Three reasons you should not do Shoulderstand

Shoulderstand – (Sarvangasana)
“Healthy thyroid means healthy functioning of all the organs of the body”
The Shoulderstand is called the Queen of all asanas as it benefits the whole body. It is a forward-bending posture engaging all parts of the body and stretching the shoulders, neck and upper back. In the Shoulderstand the whole body is supported by the hands, arms and shoulders. As the body is inverted the blood flows to the heart without any strain by force of the gravity.
The Shoulderstand nourishes the thyroid gland which: regulates the body’s metabolism, controls the heart rate, promotes the growth and balances the digestive and nervous system. This asana tones the legs and abdomen increasing circulation to those areas. It massages the abdominal organs and it relieves stress. Because of the enriched blood flow to the brain it also relieves emotional and mental stress, headaches and it is very tranquilising.
Three important reasons you should not do Shoulderstand:
1) If you have High Blood Pressure the posture is better to avoid.
2) Anyone who has Cervical Spondylities should not attempt to practice this pose because as you hold the pose the weight of the body is taken through the neck.
3) If you have Glaucoma or Detached Retina please, avoid the Shoulderstand as it could worsen the condition.
When you are in the Shoulderstand there will be a sensation of extra pressure and tension in the neck because of the severe flexion in the neck. Your eyes, ears and face may also experience an increased sensation of pressure.
During the Shoulderstand the expansion of the chest is restricted leading to breathe at the rates of not less than eight breaths per minutes, and in many cases up to twenty breaths per minute.
During holding this posture the blood pressure in the brain will be an average of 110mmHg.
Issued in the interest of people practicing Hatha Yoga by Subodh Gupta, Yoga Expert based in London.