Long before medical science ever knew about the existence of thyroid glands, yogis had devised practices, which not only maintained healthy glands and metabolism, but also were part of a system of enlightenment.
Sarvangasna (shoulder stand) is the most suitable and effective asana for the thyroid gland. An enormous pressure is placed on the gland by this powerful posture. As the thyroid has one of the largest blood supplies of any body organ, this pressure has dramatic effects on its function, improving circulation and squeezing out stagnant secretions. After sarvangasana, we should perform matsyasana, and from sarvangasana we can practice halasana. All these practices positively result in better health of the thyroid gland. At the same time, all these practices should be avoided in severe thyroitoxicosis, physical debility or a goitre that is enlarged very much, where medical therapy is obviously the first line of treatment to be given. However, adding iodine once again to the diet is the first obvious step.
Other effective asanas include Surya Namskara, Pavamuktasana with emphasis on the head and neck exercises, yoga mudra, Suptavajrasana and all backward bending asanas.
Pranayama for Thyroid diseases:
The most effective Pranayama for thyroid problems is Ujjayi. It acts on the throat area and its relaxing and stimulating effects are most probably due to stimulation of ancient reflex pathways within the throat area, which are controlled by the brainstem and hypothalamus. This practice also gives us direct access into the pranic and psychic net work, the substructure of metabolic activity. Nadi shodhana pranayama is useful in re-balancing metabolism.