Metabolism explained " Prakapa & Vipaka "

There are two phases of digestion explained elaborately in Ayurveda. One of them is known as Prakapa metabolism in digestion. This phase involves the conversion that takes place within the gastrointestinal tract, up to and including the absorption through the intestinal walls. The gastrointestinal tract and its surrounding area are mainly divided into three sections as per the specific dosha functions governing the concerned area. The upper portion of the gastrointestinal tract is dominated by the cohesive, lubricating and liquefying functions of Kapha dosha. The middle part is subjugated by the transformative actions of Pitta dosha and the lower zone is dominated by the separating, absorptive and drying processes of Vata dosha.



Prakapa digestion starts with eating and swallowing. Ayurveda defines that the three stages of the Prakapa metabolism in digestion are referred to as the three transient phases of metabolism. Each dosha has associated with a prominent taste or rasa. The basic natures of the five elements and their combinations produce six different tastes and these are sweet, salty, sour, pungent, astringent and bitter. The tastes hold special significance in Prakapa digestion. As the food particles moves through the three particular dosha stages, it takes on the taste associated with the dosha particularly governing the concerned zone. The basic tastes will predominate regardless of the taste the food has at the time it was eaten. The food just after consuming enters the kapha zone, which is the first stage of transient metabolism. At this stage it gets moistened and liquefied. As because of the watery secretions is in abundance at this particular zone, the food increases in volume. It acquires a principally the sweet taste and at this initial stage of Prakapa digestion, the food becomes even sweeter.

In the second phase of Prakapa metabolism, the qualities of Agni begin to take over. In this mid-zone temperature level rises because of the conversion process that takes place here. The food particles which are bound together and liquefied by kapha`s action combine with the acid secretions from the glands present in the pitta zone. They are now broken down and homogenized and they can not be recognized s distinct food particles any longer. Moreover, the food mass takes on the sour taste that is associated with the pitta dosha. At the final stage of Prakapa or transient metabolism, the changed food mass takes entry into the vata zone. Here the process of absorption starts. Under the influence of the vata dosha, the nutrient portions of the food substance are separated from the parts which are not used. In the entire process, water gets separated from earth and the food volume decreases. Influence of Agni is still active at the last stage. The food mass becomes pungent in taste.

Nature of Prakapa Metabolism in Digestion
In Ayurveda, it is defined that the entire metabolic sequence of the human body is a universal phenomenon. As the food substance moves through the three different phases of Prakapa digestion the body actually feels the influence of every single as it consecutively dominates the process of digestion. For instance, in the very first phase of Prakapa digestion, the pressure of kapha forms a sleepy and heavy feeling. When the food leaves the stomach and reaches the zone of the pitta, the transformation processes raise the body temperature giving a warm and thirsty feeling. When the food mass enters the final and the last stage, the influence of vata stimulates the body for some activities.

The length of time taken for food to pass through each of the single phase of Prakapa metabolism is considered as significant as it is a clue to the source of the digestive problem. Moreover, foods which are too sweet, oily, cold or heavy take longer time to digest as they demand stronger digestive fire. In the same manner, eating large quantities of food also produce the similar effect. In general, it is said in Ayurveda that if the digestive fire is strong then the time it will take to digest the food will be comparatively shorter. On the other hand, if it is sluggish and weak, it will take pretty longer time.

Vipaka

Vipaka metabolism is also known as the post absorptive digestive process. In Ayurveda, it is stated that the initial stages of digestion prepares the food to be assimilated by the dhatus in the seven metabolic stages, which are collectively known as Vipaka metabolism. The process of digestion is not complete when the food passes the three significant zones of the gastrointestinal tract. The nutrients that result from Prakapa digestion are not in a form that can be absorbed by the dhatus. As each and every single dhatu has a different structure and function in the body, it demands its own metabolic process, the one that can transform the raw nutrients into a form that can be utilized for its particular nutritional requirements. Vipaka that is the post absorptive digestion starts once the nutrition are absorbed into the body from the area adjacent to the intestines. This phase of digestion continues the process of conversion through a fixed sequence of increasingly refined digestive process.

Each dhatu has its own metabolic dhatu that helps in converting the raw foodstuffs sent from the previous stage of digestion into precise nutrients that are needed by the body. Each of the seven dhatus gets nourished in the same sequence that is in the way it develops in the body. In Ayurveda, it is stated that Prakapa metabolism transforms the food into a particular form that can be acted upon by the doshas. It is the rasa metabolism that starts the Vipaka metabolism in the body and it produces that substance which is capable of sustaining the rasa dhatu that comprises the nutrient fluid and plasma. Rasa metabolism chooses those parts of the processed food stuff that will have a nourishing effect. Kapha is responsible for binding together whatever is inoperative and the Vata takes it back to the gastrointestinal tract for exclusion as mala. Rasa dhatu only absorbs that much portion of the food which is required by the body for nourishment.

Each dosha plays a significant role in the entire process of Vipaka digestion and each of them works in precise coordination with the other two in order to successfully accomplish this digestive process. Vipaka digestion ends when all the physical substances and the structures of the body have already received enough nourishment. The final stage of this metabolic process takes place in Shukra dhatu and it forms `ojas` that represents the essence of the entire digestive process. According to the concepts of Ayurveda, it is the factor that is responsible for the body`s immunity to diseases. Ojas also allows every cell in the body to function in direct communication with the nature`s limitless intelligence. It also generates coordination and harmony among the major aspects of human life.

Ayurveda always places huge emphasis on efficient and strong digestion because of its vital importance for physical well being. It states that healthy digestion is required for connecting the parts of life to their basis. Any minor breakdown in the activities that nourish dhatu will inevitably weaken the health of the dhatus in the developmental process.

Vipaka metabolism in the digestion is really significant as it helps in maintaining a balanced relationship among the body`s innate healing intelligences.