly, and must be hurried out of the system with great rapidity, as urea and cholesterine. Here the marvelous utility of water is again displayed.  It dissolves these poisons wherever it comes in contact with them, and then as it is brought by the current of the circulation to the proper organs – the kidneys, liver, skin, lungs, and other emunctroies – it is expelled from the body, still holding in solution the animal poisons which are so rapidly fatal if retained.


Neglecting to keep the skin active and vigorous by frequent ablutions is one of the most prolific causes of nearly all varieties of skin diseases, which are too often aggravated by gross dietetic habits.  The relation between the cutaneous function and that of the kidneys is so intimate that neglect of the kind mentioned, resulting as it must in obstruction of function, is a very common cause of most dangerous disorders of the renal organs. Inactivity of the skin is also very commonly associated with dyspepsia, with rheumatism, gout, hysteria, and other nervous derangements.  It is also a not uncommon cause of bronchial and pulmonary affections. It is quite evident, then, that the proper and most efficient means of preventing these diseases is to maintain the functional vigor of the skin by the proper application of water.

The value of water as a prophylactic, or preventive, of disease, was recognized by the ancients, and the bath was employed by them to an extent which has never been equaled in modern times. The great Hebrew lawgiver, Moses, enjoined upon his followers the most scrupulous cleanliness, making bathing a part of their religious duties. His example was followed by the ingenious founder of Mohammedanism, who required his disciples to bathe before each of their five daily prayers. Among the Greeks, and especially the temperate Spartans, the bath was regarded as one of the most essential means of securing physical health.