Dhatu refers to the body tissue, the building blocks of the human body in Ayurveda. Seven primary body tissue are described in Ayurveda in an order such that preceding tissue transforms to generate the next tissue.
The basic building blocks of our body consists of atoms, which combine together to form molecules, which further lead to cells. Cells further combine together to form body tissues or the Dhatu. These body tissues possess certain characteristics that differentiate them from others.
These characteristics also determine their functionality in terms of transformation and response to various stimuli such as food or neural signals.
Body Tissue Organization and Theory in Ayurveda
A unique feature of Sapta dhatus is that each human tissue is formed from the previous tissue in ascending order of complexity. Each body tissue or dhatu has its own Agni, digestive fire, or the energy of transformation, which determines metabolic changes in the tissues.
The strength of this energy or a specific dhatu’s digestive fire determines its quality and also the quality of the next tissue in line. Metabolic wastes and by-products are also formed in the process of transformation and generation of new tissues. These by-products are either used in the body or excreted via the excretory body system.
- Shukra – Reproductive tissues
- Majja – Bone marrow and Nervous tissues
- Asthi – Bone tissue including cartilages; supports Majja and Masma dhatu
- Meda – Fatty tissues that lubricate the body; consists of adipose tissue and provides support to Asthi dhatu
- Mamsa – Muscle tissues, provides physical strength and supports Meda dhatu
- Rakta – The Red Blood Cells in circulation. Rakta Dhatu nourishes Mamsa dhatu, all muscle tissues and provides physical strength and color to the body
- Rasa – plasma is derived from digested food. It nourishes every tissue and cell of the body
Transformation Process – Generation of Body Tissues
When we ingest food, it gets digested and converted into smaller metabolites inside our gastrointestinal tract. This conversion is governed by the central digestive fire, also termed as Jathragni, or the basal metabolic rate.
Various secretions such as bile juice, pancreatic fluids, and digestive enzymes get mixed up with ingested food to form a chyme-like material known as ahara rasa or food essence. This material is converted into Rasa Dhatu or Plasma tissues .
Rasa dhatu is transformed by the Rasagni or the digestive fire of Rasa Dhatu into Rakta dhatu, the red blood cells. This is the second fundamental body tissue. Rakta dhatu gets transformed into Mamsa Dhatu, muscle tissues by Raktagni or the digestive fire of Rakta Dhatu and so on.
The dhatus or the body tissues support and derive energy from each other. Any disorders in the preceding dhatu can affect the quality and quantity of the succeding dhatu. For instance, interference in the manufacture of the plasma affects the quality of the blood, which in turn affects the muscle.