Asthi means bone. The asthi dhatu gives solid structure to the body. In the physical body, asthi dhatu is formed as posaka (unstable) medas dhatu flows into the purisha dhara kala and is digested by the asthiagni. In addition to the formation of the bones of the body, teeth are formed through this process and are thus the upadhatu (secondary tissue) of the production of asthi dhatu. The waste products (malas) of this metabolic process are the hair and nails.
The purisha dhara kala is the membrane that holds the asthi agni. Purisha means “feces”. The term is also used to describe the large intestine as in the purishavaha srota. Here lies an important clue of the relationship between health of the large intestine and that of the bones. The large intestine is the home site of vata dosha. The close relationship between these two tissues reveals the susceptibility of the bones to vata disorders. When there is pathology in the large intestine (gas, constipation), the pathology is transferred to the bones which become more porous and air filled. Such is the case of osteoporosis.
Bones are made up of a solid structure organized as a matrix. This matrix can be visualized as the letter X. The lines that form the letter are solid and made of earth. The space between the lines is filled with air. Thus, bones create a solid but light structure, allowing the body to easily move. Long bones have a hollow core that is filled with hematopoietic tissue called the marrow. This is an aspect of the majja dhatu.
When the asthi agni is low, asthi dhatu is produced in excess. When this occurs, the tissue produced is denser. Those with a kapha nature, having lower agni, produce thicker and denser bones. Those with a pitta nature, having higher agni, produce bones that are not as dense, but are more metabolically active. This can lead to narrowing and weakness in the bones, as well as inflammation if pitta becomes vitiated. Those with a vata nature, having a variable agni, produce less asthi dhatu, and that which is produced is of poorer quality. It is thinner and more fragile.
In order to produce healthy asthi dhatu, adequate earth and air must be consumed in the proper balance through the diet. Earth is present in sweet foods such as grains and nuts and astringent foods such as beans. Air is present in bitter and pungent foods such as most vegetables. Consumption alone does not guarantee that healthy asthi will be formed. The two elements must be properly digested so that their qualities can be used to build bones. Thus jatharagni (main digestive fire) must be healthy. If it is not healthy, rather than forming healthy bones these same foods will produce ama and toxify the body and mind.
Bone pathologies can be simple or complex. Vata vitiation leads to weak or fragile bones that become osteoporotic and fracture easily. Pitta vitiation leads to bone infections (osteomyelitis) and inflammation. Kapha vitiation leads to excessively thick, dense bones. Other diseases of the bones are more complicated. Osteoarthritis is a combined vata-kapha condition in which vata (age, motion and stress) is responsible for provoking growth in an irregular fashion leading to bone spurs. Rheumatoid arthritis is a sannipatika condition whereby vata pushes kapha to cause irregular bone growth. Vata fans the flames of pitta causing inflammation and bone destruction. Ama is also present. Osteoblastic bone cancer is a sannipatika condition whereby vata simultaneously pushes kapha (bone growth) and fans the flames of agni within the affected tissue, creating a high metabolic state for growth. Osteoclastic bone cancer has a dual dosha pathology whereby vata combines with pitta resulting in a high metabolic state that destroys bone tissue.
Asthi dhatu is more than the structural tissues of the body. On a psychological level, it is what allows people to stand up for themselves within the world. One’s stature is not a function of size but quality. When the asthi dhatu is weak, so is one’s ability to stand solid in the face of adversity or controversy. This should not be mistaken as courage. It is steadfastness. It is the ability to be unwavering in one’s convictions. When the asthi dhatu is healthy, there is a healthy confidence in one’s ideas, decisions, and beliefs. As the asthi dhatu increases and becomes excessive, the qualities of the earth element increase and a person becomes overly attached, obstructive, and stubborn. It becomes difficult to move or shift directions. When the asthi dhatu is deficient, the qualities of the earth element decrease and there is little attachment, causing a person to shrink to the background, flowing with the will of others. Kapha dosha is responsible for excesses in asthi dhatu. Vata dosha is responsible for deficiencies. Short term pitta imbalances do not greatly affect the psychological aspect of the asthi dhatu. However, long term vitiation burns out the dhatu resulting in deficiency.
In the subtle body, the health of the asthi dhatu is dependent upon the flow through the muladhara chakra. Prana flowing through this chakra carries the qualities of the earth element throughout the subtle body and creates a solid sense of self. The flow of prana through anahata and vishuddha chakras is also important. Through these chakras, the qualities of air and ether are circulated respectively. As the flow of prana increases through these chakras, so too do their respective elemental qualities and this results in a weakening of the asthi dhatu both physically and psychologically.
As you cannot assess the health of the asthi dhatu directly except through medical testing, it is necessary to assess the asthi dhatu via the upadhatus and malas of its production. Thus, by examining the hair, nails, and teeth the practitioner can infer the state of the asthi dhatu.
When the asthi dhatu is deficient, hair density becomes scant. Hair loss may be distributed throughout the scalp or in patches. In addition, palpation of the nails reveals that they have become thin and break easily. The teeth will appear crooked or become darker (gray) than usual. These findings are consistent with deficiency due to vata vitiation.
When the asthi dhatu is in excess, hair density becomes full. In addition, the nails are thick and the teeth are large, straight, and white. These are the signs of kapha vitiation within the asthi dhatu. However, these findings are more difficult to discern than deficiency, because a person with a kapha prakruti will also exhibit these same findings. Thus, secondary signs of kapha vitiation should also be observed, especially those within the digestive system, such as sluggish digestion and the mind such as stubbornness. When these findings are present in addition to dense hair, thick nails, and white teeth it can be assumed that kapha has entered the asthi dhatu.
When pitta has entered the asthi dhatu, the teeth and nails will become a pale shade of yellow and the hair will lose its color and turn gray. Over time, the nails will become weaker and the hair may fall out as deficiency sets in due to burn out.
Healing the asthi dhatu means restoring the proper quantity and quality of earth and air in the body and normalizing the flow of these qualities through the chakras. The proper quantity varies with the constitution of the individual. Those with more kapha in their constitution will naturally have strong asthi dhatu. This makes depletion less likely and excess more likely. Those with more of a vata constitution tend to have a naturally lower amount of asthi dhatu and are the most susceptible to depletion. Those with a pitta nature tend to have a moderate quantity of asthi dhatu, and are prone to depletion only when exposed to excessive heat for an extended period or when affected by a vata imbalance.
When vata dosha has entered the asthi dhatu, the best treatment is to increase the quantity of earth element in the diet. Earth is found in the largest amount in sweet tasting foods such as grains, meats, nuts, and bones and to a lesser degree in root vegetables. It is not found to any significant degree in fruits or leafy green vegetables. Thus, these should be deemphasized in the diet.
When kapha dosha has entered the asthi dhatu, the best treatment is to decrease the quantity of earth element and increase the quality of the air element. Foods that are high in air include most fruits and leafy green vegetables. Note that excessive fruit may aggravate the watery aspect of kapha and so caution should be taken. The pungent and bitter tastes are best for increasing the qualities of air in the body. Thus, increasing the use of spices is important. In general, the diet should be light.
When pitta has entered the asthi dhatu, it is important to decrease the quality of the fire element. Thus, the diet should be cool and deemphasize hot spices and cooked oils. Cooling foods that also nourish asthi dhatu such as whole milk, wheat, and other grains should be taken. Beans may be taken if they are digested well and gas does not form.
Exercise increases the asthi agni supporting the formation of high quality boney tissue. Care should be taken when exercising however as weakness in the asthi dhatu makes the bones more likely to fracture. Thus, when significant weakness is present, the patient should begin with mild weight bearing exercises. Walking is a healthy place for most patients to begin. However, in the most severe situations as often occurs in the elderly, it may be best to begin with a reduced weight bearing exercise such as water aerobics. As time goes on exercise can become more weight bearing and may be practiced for longer periods of time. Weight bearing exercises are particularly beneficial for the spinal column, hips and legs but do not benefit the wrists and shoulder. Additional exercises that place stress on these joints are also important. A properly designed yoga practice can place appropriate stress on each of the joints of the body strengthening the asthi dhatu while providing the additional benefits of deep relaxation and mindfulness.
Meditation for spiritual realization increases the qualities of the ether element in the body and mind. Thus, meditation for healing the asthi dhatu must be modified. Meditation while sitting on the floor creates a closer connection with the earth and is better than in a chair. Attention on the muladhara chakra and its connection to the earth also supports building the qualities of the earth element. Visualization of earth energy entering from the base of the spine during meditation and being circulated by the muladhara chakra creates a greater sense of feeling grounded and steady. This supports asthi dhatu. The mantra of the Muladhara chakra is lam. Quietly chanting lam with attention on muladhara chakra enhances the qualities of earth in the body and mind.
Meditations that increase ether and air are beneficial when asthi dhatu is in excess and the earth element is too strong. Air fills the space created by ether, and this purifies the asthi dhatu. Meditations on the anahata chakra and vishuddha chakras and chanting their respective bija mantras; yum and hum increase the qualities of air and ether respectively.
Several herbs are beneficial for treating bone weakness (osteoporosis) and support healing due to fractures. These conditions are most commonly due to vata dosha vitiation. For these conditions comfrey, oatstraw and amalaki are all excellent. Comfrey has long been used for supporting the healing of bones following fracture. It is cooling and moist and balances vata and pitta doshas. Oatstraw is a cool tonic that also balances vata and pitta and has been shown to stimulate bone growth. Amalaki, an outstanding general tonic for the body, is also traditionally used to support bone development. Bhringaraj is an important herb that can be used for both tonification of the bones and purification. It is most beneficial for pitta dosha. Guggul and kutki are two herbs that are specific for purification of the bones and best for treating kapha dosha in the asthi dhatu.
In summary, a healthy asthi dhatu leads to strong bones capable of carrying us though our lifetime. They allow for motion when movement is necessary, and steadiness in the face of adversity. In order to keep the dhatu healthy, it is important to know one’s prakruti and vikruti and then to take the appropriate actions to restore balance.