Shukra Dhatu (शुक्र धातुः)
Shukra Dhatu (Samskrit: शुक्र धातुः) is one of the 7 body tissues as per Ayurveda. It is the 7th dhatu in Sharira (शरीरम्) according to Ayurveda. Since it is developed last i.e. at the end of dhatu (धातुः) development and nourishment pathway, it is called as 7th or the last dhatu. Shukra literally means semen, sperm, clear, lucid, white or spotless. Since Shukra dhatu passes through rigorous metabolic transformations occurring at every stage during development of all 7 dhatus and develops at the end of this pathway, it is more clear or spotless. Thus it is also called as purest dhatu from which ojas (ओजः) also develops.
व्युत्पत्तिः ॥ Etymology
The term shukra (शुक्रम्) originates from the root word "शुच क्लेदे + “ऋज्रे न्द्राग्रवज्रेति ।”
In Ayurveda literature, 2 dimensions of shukra dhatu are be found to be mentioned. One form of it is Shukra dhatu which is ejaculated at the end of mating and is responsible for conception. The other form of shukra dhatu refers to the body tissue that is present in every part of shariram (शरीरम् physical body) and controls the rebuilding of body tissues, new cell/tissue generation and overall development. Thus the dhatu which controls the function of reproduction of any form in the body is called as shukra dhatu.
शुक्रधातोः स्थानम् ॥Location of Shukra Dhatu
Shukra dhatu is present all over the body as stated by Acharya Charaka.
सर्वदेहगतं शुक्रं प्रवदन्ति मनीषिणः| (Char. Samh. 15.26)
sarvadehagataṁ śukraṁ pravadanti manīṣiṇaḥ| (Char. Samh. 15.26)
In spite of that, there are some body parts which are specifically mentioned to be the related to Shukra dhatu. Those are Vrishana (वृषणः | testicles), Medhra (मेढ्रः | Penis), Stana (स्तनौ | Breasts). Also, vessels carrying shukra dhatu have also been mentioned to be associated with transportation of shukra.
शुक्रधातोः उत्पत्तिः ॥ Formation of shukra dhatu
Shukra dhatu is formed from 'Majja dhatu'(मज्जा धातु). When Majja dhatu is subjected to the process of micro-transformation (सूक्ष्मपचनम्), one processed part of it is specifically utilized to provide nourishment to the next dhatu in order i.e. Shukra Dhatu (शुक्र धातु). This part is responsible for development and nourishment of Shukra dhatu in body. Transformation of unctuous part of predecessor majja (मज्जा) into Shukra happens through a specific process. It is stated that, the asthi dhatu (अस्थि धातुः) develops porosity due to action of vayu (वायुः) and akasha (आकाशम्) mahabhutas (महाभूतानि). The unctuous part of majja dhatu present inside this porous asthi dhatu oozes out of these pores and reaches all parts of the body through channels of transportation of shukra dhatu (शुक्रवह स्रोतसम् | shukravahasrotas). This unctuous part is known as shukra. After puberty, at the time of sexual excitation or urge of ejaculation (वेगः | vega), the shukra reaches to basti from all over the body and then it is discharged through urethra. This process happens just like ghee is melted by heat.
शुक्रधातोः उपधातवः ॥ Upadhatu of Shukra dhatu
Shukra dhatu when subjected to the process of micro-transformation (सूक्ष्मपचनम्), it generates 1 entity which is known as Upadhatus (उपधातु | metabolic by-products which function as body tissues) of Shukra dhatu. As per Acharya Sharangadhara Ojas (ओजः) is the metabolic byproduct (upadhatu) of shukra. However, all acharyas do not agree to this. Some are of the opinion that since Shukra develops as essence of all dhatus there is no metabolic byproduct of it.
शुक्रधातोः मलाः ॥ Mala of Shukra dhatu
Ayurveda acharyas have opined that Shukra being the purest form of dhatu generated at the end of dhatu nourishment and development pathway, there is no metabolic byproduct or waste formed during its formation. Thus Shukra is devoid of mala (मलः).
शुद्ध शुक्र लक्षणानि ॥ Qualities of purest form of shukra
The best qualities of Shukra dhatu which is ejaculated out during the process of mating plays the key role in reproduction. Certain qualities of shukra which are helpful in reproduction are known to be best qualities of shukra. The Shukra which is unctuous (स्निग्धम् | snigdha), viscous (घम् | ghana), slimy (पिच्छिलम् | picchila) in texture, sweet (मधुरम् | madhura) in nature (soothing, cool, contains fructose) and looks like white crystal quartz (स्फटिकाभम्) is considered to be a good quality shukra.
शुक्रधातोः पाञ्चभौतिकत्वम् ॥ Panchabhoutiktwa of Shukra dhatu
Among 5 mahabhutas (पञ्चमहाभूतानि), Shukra is believed to have dominance of 4 mahabhutas viz Vayu (वायुः), Agni (अग्निः), Jalam (जलम्) and Prthvi (पृथ्विः).
शुक्रसारता लक्षणानि ॥S hukra sarata lakshanas
Those who have supreme quality of Shukra dhatu in a body are identified by some characteristic features. These features are called as Shukra-sarata features (शुक्रसारता लक्षणानि). These features are manifested on various organs and body parts which reflect beauty and external appearance of a person e.g skin, eyes, teeth. Thus one can identify the quality of Shukra dhatu by assessing presence or absence of following signs in body.
सौम्याः सौम्यप्रेक्षिणः क्षीरपूर्णलोचना इव प्रहर्षबहुलाः स्निग्धवृत्तसारसमसंहतशिखरदशनाः प्रसन्नस्निग्धवर्णस्वरा भ्राजिष्णवो महास्फिचश्च शुक्रसाराः|
ते स्त्रीप्रियोपभोगा बलवन्तः सुखैश्वर्यारोग्यवित्तसम्मानापत्यभाजश्च भवन्ति|| (Char. Samh 8.109) 
saumyāḥ saumyaprekṣiṇaḥ kṣīrapūrṇalocanā iva praharṣabahulāḥ snigdhavr̥ttasārasamasaṁhataśikharadaśanāḥ prasannasnigdhavarṇasvarā bhrājiṣṇavo mahāsphicaśca śukrasārāḥ|
te strīpriyopabhogā balavantaḥ sukhaiśvaryārogyavittasammānāpatyabhājaśca bhavanti|| (Char. Samh 8.109)
Meaning: The persons endowed with the essence of shukra dhatu are gentle (saumya), having charming yet decent appearance (saumyaprekshina), beautiful eyes as if filled with milk (kshirapurnalochana) and immensely exhilarated (praharshabahula). Their teeth are unctuous, rounded, firm, even and compact. They have prominent buttocks (large pelvic girdle). They have pleasant, unctuous complexion and voice. They are brilliant. They are liked by women for enjoyment, are strong and endowed with happiness, leisure, health, wealth, honor, and progeny.
शुक्रधातुकार्यम् ॥ Function of shukra dhatu
Reproduction is the prime function of Shukra dhatu.  In Ayurveda this function is called as Garbhotpadanam (गर्भोत्पादनम्, Garbha (गर्भः)- Embryo; Utpadanam (उत्पादनम्)-generation). Thus, irrespective of the gender, Shukra dhatu present in the body is responsible for the function of reproduction. Apart from that, it also impacts the various psycho-somatic attributes like courage, lust, strength, pleasure, love and affection. It is closely related with human emotions and manas (मनस् mind).
शुक्रदुष्टिहेतवः ॥ Causes of vitiation
Shukra dhatu can get vitiated by various dietary and lifestyle factors. Acharya Charaka has listed such factors under the causes vitiating Shukravaha srotas (शुक्रवह स्रोतसम्) i.e. channels for transport and transformation of shukra dhatu. The causes are listed below,
आहार हेतवः ॥ Dietary causes
- Consumption of incompatible food
- Excessive consumption of dry, bitter, astringent, salty, sour and hot (energy or heat generating) food.
मानसहेतवः ॥Emotional and psychological causes
- Excess stress
- lack of relaxation, confidence, intimacy/familiarity
विहारहेतवः ॥ Lifestyle causes
- Excess indulgence in intercourse
- Untimely coitus, coitus other than in vagina, or
- complete abstinence from intercourse for long time(suppression of discharge of semen),
- Excess exercise, senility,
- improper usage of surgical instruments, alkali (क्षाराः kshara), heat or cautery (अग्निः agni),
- emaciation due to other diseases,
- repression of natural urges,
- injury, morbidity causing vitiation of dhatus, doshas individually or collectively reaching reproductive system
All these causes lead to vitiation of shukra as well as the channels that transport and transform Shukra dhatu.
शुक्रधातोः स्वस्थ्यरक्षणे प्राधान्यम् ॥Importance of Shukra dhatu in preservation of health and wellness
Shukra dhatu being the essence of all 7 dhatus has significant role in maintaining the overall strength of the individual. Vigour and vitality are the other 2 aspects closely related with the quality of Shukra in one's body. Moreover, Shukra plays the key role in the reproduction. Therefore in order to produce lineage of progeny, Shukra is the integral dhatu. The quality, health and wellbeing of the progeny depends upon the qualities of Shukra from which it is developed. Therefore health and wellbeing of not just that person but also his lineage rely largely on the Shukra dhatu of the individual. Vajikarana (वाजीकरणम्) therapies described as one of the 8 branches of Ayurveda deals with methods and ways to produce and maintain good quality of Shukra in one's body which provides basis for healthy progeny.
- Charaka Samhita (Chikitsasthanam Adhyaya 15 Sutram 26)
- Charaka Samhita (Vimanasthanam Adhyaya 5 Sutram 8)
- Sushruta Samhita (Sharirasthanam Adhyaya 9 Sutram 12)
- Charaka Samhita (Chikitsasthanam Adhyaya 15 Sutram 33-35)
- Sharangadhara Samhita (Purvakhanda Adhyaya 5)
- Charaka Samhita (Chikitsasthanam Adhyaya 30 Sutram 40)
- Charaka Samhita (Sharirasthanam Adhyaya 2 Sutram 4)
- Charaka Samhita (Vimanasthanam Adhyaya 8 Sutra 109)
- Available from Charakasamhitaonline.com
- Ashtanga Hrudayam (Sutrasthanam Adhyaya 11 Sutra 4)
- Sushruta Samhita (Sutrasthanam Adhyaya 15 Sutram 5)
- Charaka Samhita (Vimanasthanam Adhyaya 5 Sutram 19)
- Charaka Samhita (Chikitsasthanam Adhyaya 30 Sutram 135-139)