The Sapta Dhatu – Seven body Tissues
The “Dhatus” are the basic varieties of tissues which compose the human body. The word “dhatu” comes from a Sanskrit word which means “that which enters into the formation of the body”; the root Daa (dha) means “support, that which bears”. The primary Dhatus are seven in number. They are:
- Shukra – reproductive tissues
- Majja – bone marrow and nervous tissues
- Asthi – bone tissues including cartilages; supports Majja and Masma dhatu
- Meda – fatty tissues that lubricates the body; consists of adipose tissue and provides support to Asthi dhatu
- Mamsa – muscle tissues; provides physical strength and supports Meda dhatu
- Rakta – formed/circulating blood cells; nourishes all muscle tissues Mamsa dhatu and provides physical strength and colour to the body
- Rasa – plasma is derived from digested food; nourishes every tissue and cell of the body
A unique feature of Saptdhatus is that each human tissue is formed from the previous tissue in ascending order of complexity. Each tissue type “dhatu” has its own “agni”, which determines metabolic changes in the tissues. And forms by-products, which are either used in the body or excreted.
When food is ingested it is digested until, in the small intestines, it becomes a liquidy, chyme-like material known in Ayurveda as “ahara rasa” or food essence. With the help of “ahara rasagni”, this “ahara rasa” is converted into Rasa dhatu (blood plasma)–the first and most simple tissue. Rasa dhatu–catalyzed by Rasagni–is transformed into Rakta dhatu (formed blood cells), the second fundamental bodily tissue. Rakta dhatu in turn, with the help of raktagni, becomes mamsa dhatu (muscle), and so on.
Since the dhatus support and derive energy from each other; affecting one can influence others. For instance, interference in the manufacture of the plasma affects the quality of the blood, which in turn effects the muscle.