Your lungs are your seat of power, and smoking damages your lungs, so it damages your seat of power.
The lungs are half of your metal meridian pair, paired with the colon. If they are damaged your metal meridians will be out of balance. If your metal meridians go out of balance with each other too much, they will affect the other meridians and organs.
Physically, your lungs have a definite connection to your heart. If you have unhealthy lungs, your heart will have to work harder and will become stressed. You may even have a heart attack.
In addition to things like this are the reasons posted above for not smoking, although I actually think that you don’t necessarily bring bad qi in, but rather, unhealthy lungs coated with tar prevent you from taking in as much good qi. In the end it doesn’t really matter, though, as you will still be taking in more bad than good.
Postures from the Taiji form, Fishes in Eight and Grasp the Sparrow’s Tail, heal the lungs and colon. The Triple Heater exercise and Wave Hands Like Clouds help to balance the energy out.
I worked for almost a year with vaporized chemicals that seriously damaged my lungs, and I found that my endurance and power suffered. In addition to these things, I have personally found that I now become seriously ill with lung infections one to two days after smoking (marijuana, though), so I had to give it up. While in western medical terms that might be a damaged immune system or something like that, I think in TCM terms it is weakened Wei Qi, the aura that protects us from outside attacks like illnesses.
If smoking in fact damages the Wei Qi, then it will also affect Iron Body adversely as the Wei Qi is the Qi we build up in this practice.
The lungs are also the controller of the skin and hair. The skin is the backup organ for the liver.
In addition to this, smoking is a bad habit. Dmagae to the colon meridian means the individual wil have a hard time changing and abandoning bad habits (like smoking). It also means that the person will hang onto bad thoughts and will affect mental health. The mind and spirit are in the heart. If the heart becomes damaged, mental clarity, memory, thinking, and sleep will become affected.
The small intestine is connected energetically to the heart. The small intestine separates pure from impure. So if we smoke and take in bad qi while hampering the intake of good qi, and refuse to get rid of it or change the habit, the small intestine if damaged cannot separate the pure from impure and so we store the good and bad qi together. If the small intestine is also affected, we also cannot distinguish between useful and useless thought.
(I personally know smokers of all types whose thought processes are clouded with useless thought. It is nearly impossible to have a meaningful conversation with two of them because of this.)
The small intestine is physically connected with the stomach. The stomach is part of the earth meridian, along with the spleen, and is what keeps us grounded. Things like not being able to hold a conversation with someone are an indication of damage to this meridian. Damage to the stomach meridian can also lead to stomach disorders. Damage to the spleen can lead to things like weak muscles and a constant desire for a nap. If the spleen is weakened, it will not properly distribute qi taken from food, and will in fact cause a loss of appetite. So then not only will it not dostribute qi, we take in less and less.
Just follow the rest of the energetic and physical connections. You’ll see that smoking seriously messes you up.
“I put forth my power and he was broken.
I withdrew my power and he was ground into fine dust.”
-Aleister Crowley, The Vision and the Voice