Sukhra dhatu (semen/ova), Majja dhatu (bone marrow), Asthi dhatu, Mamsa dhatu(muscle), Rakta dhatu (blood), Rasa dhatu (plasma),

Dhatus

Though the English translation of the Sanskrit word dhatu as body tissue does not convey all its subtleties of meaning, it is here used in that sense. The dhatu or body tissues are formed from and nourished by the ahaara rasa (essence of food)

There are seven kinds of dhatus; rasa (plasma), rakta ( blood), mamsa ( muscle), meda ( fat), asthi ( bone), majja ( bone marrow ) and sukla ( semen), according to sushruta, “ from rasa, blood is produced and flesh is produced from blood and further from flesh comes fat, out of which bones are produced and from them bone marrow and finally semen is generated.”

The seven dhatus

Rasa dhatu ( plasma )

Rasa dhatu the first in the sequence of the seven dhatus is formed by the action of the digestive fire on the ahaara rasa, its dominant element is water and with the help of the mobility it gets from the vata, it circulates within all the cells of the body, the function of rasa is to strengthen rakta and help nourish the entire body.

Rakta dhatu (blood)

As mentioned earlier, each dhatu is a metabolic refinement of the previous dhatu. As such the action of the ranjaka pitta on the finest essence of the rasa dhatu forms the rakta dhatu (blood). The characteristic red colouration of the blood is due to the presence of this pitta in the rakta dhatu. The chief functions of this dhatu, whose dominant element is agni (fire), are the nourishment of the body and preservation of life. Like rasa dhatu, rakta, dhatu too circulates all over the body.

Mamsa dhatu ( muscle )

Mamsa dhatu, which covers the bones and gives strength to the body, is formed from each of the rasas and the rakta dhatu. It is more solid in structure than both the rasa and the rakta dhatu.

Meda dhatu ( fatty tissue )

The finer parts of the mamsa dhatu transforms into medas ( fatty tissue ) by the influence of vata and agni, jala ( water) and prithvi (earth) are its dominant elements. The presence of the prithvi element gives it a somewhat solid structure.

Asthi dhatu ( none)

The finer essence of the meda dhatu is converted in to the most solid form of the dhatus – the asthi or bone. Prithvi and vayu ( air ) are its main components. The porous nature of bones is due to the presence of vayu.

Majja dhatu ( bone – marrow )

The finer essence of the asthi dhatu which is a semi solid substance forms into majja in the process of metabolism. The basic element in the majja dhatu is jala (water) and as such it contributes flexibility and smoothness to the body.

Sukhra dhatu ( semen / ova )

Sukhra, the seventh and the last of the products is produced from the most refined essence of the majja dhatu. The presence of this dhatu, whose basic elements is jala is the cause of ojas. Ojas which may be called the essence of all the seven dhatus, is responsible for vitality and energy.