What is Yin Deficiency

What is Yin? 

Yin is the opposite and yet complimentary partner Yang. The theory of Yin Yang is a very important concept in Chinese medicine. When we look at the classic Yin Yang or Tai Ji symbol, it depicts a balance between Black and White. Yin, represented by black, includes the characteristics of night, shadows, anything damp or wet, it is dense and cold. Yang represented by white, includes the characteristics of sunlight, daytime, warmth, dryness, energetic substances. It is at one understanding very simple yet at another interpretation, one of the most complex academic theories in Chinese medicine. Yin and yang are complementary and cannot exist without each other. They are constantly changing into each other.

Generally speaking, in our bodies, Yin is the deepest aspect of our body. Yin is considered the foundation of blood or deeper body substance that creates blood. All of the organs are separated into Yin and Yang organs. Our Yin organs are the more dense, solid organs, such as the liver, kidneys, heart, lungs, spleen. The Yang organs are considered hollow; such as the small intestine, large intestine, bladder, and gallbladder. Yin is influenced by time of day, with twilight and night time being considered a Yin time. Sleep is a yin activity.

When the Yin of your body is healthy, your energy cycles are in perfect balance throughout the day. Your sleep is peaceful, for approximately eight hours a night. You will have adequate energy to complete your work. The Yin, like your blood, will help anchor your emotions, and it will be easy to manage stressful environments, demanding jobs, etc without feeling triggered into a stress response.

Signs and Symptoms of Yin Deficiency

  • Spontaneous afternoon sweats
  • Night sweats
  • Hot flashes (Flushes)–especially in the afternoon and evening
  • Five palm Heat— meaning the palms of your hands, soles of your feet, or all of the above will feel hot periodically throughout the day. You may feel yourself having to kick your feet out from under the blankets throughout the night when this happens.
  • Difficulty staying asleep or frequent waking throughout the night
  • Dry hair, dry skin, dry mucus membranes
  • Fatigue — deeper than the blood deficiency fatigue
  • Frequent urination during the day
  • Frequent nocturnal urination

What causes Yin Deficiency? 

Yin deficiency can occur for a wide variety of reasons. Living in a dry climate can slowly deplete Yin. Excessive sweating and exercise, stress, living in an extremely noisy environment, long periods of worry, and overconsumption of hot spices, caffeine, alcohol, cigarettes, other drugs, and refined foods, will also drain Yin.

Most chronic illnesses, autoimmune disorders, and wasting diseases will either start out with a Yin deficiency clinical picture or will develop Yin deficiency in conjunction with other symptoms. These cases are inherently more complicated and need supervision of a trained health care provider.


This factsheet is not intended to diagnose or assess. The information provided is not to be considered a substitute for consultation with a qualified health care practitioner.

James O’Sullivan from Galway is a credible and engaging speaker, a people friendly practitioner and lecturer of Integrated Medicine, serving his patients, his students and the public with the positive benefits of both Conventional Western Medicine and Traditional Chinese Medicine. He is a respected author and has appeared on many public media. #jamushur