Ayurvedic Physiology

Eastern medicine provides an equally valid view, helping to complete our understanding and broaden our outlook.

Ayurveda, the ancient healing science of India, was devised thousands of years ago by sages and seers as a means to help suffering humanity. At this time there was no sophisticated technological equipment so that medical experts had to rely on the skilful manipulation of their own inner equipment - intuition, analytical reasons, intelligence and keen perception combined with observation of external disease manifestations. This fusion of the subjective with the objective is the meditative process. Out of this grew a system of great complexity and, if we believe the ancient shastras, great ability to cure disease.

The Doshas

Ayurveda regards food as the life of all faring creatures because it nourishes the components of the body. These components or doshas were of three main types:

  1. Kapha, translated as phlegm or mucus, but referring more to protoplasm, is the water which forms the ground structure of the body tissues. This fluid, sometimes referred to as soma, the water of life, is said to bind the limbs and organs, and provide the connecting, nourishing, developing and fortifying functions. It maintains the well-being of the body by its lubricating action. Its properties are cold, viscous and heavy, and it is related to tamo guna, the inertia principle. It is also associated with the power of perseverance.
  2. Pitta is translated as bile or gall and is closely related with temperament. It is the fire that exists in the body, acting on matter, animating and energizing it. This energy results in digestion, power of perception, body temperature, healthy appearance, emotions (fear, anger, joy), clarity, and also their opposite when pitta is not functioning properly. Its property is heat and it is related to rajo guna, the dynamic aspect of physical energy.
  3. Vata is translated as wind, implying movement. It is related to mental energy and is said to be the source of all structure and function, being represented in the body by the 5 pranas (i) udana -from the crown of the head to the throat, (ii) prana - from the throat to the heart, (iii) samana - from the heart to the navel, (iv) apana - from the navel to the toes, (v) vyana - pervades the whole body. Vata initiates upward and downward movements. It is the guiding force for consciousness and the sensation of the sense organs. As well as organizing the elements of the body, it is the storage battery for speech, the principle of synthesis, the cause of feeling and perception, and the source of excitement and stimulation. Vata fans the gastric fire and purifies the channels of the body. It is associated with sattva guna, the principle of balance, harmony and spirituality.

In order to maintain health and a good digestive system, the doshas must be properly balanced. The proportion and ratio of the various doshas changes with each season and also at different times of the day. Food must therefore be taken seasonally and in the correct amount and proportion for each dosha. This ensures that deficiencies and excesses are corrected, otherwise the doshas become unbalanced.

Digestive Fire

The digestive fire is essential for good health. When it becomes weak, indigestion and other disorders set in because of poor nourishment. Proper digestion requires that the various 'fires' of the body - the chemicals, acids, enzymes, and other digestive juices are in their correct proportion to maintain growth, strength, complexion, happiness and to prolong the existence of a healthy body.

The process of digestion occurs because of heat from various chemical reactions, water which softens the digesting food and air which fans the fire. Fire is the most important element out of which fine substances imbued with energy are produced. In medical terms this fine essence of food is composed of the amino acids, small sugars, etc. which are necessary for life.

Digestion follows a basic process. The ayurvedic and yogic terms used here must be seen in their correct relationship to the digestive system:

  1. The life breath, prana, seizes the food and sends it down to the stomach in the swallowing act.
  2. The digestive fire stirred up by samana burns and blazes forth in the stomach when nutritious food is taken. At the same time, the solid food is dissolved by liquid, gastric juices, and softened by oily matter (mucus). The digestive fire is said to be below and to cook the gastric contents like rice in a pot, converting it into essence (ras) and wastes (mal). A foamy reaction is produced by kapha (mucus) and after this the half digested food becomes sour (acids).
  3. It then passes out of the stomach and reacts with pitta (bile) from the liver.
  4. In the intestines the food is eventually dried by fire into a compact mass. During the process, vata (wind, prana) is produced by a bitter astringent reaction.
  5. The digested food travels by arteries to the heart from where it nourishes the tissues.
  6. The wastes of the body form in the digestive and metabolic processes. Faeces and urine come from food and water. Mucus is produced from the essence (ras) derived from digestion of food and is expelled in sneezing, etc. Bile (pitta) is derived from blood and expelled with faeces. The metabolism of flesh comes out in the ears as wax, the eyes as tears, the nostrils as phlegm. Fat waste comes out in sweat. Hair and nails come from bone. Oiliness in the skin comes from the marrow. These 'wastes' have their own specific function and thereby sustain the body as long as they are not produced in excess. When excessive, they pollute, weaken and cause disease.

Ayurvedic physiology goes on to state that each element of the food has its own specific elemental fire which can be interpreted to mean its own chemical reaction. Thus each element gives a still finer essence which is used to form another body tissue in the following increasingly more subtle order: essence is taken into the blood to produce flesh which then produces fat, bone, marrow, semen and finally energy (ojas). Each element also gives off a waste. The elements also retain their own substance which is driven by the pranas to their own specific destination.

Feeding the Fire

Food is fuel for the digestive fire, and therefore must be pure, well combined and in correct quantity. The amount of food one needs to eat depends on his digestive power. We must discover our own capacity - and set ourselves a standard amount to eat at each meal. Few people, however, can stop eating at the point of satisfaction or a little short of it. Constantly eating beyond this point vitiates the digestive fire. Undigested food is worse than no food and becomes a detriment to our health.

The body is the product of the food taken in, and all materials used as food are compounded from the 5 elements:

  1. Earth - used for building bones, nails, teeth, muscle, skin.
  2. Water - supplies substances for fat, blood, lymph, urine and sweat. These substances are inactive, soft, viscid and slimy.
  3. Fire - makes the body radiant.
  4. Air - maintains exhalation and inhalation, eyelid movements, contraction and expansion, excitement and incitement, and movement.
  5. Ether - supplies the pores and channels of the body.

Food is also divided into 10 dual qualities: (i) heavy-light, (it) cold-hot, (iii) oily-dry, (iv) mild-sharp, (v) compact-expansive, (vi) soft-hard, (vii) cleansing-slimy, (viii) smooth-rough, (ix) minute-gross, (x) solid-liquid.

Light and heavy are the most important qualities of food. Light food contains the elements of wind and heat and therefore is the best to maintain the digestive fire. It is less injurious when taken to satiety. Bitter tasting food is the lightest followed by pungent and sour tasting foods. Heavy food contains the elements of earth and water and therefore dampens the digestive fire. It is injurious when taken to satiation. Sweet tasting foods are the heaviest type.

Heating and cooling foods are also important in terms of maintaining digestion. Heat producing foods are saline, sour and pungent, while cooling foods are sweet, bitter and astringent. Oily foods contain the elements of earth and water, and are lubricating and cooling. Drying foods contain air; softening foods water and ether; cleansing foods air and earth. By understanding the qualities of the foods we are eating, we can manipulate and adjust the body's functions as we would the controls on a gas stove.

Practical Ayurveda

Ayurveda proposes a system of synthesizing food and digestion so that a balanced nourishing diet can be incorporated into our lifestyle. To ensure that your intake will balance the doshas, choose natural foods in season. To maintain the digestive fire, eat light meals and never overload. These simple rules are the basis for healthy living.

Two meals per day, one between 9 and 12 a.m. and the other between 5 and 7 p.m., are recommended. The appetite is stimulated just before meals with a little salt or ginger. Other recommendations are given regarding diet and how to sit at meals. Sitting cross-legged on the floor is said to enhance the energies in the abdomen by bringing them up from the legs. Moderation in drinking is also important - drinking before meals gives one a tendency towards thinness, and after meals towards stoutness. Further recommendations include careful hygiene of the mouth and a short walk after meals. By following these suggestions, digestion is improved.

The recommended diet includes: various cereals (especially rice and wheat), fruit, vegetables, nuts, ginger, garlic, salt, water (rainwater is said to be best), milk, oil, butter, honey, sugar cane. The amount of each depends on the individual capacity.

A balanced (sattvic) approach to diet helps us to balance our whole lives. It can actually be a means of enhancing consciousness if approached correctly. A simple, pure diet keeps our digestive system healthy and this has a positive, beneficial effect on our mental state, personality and interpersonal relationships. According to the Charaka Samhita:

Such diets and drinks whose colour, smell, taste and touch are pleasing to the senses and conducive to the health, if taken in accordance with the rules, in fact, represent the very life of living beings. The effect of the use of such diets and drinks can be perceived directly. If consumed according to rules they provide fuel to the fire of digestion, promote mental as well as physical strength, strength of tissue elements and complexion and they are pleasing to the senses. Otherwise they are harmful. (27:3)